CN106104778A - Goods and method for polymer surfaces and the controlled bonding of carrier - Google Patents

Abstract

A substrate having a polymer bonding surface having a first surface energy, a carrier and a plasma polymerized surface modification layer, the polymer bonding surface having a second surface energy, the plasma A polymeric surface modification layer releasably bonds the polymeric bonding surface to the glass bonding surface. A plasma polymerized layer can be formed prior to bonding to reduce the surface energy of the glass bonding surfaces. And after undergoing vacuum annealing for 1 hour in an environment at a temperature of 120° C., the substrate can be debonded from the carrier without damage.

Description

Articles and methods for controlled bonding of polymeric surfaces to supports

Background technique

This application claims priority to US Provisional Application Serial No. 61/931924, filed January 27, 2014, which application is based upon and is hereby incorporated by reference in its entirety.

field of invention

The present invention relates to methods and articles for processing flexible sheets on supports, and more particularly to methods and articles for processing flexible glass sheets on glass supports.

technical background

Flexible substrates offer the possibility of cheaper devices employing roll-to-roll processing, as well as the potential for thinner, lighter, more flexible and durable displays. However, the technologies, equipment and processes required for roll-to-roll processing of high-quality displays have not been fully established. As panel makers have invested heavily in tool kits for processing large sheets of glass, laminating flexible substrates to carriers and fabricating display devices via sheet-to-sheet processing offers the opportunity to develop thinner, lighter, and more flexible displays. A shorter-term solution for a worthwhile program. Displays on polymer sheets such as polyethylene naphthalate (PEN) have been demonstrated, where device fabrication is a sheet-sheet format of PEN laminated to a glass carrier. The upper temperature limit of PEN limits the device quality and the processes that can be used. Furthermore, the high permeability of polymer substrates leads to environmental degradation of OLED devices, requiring near-hermetic encapsulation. Thin-film encapsulation offers the possibility to overcome this limitation, but has not been proven to provide acceptable yields at large volumes.

In a similar manner, display devices can be fabricated using glass carriers laminated to one or more thin glass substrates. The low permeability, improved temperature and chemical resistance of thin glass are expected to enable higher performance, longer life flexible displays.

However, heat, vacuum, solvents and acids, and ultrasound, flat panel display (FPD) processing require a strong bond of thin glass to the carrier. FPD processing typically involves: vacuum deposition (sputtering of metals, transparent conductor oxides, and oxide semiconductors, chemical vapor deposition (CVD) of amorphous silicon, silicon nitride, and silicon dioxide, and dry etching of metals and insulators), thermal Processing (including CVD deposition around 300-400°C, p-Si crystallization up to 600°C, oxide semiconductor annealing up to 350-450°C, dopant annealing up to 650°C, and contact annealing), acid etching (metal etching, oxide semiconductor etching), solvent exposure (stripping photoresist, deposition of polymer encapsulation), and ultrasonic exposure (solvent stripping of photoresist Neutralizes in aqueous cleaning, usually alkaline solutions).

Adhesive wafer bonding is widely used in micromechanical systems (MEMS) and semiconductor processing for less demanding back-end steps of processing. Commercial adhesives from Brewer Science and Henkel are typically thick polymeric adhesive layers, 5-200 microns thick. The large thickness of these layers creates the possibility of contaminating the FPD processing with large amounts of volatile species, entrapped solvents, and adsorbed species. These materials thermally decompose and outgas above about 250°C. By acting as a sink for gases, solvents, and acids, the material can also cause contamination of downstream steps, which can outgas in subsequent processes.

U.S. Provisional Application Serial No. 61/596,727, entitled "Processing Flexible Glass with a Carrier," filed February 8, 2012 (hereinafter US'727), explains such concepts, It involves initially bonding a thin sheet (e.g., a flexible glass sheet) to a support by van der Waals forces, then increasing the bond strength in certain areas while remaining removed after processing of the sheet/support to form a device thereon (e.g., Capabilities of electronic or display devices, components of electronic or display devices, organic light emitting device (OLED) materials, photovoltaic (PV) structures, or thin film transistors). At least a portion of the thin glass is bonded to the carrier, thereby preventing device process fluids from entering between the sheet and the carrier, thereby reducing the possibility of contaminating downstream processes, that is, the bonded seal between the sheet and the carrier is hermetically sealed and in some preferred embodiments, the seal surrounds the exterior of the article, thereby preventing liquid or gas from entering or leaving any area of the sealed article.

US'727 also discloses that in low temperature polysilicon (LTPS) (low temperature is compared to solid phase crystallization processes which can be as high as about 750°C) device fabrication processes, temperatures approaching 600°C or greater, vacuum and wet etch can be used environment. These conditions limit the materials that can be used and place high demands on the support/flake. Therefore, there is a need for a carrier method that enables the processing of thin glass (thickness ≤ 0.3 mm glass) using the manufacturer's existing investment equipment without contamination or loss of the thin glass-carrier interface at higher processing temperatures. bond strength, and the thin glass is easy to debond from the carrier at the end of processing.

One of the commercial advantages of the method disclosed in US'727 is that, as shown in US'727, manufacturers will be able to use their existing capital investment in processing equipment while obtaining Benefits of Thin Glass Sheets for Thin Film Transistor (TFT) Electronics. In addition, the method enables processing flexibility, including: cleaning and surface preparation of the thin glass sheet and carrier to promote bonding; bond strengthening at bonded regions between the sheet and carrier; maintaining non-bonded (or bonded) detachability of the sheet to the carrier in areas of reduced/low strength bonding; and cutting of the sheet to facilitate release from the carrier.

During the glass-to-glass bonding process, the glass surface is cleaned to remove all metallic, organic, and particulate residues, leaving a predominantly silanol-terminated surface. The glass surfaces are first brought into intimate contact, where van der Waals and/or hydrogen bonding forces push them together. Using heat and optionally pressure, the surface silanol groups condense to form strong covalent Si-O-Si bonds across the interface, permanently fusing the glass pieces. Metallic, organic and particulate residues prevent bonding by masking the surface and preventing the intimate contact required for bonding. High silanol surface concentrations are also required to form strong bonds, since the number of bonds per unit area depends on the probability of two silanol species on opposing surfaces reacting to allow water to condense. Zhuravlel has reported an average number of hydroxyl groups per nm of ^4.6-4.9 for well-hydrated silica. Zhuravlel, LT, "The Surface Chemistry of Amorphous Silika, Zhuravlev Model", Colloids and Surfaces A: Physiochemical Engineering Aspects (Colloids and Surfaces A: Physiochemical Engineering Aspects), 173( 2000) 1-38. In US '727, non-bonded regions are formed within the bonded perimeter, and the main way of forming such non-bonded regions is described as increasing surface roughness. An average surface roughness greater than 2 nm Ra can prevent the formation of glass-to-glass bonds during the temperature rise of the bonding process. In U.S. Provisional Patent Application Serial No. 61/736,880, entitled "Facilitated Processing for Controlling Bonding Between Sheet and Carrier," filed December 13, 2012 by the same inventor No. (hereinafter referred to as US'880), by controlling van der Waals and/or hydrogen bonding between the support and the thin glass sheet, controlled bond regions are formed, but covalently bonded regions are still used. Thus, while the articles and methods for processing sheets and carriers in US'727 and US'880 are capable of withstanding the harsh environment of FPD processing, they are undesirable for certain applications due to thin Strong covalent bonding between glass and glass support as a covalent form (for example, Si-O-Si, the adhesion of the bond is about 1000-2000mJ/m ² , which is about the breaking strength of glass) hinders the regeneration of the support. use. Prying or peeling cannot be used to detach the covalently bonded portion of the thin glass from the carrier, thereby removing the intact flakes from the carrier. Instead, the non-bonded areas with the device on them were scribed and extracted, leaving the bonded perimeter of the thin glass sheet on the carrier.

Contents of the invention

In view of this, there is a need for a sheet-carrier article that can withstand the rigors of FPD processing, including high temperature processing (without outgassing that would be incompatible with the semiconductor or display manufacturing process for which it will be used), yet achieve The entire sheet area is removed (all at once, or in segments), so that the carrier can be reused for processing another sheet. This specification describes a way to control the adhesion between the carrier and the sheet, resulting in a temporary bond that is strong enough to pass FPD processing (including LTPS processing), but weak enough to allow debonding of the sheet from the carrier , even after high temperature processing. Such controlled bonding can be used to create articles with reusable supports, or patterned regions with controlled and covalently bonded areas between the support and the sheet. More specifically, provided herein are surface modification layers (including various materials and associated surface heat treatments) that can be provided on flakes and/or supports to simultaneously control room temperature van der Waals and/or hydrogen bonding between flakes and supports bonding and high temperature covalent bonding. Even more specifically, room temperature bonding can be controlled sufficiently to hold the flake and support together during vacuum processing, wet processing, and/or ultrasonic cleaning processing. At the same time, high-temperature covalent bonding can be controlled to prevent permanent bonding between flakes and support during high-temperature processing and maintain sufficient bonding to prevent delamination during high-temperature processing. In alternative embodiments, surface modification layers can be used to create various controlled bond regions (where the support and sheet remain sufficiently bonded during various processing steps, including vacuum processing, wet processing, and/or ultrasonic cleaning processing). junctions) as well as covalently bonded areas to provide further processing options, such as maintaining the seal between the carrier and the sheet, even after cutting the article into smaller pieces for additional device processing. In addition, some surface modification layers provide bond control between the support and sheet while reducing outgassing emissions under harsh conditions in FPD (eg LTPS) processing environments including, for example, high temperature and/or vacuum processing. Furthermore, in an alternative embodiment, some surface modification layer can be used on the support with glass bonding surface to allow controlled bonding with the flakes with polymeric bonding surface. The polymer bonding surface may be part of a polymer sheet on which an electronic or other structure is formed, or the polymer bonding surface may be part of a composite sheet including a glass layer on which electronics or other structures.

Additional features and advantages of the present invention are given in the following detailed description, some of which are easily understood by those skilled in the art from the description, or implemented in accordance with the text description and drawings. know. It is to be understood that both the foregoing general description and the following detailed description are examples of various aspects, and are intended to provide an overall overview or framework for understanding the nature and character of the invention as it is claimed.

The accompanying drawings are included to provide a further understanding of the principles of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate one or more embodiments of the invention, and together with the description serve to explain, for example, the principles and operations of the invention. It should be understood that the various features disclosed in this specification and drawings can be used in any and all combinations. As a non-limiting example, various features may be combined with each other as described in the appended claims.

Description of drawings

Figure 1 is a schematic side view of an article having a carrier bonded to a sheet with a surface modifying layer in between.

FIG. 2 is an exploded and partial cross-sectional view of the article of FIG. 1 .

Figure 3 is a graph of surface hydroxyl concentration on silica as a function of temperature.

Figure 4 is a graph of surface energy versus annealing temperature for SC1 cleaned glass sheets.

Figure 5 is a graph of the surface energy of a fluoropolymer film deposited onto a glass sheet versus the percentage of one of the constituent materials from which the film was made.

Figure 6 is a schematic top view of a sheet bonded to a carrier through a bonding region.

Figure 7 is a schematic side view of a stack of glass sheets.

FIG. 8 is an exploded view of one embodiment of the stack of FIG. 7 .

Figure 9 is a schematic diagram of the test setup.

Figure 10 is a general plot of surface energy (of different portions of the test setup of Figure 9) versus time for various materials under different conditions.

Figure 11 is a graph of the change in % bubble area versus temperature for various materials.

Figure 12 is another graph of the change in % bubble area versus temperature for various materials.

Figure 13 is a graph of the surface energy of fluoropolymer films deposited onto glass slides versus the percentage of a gas used during deposition.

Figure 13A is a graph of the surface energy of a fluoropolymer film deposited onto a glass slide versus the percentage of a gas used during the deposition process.

Figure 14 is a graph of surface energy versus deposition time for a surface modified layer.

Figure 15 is a graph of the thickness of the surface modification layer versus deposition time on a log-log scale.

Figure 16 is a graph of surface energy versus treatment temperature for different surface modification layers.

Figure 17 is a surface coverage diagram of a surface modification layer.

Figure 18 is a summary of the performance of organic transistors fabricated on 200 micron PEN films bonded to glass supports.

detailed description

In the following detailed description, for purposes of illustration and not limitation, exemplary embodiments illustrating specific details are given in order to provide a thorough understanding of the various principles of the invention. However, it will be apparent to those of ordinary skill in the art, having the benefit of this description, that the invention may be practiced in other embodiments than those detailed herein. Moreover, descriptions of well-known devices, methods, and materials may be omitted so as not to obscure the description of the various principles of the invention. Finally, wherever applicable, the same reference numerals designate the same elements.

Ranges can be expressed herein as from "about" one particular value, and/or to "about" another particular value. When such a range is expressed, another embodiment includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the prefix "about," it will be understood that the particular value forms another embodiment. It should also be understood that the endpoints of each range are meaningful in relation to and independent of the other endpoint.

Directional terms used herein, such as up, down, left, right, front, back, top, bottom, are only used with reference to the drawings as drawn and are not intended to denote absolute orientations.

As used herein, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a component" includes aspects having two or more such components unless the context clearly dictates otherwise.

In both US'727 and US'880 solutions are provided which enable the processing of thin glass sheets on a carrier, wherein at least part of the thin glass sheet remains "unbonded" so that it can be removed from the carrier Devices fabricated on thin glass sheets. However, the perimeter of the thin glass is permanently (or covalently or hermetically) bonded to the carrier glass by forming a covalent Si-O-Si bond. The covalently bonded perimeter prevents carrier re-use because the thin glass in the permanently bonded area cannot be removed without damaging both the thin glass and the carrier.

To maintain favorable surface shape properties, the support is typically a display grade glass substrate. Thus, in some cases, it is wasteful and expensive to throw away the carrier after one use. Thus, in order to reduce display manufacturing costs, it is desirable to be able to reuse a carrier for processing rather than a sheet substrate. Articles and methods are provided herein that enable processing of flakes through the harsh environment of an FPD processing line, including high temperature processing (wherein high temperature processing is processed at temperatures > 400°C and may vary depending on the type of equipment being processed, Examples include temperatures as high as about 450°C in amorphous silicon or amorphous indium gallium zinc oxide (IGZO) backplane processing, as high as about 500-550°C in crystalline IGZO processing, or as high as about 600-650°C in typical LTPS processing. °C), and still be able to easily remove the flakes from the carrier without damaging the flakes or the carrier (eg, one of the carrier and the flakes breaks or crumbles into two or more pieces), so that the carrier can be reused.

As shown in Figures 1 and 2, the article 2 has a thickness 8, and it includes a carrier 10 having a thickness 18, a sheet 20 having a thickness 28 (i.e., having a thickness < 300 microns, including but not limited to thicknesses such as 10-50 microns , 50-100 microns, 100-150 microns, 150-300 microns, 300, 250, 200, 190, 180, 170, 160, 150, 140, 130, 120, 110, 100, 90, 80, 70, 60, 50, 40, 30, 20 or 10 microns), and a surface modification layer 30 having a thickness 38. Article 2 is designed so that while sheet 20 itself is < 300 microns, it allows for thicker sheets (i.e., approximately > .4 mm, e.g. .4 mm, .5 mm, .6 mm, . or 1.0 mm) to process the thin slice 20 in the device. That is, the thickness 8 (as the sum of the thicknesses 18, 28 and 38) is designed to correspond to the thickness of a thicker sheet for which it is designed to be used, for example, to arrange electronic devices on a substrate sheet. Components of the equipment are processed on the piece of equipment. For example, if the processing equipment is designed for a 700 micron sheet, and the thickness 28 of the sheet is 300 microns, the thickness 18 is selected to be 400 microns, assuming that the thickness 38 is negligible. That is, surface modification layer 30 is not shown to scale; rather, it is greatly exaggerated for illustrative purposes only. Furthermore, the surface modification layer is shown in the cross-sectional view. In fact, when a reusable carrier is provided, the surface modification layer will be uniformly arranged on the bonding surface 14 . Typically, thickness 38 will be on the nanometer scale, eg, 0.1-2.0 or up to 10 nm, and in some cases up to 100 nm. Thickness 38 may be measured by ellipsometer. Furthermore, the presence of a surface modification layer can be detected by surface chemical analysis, for example by ToF Sims mass spectrometry. Thus, the contribution of thickness 38 to article thickness 8 is negligible and may be ignored in calculations to determine the appropriate thickness 18 for processing a carrier 10 for a given sheet 20 having thickness 28 . However, to the extent that surface modifying layer 30 has any appreciable thickness 38, it may be considered to determine thickness 18 of carrier 10 for a given thickness 28 of sheet 20, and a given thickness for designing processing equipment.

Carrier 10 has first surface 12 , bonding surface 14 , perimeter 16 and thickness 18 . Furthermore, carrier 10 may be any suitable material including, for example, glass. The support does not have to be glass, instead it can be ceramic, glass-ceramic or metal (since surface energy and/or bonding can be controlled in a similar manner as described below for glass supports). If made of glass, the carrier 10 can be of any suitable composition including aluminosilicate, borosilicate, aluminoborosilicate, soda calcium silicate, and depending on its end use, can be Alkaline or non-alkaline. Thickness 18 may be about 0.2-3 mm or greater, such as 0.2, 0.3, 0.4, 0.5, 0.6, 0.65, 0.7, 1.0, 2.0, or 3 mm, or greater, and will depend on thickness 28 and thickness 38 (when as above This is a non-negligible situation). Furthermore, carrier 10 may be fabricated from a single layer (as shown), or from multiple layers bonded together, including multiple sheets of the same or different materials. In addition, the carrier may be Gen 1 size or larger, such as Gen 2, Gen 3, Gen 4, Gen 5, Gen 8 or larger (eg, sheet size from 100mm x 100mm to 3m x 3m, or larger).

Sheet 20 has first surface 22 , bonding surface 24 , perimeter 26 and thickness 28 . Perimeters 16 and 26 may be of any suitable shape, and may be the same as each other or may be different from each other. Furthermore, sheet 20 may be any suitable material including, for example, glass, ceramic, or glass-ceramic. In some cases, sheet 20 may be a polymer or composite sheet (having a polymer and/or glass bonding surface). When made of glass, flakes 20 may then be of any suitable composition, including aluminosilicates, borosilicates, aluminoborosilicates, soda calcium silicates, and depending on their end use, may be alkali-containing Or alkali-free. The coefficient of thermal expansion of the sheet can be more closely matched to that of the carrier to prevent warping of the article during processing at elevated temperatures. When processing the article 2 at lower temperatures, in which case the CTE matching is not considered, the polymer flakes can be used with the glass support. Of course, there may be instances where other polymer sheets may be used with the glass support. Thickness 28 of flakes 20 is less than or equal to 300 microns, as described above. Additionally, the slices may be Gen 1 size or larger, such as Gen 2, Gen 3, Gen 4, Gen 5, Gen 8 or larger (eg, slice sizes from 100mm x 100mm to 3m x 3m, or larger).

The article 2 not only needs to be of the correct thickness to be processed in existing equipment, it also sometimes needs to be able to withstand the harsh environment in which it is processed. For example, flat panel display (FPD) processing can include wet ultrasonic, vacuum, and in some cases high temperature (eg, > 400°C) processing. As noted above, for some processes the temperature may be >500°C, or >600°C, and as high as 650°C.

In order to be able to withstand the harsh environment in which the article 2 will be processed, such as in an FPD manufacturing process, the bonding surface 14 should be bonded to the bonding surface 24 with sufficient strength so that the sheet 20 does not contact the carrier 10. Separation occurs. And this strength should be maintained through processing, so that the sheet 20 does not separate from the carrier 10 during processing. Furthermore, in order to be able to remove the foil 20 from the carrier 10 (so that the carrier 10 can be reused), the bonding of the bonding surface 14 to the bonding surface 24 should not be too strong, in the following way: by the initially designed bonding force, and and/or through cohesive forces due to modification of the originally designed cohesive forces, which may occur, for example, when the article is subjected to processing at elevated temperatures (eg, temperatures > 400° C.). Surface modification layer 30 can be used to control the strength of the bond between bonding surface 14 and bonding surface 24 to achieve these goals simultaneously. Controlled adhesion forces are achieved by controlling the contribution of van der Waals (and/or hydrogen bonding) bonding and covalent attraction energy to the total adhesion energy by adjusting the polarity and polarity of the sheet 20 and support 10. Polar surface energy components are controlled. The controlled bond is strong enough to withstand FPD processing (including wet processing, ultrasonic processing, vacuum processing, and thermal processing (including temperatures ≥400°C, and in some cases, processing temperatures ≥500°C or ≥600°C and high to 650° C.)), and is still debondable by applying a sufficient separation force and a force that does not cause catastrophic damage to the sheet 20 and/or carrier 10 . Such debonding enables the removal of the foil 20 and the devices fabricated thereon, and also enables the reuse of the carrier 10 .

Although the surface modification layer 30 is shown as a solid layer between the flake 20 and the support 10, this is not necessarily the case. For example, layer 30 may be approximately 0.1-2 nm thick and may not completely cover bonding surface 14 everywhere. For example, coverage can be < 100%, 1-100%, 10-100%, 20-90%, or 50-90%. In other embodiments, layer 30 may be up to 10 nm thick, or even up to 100 nm thick in other embodiments. Surface modification layer 30 may be considered to be disposed between carrier 10 and sheet 20 even though it may not be in contact with one or the other of carrier 10 and sheet 20 . In any event, an important aspect of surface modification layer 30 is that it alters the ability of bonding surface 14 to bond to bonding surface 24 , thereby controlling the bond strength between carrier 10 and foil 20 . The material and thickness of the surface modification layer 30 and the treatment of the bonding surfaces 14 , 24 prior to bonding can be used to control the bond strength (adhesion energy) between the carrier 10 and the sheet 20 .

Generally speaking, according to "A theory for the estimation of surface and interfacial energies. I. derivation and application to interfacial tension (the evaluation theory of surface and interfacial energy I, the derivation and application of interfacial tension)", L.A.Girifalco and R.J.Good, J .Phys.Chem., Vol. 61, p. 904, the adhesive energy between two surfaces is as follows:

W=Y ₁ +Y ₂ -Y ₁₂ (1)

where Y ₁ , Y ₂ and Y ₁₂ are the surface energies of Surface 1 and Surface 2 and the interfacial energies of Surfaces 1 and 2, respectively. A single surface energy is usually a combination of a dispersive component γ ^d and a polar component γ ^p .

γ = γ ^d + γ ^p (2)

When bonding is primarily due to London dispersion forces (γ ^d ) and polar forces (e.g. hydrogen bonding, γ ^p ), the interfacial energy can be given by Girifalco and RJGood, supra, as follows:

${\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 12</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 2</span>}\sqrt{{{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}^{\mathrm{<span\; class="notranslate">\; d</span>}}{{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}^{\mathrm{<span\; class="notranslate">\; d</span>}}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 2</span>}\sqrt{{{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}^{\mathrm{<span\; class="notranslate">\; p</span>}}{{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}^{\mathrm{<span\; class="notranslate">\; p</span>}}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; )</span>$

After substituting (3) into (1), the adhesion energy can be approximated as follows:

$\mathrm{<span\; class="notranslate">\; W</span>}<span\; class="notranslate">\; ~</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; \&lsqb;</span>\sqrt{{{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}^{\mathrm{<span\; class="notranslate">\; d</span>}}{{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}^{\mathrm{<span\; class="notranslate">\; d</span>}}}<span\; class="notranslate">\; +</span>\sqrt{{{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}^{\mathrm{<span\; class="notranslate">\; p</span>}}{{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}^{\mathrm{<span\; class="notranslate">\; p</span>}}}<span\; class="notranslate">\; \&rsqb;</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; )</span>$

In the above formula (4), only the van der Waals (and/or hydrogen bonding) bonding component of the adhesive energy is considered. They include polar-polar interactions (Keesom forces), polar-nonpolar interactions (Debye forces), and nonpolar-nonpolar interactions (London forces). ). However, other gravitational energies may also exist, such as covalent and electrostatic bonding. Therefore, as a more general form, the above formula writes:

$\mathrm{<span\; class="notranslate">\; W</span>}<span\; class="notranslate">\; ~</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; \&lsqb;</span>\sqrt{{{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}^{\mathrm{<span\; class="notranslate">\; d</span>}}{{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}^{\mathrm{<span\; class="notranslate">\; d</span>}}}<span\; class="notranslate">\; +</span>\sqrt{{{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}^{\mathrm{<span\; class="notranslate">\; p</span>}}{{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}^{\mathrm{<span\; class="notranslate">\; p</span>}}}<span\; class="notranslate">\; \&rsqb;</span><span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; c</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; e</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 5</span>}<span\; class="notranslate">\; )</span>$

where w _c and w _e are the covalent and electrostatic binding energies. Covalent bonding energy is quite common. In silicon wafer bonding, the wafer's initial hydrogen bond pairs are heated to higher temperatures, converting many or all of the silanol-silanol hydrogen bonds into Si-O-Si covalent bonds. price key. While initial, room-temperature hydrogen bonding produces an adhesive energy of about 100-200 ^mJ /m2 (which allows separation of bonded surfaces), fully covalently bonded wafers are achieved during high-temperature (about 400-800°C) processing Pairs have a bonding energy of about 1000-3000 ^mJ /m2 (which does not allow separation of the bonded surfaces); instead, the two wafers are integrated. On the other hand, if both surfaces are perfectly coated with a low surface energy material (such as a fluoropolymer) at a thickness large enough to shield the underlying substrate from the influence, the adhesion energy will be that of the coating material, And would be very low, resulting in low or no adhesion between the bonding surfaces 14 , 24 , making it impossible to process the sheet 20 on the carrier 10 . Consider two extreme cases: (a) two Standard Clean 1 (known in the art as SC1) cleaned glass surfaces filled with silanol groups held together by hydrogen bonding at room temperature (adhesion energy about 100 -200 mJ/m ² ), then by heating to high temperature, it converts the silanols into covalent Si-O-Si bonds (adhesion energy becomes 1000-3000 mJ/m ² ). This bonding energy of the latter is too high for the pair of glass surfaces to be separated; and (b) perfectly coated ^two surfaces of fluoropolymers with low surface bonding energy (approximately 12 mJ/m2 per surface) The two glass surfaces are bonded at room temperature and heated to high temperature. In the latter case of (b), not only do the surfaces not bond (since the total bonding energy of about ^24mJ /m2 is too low when the surfaces are brought together), they also do not bond at elevated temperatures because There are no or too few polar reactive groups present. Between these ^two extremes there is a range of bonding energies, eg 50-1000 mJ/m2, which can produce the desired degree of controlled bonding. Accordingly, the inventors of the present invention have discovered various ways of providing an adjustable surface modification layer 30 that produces an adhesive energy that lies between these two extremes, so that a controlled bond can be produced that is sufficient to maintain mutual adhesion. Severe conditions for processing a junctioned glass substrate pair (e.g., glass carrier 10 and thin glass sheet 20) by FPD, but to an extent (even after high temperature processing, e.g. 20 with carrier 10. Furthermore, the detachment of the foil 20 from the carrier 10 may be performed by mechanical force in such a way that at least the foil 20 is not catastrophically damaged (and preferably also the carrier 10 is also not catastrophically damaged).

Equation (5) describes the adhesion energy as a function of the four surface energy parameters plus covalent and electrostatic energy (if present).

Proper bonding energy can be achieved through judicious selection of surface modifiers (ie, surface modifying layer 30 and/or surface heat treatment prior to bonding). Appropriate bonding energy can be achieved by selecting a chemical modifier of the bonding surface 14 and/or bonding surface 24 which in turn controls both van der Waals (and/or hydrogen bonding, these terms are interchangeable throughout this specification using) the adhesive energy and possibly the covalently bonded adhesive energy due to high temperature processing (eg, approximately > 400°C). For example, taking the bonding surface of SC1 cleaned glass (which is initially filled with silanol groups with a high polar component of surface energy) and coating it with a low energy fluoropolymer, through polar and nonpolar groups , which controls the partial coverage of the surface. This not only provides control over the initial van der Waals (and/or hydrogen bonding) bonding at room temperature, but also the degree/degree of covalent bonding at higher temperatures. Control of initial van der Waals (and/or hydrogen bonding) bonding at room temperature, thereby providing bonding of one surface to another for vacuum and or spin-rinse-dry (SRD) type processing, in some cases , also provides an easy-to-form bond of one surface to another surface, wherein the easy-to-form bond can be performed at room temperature instead of pressing the sheet 20 to the carrier 10 with a scraper or with a reduced pressure environment, The externally applied force is applied over the entire area of the sheet 20 . That is, the initial van der Waals bond provides at least a minimum degree of cohesion to hold the sheet and support together so that they do not separate if one is held while the other is subjected to gravity. In most cases, the degree of initial van der Waals (and/or hydrogen bonding) bonding will be such that the article can also be processed by vacuum, SRD, and ultrasound without separating the flakes from the support. Van der Waals (and/or hydrogen bonding) bonds are made by the surface modification layer 30 (including the material from which it is made and/or the surface treatment of the surface applied to it) and/or by heat treatment of the bonding surfaces before they are bonded together. This precise control of both bonding and covalent interactions at suitable levels achieves the desired bonding energy that allows the flake 20 to be bonded to the carrier 10 throughout FPD-type processing, while at the same time After molding, separation of the foil 20 from the carrier 10 is achieved (by a suitable force that avoids damage to the foil 20 and/or the carrier). Additionally, where appropriate, an electrostatic charge can be applied to one or both glass surfaces to provide another level of control of the adhesion energy.

FPD processing (e.g. p-Si and oxide TFT fabrication) typically involves thermal processing at temperatures above 400°C, above 500°C, and in some cases above or equal to 600°C, up to 650°C, which results in thin glass Glass-to-glass bonding of the sheet 20 to the glass carrier 10 occurs in the absence of the surface modification layer 30 . Thus, controlling the formation of Si-O-Si bonds yields reusable supports. One way to control the formation of Si-O-Si bonds at elevated temperatures is to reduce the concentration of surface hydroxyl groups on the surface to be bonded.

As shown in Figure 3, it is the Erle curve (R.K.Iller, "Silicon Dioxide Chemistry", Wiley International Science, New York, 1979 (Wiley-Interscience, New York, 1979)), the number of hydroxyl groups (OH groups) per square meter of nanometers decreases with increasing surface temperature. Thus, heating a silica surface (similar to a glass surface, such as bonding surface 14 and/or bonding surface 24) reduces the concentration of surface hydroxyl groups, reducing the likelihood that hydroxyl groups on the two glass surfaces will interact. This decrease in surface hydroxyl concentration in turn reduces the Si-O-Si bonds formed per unit area, reducing adhesion. However, elimination of surface hydroxyl groups requires long annealing times at high temperatures (above 750° C. to completely eliminate surface hydroxyl groups). Such long annealing times and high annealing temperatures result in an expensive process and are not practical as this would be above the strain point of typical display glass.

Through the above analysis, the inventors of the present invention found that it is possible to manufacture products comprising sheets and carriers suitable for FPD processing (including LTPS processing) by balancing the following three concepts:

(1) Modification of the support and/or sheet bonding surface by controlling the initial room temperature bonding, which can be accomplished by controlling van der Waals (and/or hydrogen bonding) surface energy of > ^40mJ /m2 per surface prior to bonding) to promote initial room temperature bonding, and sufficient to withstand non-high temperature FPD processing, such as vacuum processing, SRD processing, and/or ultrasonic processing;

(2) Surface modification of the support and/or flakes in such a way that it is thermally stable to withstand FPD processing does not occur which would lead to delamination and/or unacceptable contamination in device fabrication (e.g., for potential use articles outgassing of semiconductor and/or display manufacturing processes that are unacceptable contaminants); and

(3) High-temperature bonding can be controlled by controlling the concentration of hydroxyl groups on the surface of the support and the concentration of other substances capable of forming strong covalent bonds at elevated temperatures (such as temperatures ≥ 400°C), so that the The bonding energy between the bonding surfaces is controlled so that even after high temperature processing (especially by thermal processing at 500-650° C., such as FPD processing), the adhesion between the carrier and the sheet remains at a permissible level of at least no A separation force that would damage the flakes (preferably not damage the flakes or the support), debond the flakes from the support, and still be sufficient to maintain the bond between the support and flakes so that they do not delaminate during processing.

Furthermore, the inventors of the present invention have discovered that the use of a surface modification layer 30, together with a suitable bonding surface preparation, balances the above concepts to easily achieve a controlled bonding area, i.e., a bonding area that provides a lamella Adequate room temperature bonding between 20 and carrier 10 to allow processing of article 2 in FPD-type processing (including vacuum processing and wet processing) and also to control sheet 20 and carrier 10 (even at elevated temperatures > 400°C temperature), allowing the removal of the flakes 20 from the carrier 10 (at least without damaging the flakes, and preferably also without damaging the carrier). A series of tests were used to evaluate possible bonding surface preparations and surface modification layers that would provide a reusable carrier suitable for FPD processes. Different FPD applications have different requirements, but LTPS and oxide TFT processing appear to be by far the most stringent, therefore, tests of representative steps in these processes were chosen as they are the desired applications for Article 2. Vacuum processing, wet cleaning (including SRD and ultrasonic type processing), and wet etching are common to many FPD applications. Typically, aSi TFT fabrication requires processing as high as 320°C. In oxide TFT processes, annealing at 400°C is used, while in LTPS processing, crystallization and dopant activation steps above 600°C are used. Therefore, the following 5 tests are used to evaluate that a specific bonding surface preparation and surface modification layer 30 will allow the wafer 20 to remain bonded to the carrier 10 throughout FPD processing, and at the same time under such processing (including temperatures > 400°C After processing), the possibility of removing the sheet 20 from the carrier 10 (without damaging the sheet 20 and/or the carrier 10 ) is allowed. The tests are performed sequentially, advancing the sample from one test to the next, unless there is a failure type that would not allow subsequent testing.

(1) Vacuum test. Vacuum compatibility tests were carried out in an STS Multiplex PECVD loadlock (available from SPTS, Newport, UK), through a soft pump valve, using an Ebara A10S A dry pump (available from Ebara Technologies Inc., Sacramento, CA) pumped the load lock. The sample is placed in the load lock and the load lock is pumped down from atmospheric pressure to 70 mTorr within 45 seconds. A failure, denoted by the symbol "F" in the "Vacuum" column of the table below, is considered a failure if: (a) there is a loss of bond between the carrier and the sheet (visually observed with the naked eye, if the sheet leaves the carrier or the sheet is partially debonded from the carrier, it is considered to have failed); (b) there are air bubbles between the carrier and the sheet (determined by naked eye visual observation, the samples are photographed before and after processing, and then compared, if for The scale visible to the naked eye, the size of the defect increases, then it is determined that a failure has occurred); or (c) the movement of the sheet relative to the carrier (determined by visual observation with the naked eye, taking pictures before and after the test, if there are bonding defects (such as air bubbles) ), or if the edges are debonded or there is movement of the sheet on the support, a failure is considered to have occurred). In the tables below, the symbol "P" in the "Vacuum" column indicates that the sample passed the aforementioned criteria without failure.

(2) Wet processing test. Wet processing compatibility testing was performed using a Semitool model SRD-470S (available from Applied Materials, Santa Clara, CA). The test consisted of 60 seconds of flushing at 500 rpm, Q-cleaning to 15 Mohms at 500 rpm, 10 seconds of purge at 500 rpm, 90 seconds of drying at 1800 rpm, and 180 seconds of drying at 2400 rpm under warm nitrogen flow. A failure, indicated by the symbol "F" in the "SRD" column of the table below, is considered a failure if: (a) there is loss of the bond between the carrier and the sheet (visually observed with the naked eye, if the sheet leaves the carrier or the sheet is partially debonded from the carrier, it is considered to have failed); (b) there are air bubbles between the carrier and the sheet (determined by naked eye visual observation, the samples are photographed before and after processing, and then compared, if for If the scale visible to the naked eye, the size of the defect increases, it is determined that a failure has occurred); or (c) the sheet moves relative to the carrier (determined by visual observation with the naked eye, taking pictures of the sample before and after the test, if there is a bonding defect ( movement of air bubbles, for example), or if there is debonding of the edges or movement of the flake on the support, a failure is considered to have occurred); or (d) water penetration beneath the flake (determined by visual inspection with a 50X light microscope, if observable If there is liquid or residue, it is determined that a failure has occurred). In the tables below, the symbol "P" in the "SRD" column indicates that the sample passed the aforementioned criteria without failure.

(3) Test to 400°C temperature. The 400° C. processing compatibility test was performed using an Alwin21 Accuthermo 610 RTP (available from Alwin21, Santa Clara, CA). The flake-bonded carrier was heated in a chamber as follows: from room temperature to 400°C at 6.2°C/min, held at 400°C for 600 seconds, and cooled to 300°C at 1°C/min. The support and flakes were then cooled to room temperature. Failure, indicated by the symbol "F" in the "400°C" column of the table below, is considered a failure if: (a) the bond between the carrier and the sheet is lost (visually observed with the naked eye, if the sheet leaves failure if the carrier or the sheet is partially debonded from the carrier); (b) there are air bubbles between the carrier and the sheet (determined by naked-eye visual observation, taking pictures of the samples before and after processing, and then comparing, if Failure is determined to have occurred if the size of the defect increases on a scale visible to the naked eye); or (c) an increase in adhesion between the carrier and the sheet that prevents the sheet from being made without damaging the sheet or the carrier. Debonding from the support occurs (by inserting a razor blade between the sheet and the support, and/or attaching 2-3" to a piece of Kapton ^™ strip (1" wide x 6" long) attached to 100 mm2 of thin glass (available from (Saint Gobain Performance Plastic, Hoosik NY, K102 series) glued to the sheet and pull bar), if the sheet or carrier is damaged during an attempt to separate the sheet from the carrier, or by either A failure is considered to have occurred when the debonding method fails to debond the flake and carrier. In addition, debonding tests were performed on representative samples after the flake was bonded to the carrier and before thermal cycling to determine the specific material (including any relevant surface treatments) did allow debonding of the flakes from the support prior to temperature cycling. In the table below, the symbol "P" in the "400°C" column indicates that the sample passed the aforementioned criteria without failure.

(4) Test to 600°C temperature. Alwin21 Accuthermo610 RTP was used for 600°C processing compatibility test. The flakes and support were heated in a chamber cycle from room temperature to 600°C at 9.5°C/min, held at 600°C for 600 seconds, then cooled to 300°C at 1°C/min. The support and flakes were then cooled to room temperature. Failure, denoted by the symbol "F" in the "600°C" column of the table below, is considered a failure if: (a) the bond between the carrier and the sheet is lost (by visual inspection with the naked eye, if the sheet leaves failure if the carrier or the sheet is partially debonded from the carrier); (b) there are air bubbles between the carrier and the sheet (determined by naked-eye visual observation, taking pictures of the samples before and after processing, and then comparing, if Failure is determined to have occurred if the size of the defect increases on a scale visible to the naked eye); or (c) an increase in adhesion between the carrier and the sheet that prevents the sheet from being made without damaging the sheet or the carrier. Debonding from the carrier (by inserting a razor blade between the sheet and carrier, and/or adhering a piece of KaptonTM strip as described above to the sheet and pulling the strip), if the sheet or carrier occurs when attempting to separate the sheet and carrier failure, or failure to debond the sheet and carrier by any debonding method. In addition, debonding tests are performed on representative samples after the flake is bonded to the support and before thermal cycling to determine that the particular material (and any associated surface treatment) does allow debonding of the flake to support prior to temperature cycling Knot. In the table below, the symbol "P" in the "600°C" column indicates that the sample passed the aforementioned criteria without failure.

(5) Ultrasonic test. Ultrasonic compatibility testing was performed by cleaning the articles in a four-pot line in which the articles were processed sequentially in each tank from tank #1 to tank #4. 4 tanks each had tank dimensions of 18.4"L x 10"W x 15"D. Two clean tanks (#1 and #2) contained 1% Semiclean KG ( Purchased from Yokohama Oils and Fats Industry Co., Ltd. (Yokohama Oils and Fats Industry Co., Ltd., Japan) in Yokohama, Japan). With NEYprosonik 2 104kHz ultrasonic generator (purchased from Blackstone-NEY Ultrasonic Company (Blackstone-NEY Ultrasonics, Jamestown, New York, Jamestown, NY)) vibrate cleaning tank #1 with NEY prosonik 2 104kHz ultrasonic generator vibration cleaning tank #2. Two cleaning tanks (tank #3 and tank #4) contain DI water at 50°C. Use NEY sweepsonik 2D 72kHz Jars #3 were vibrated with an ultrasonic generator and jar #4 was vibrated with a NEY sweepsonik 2D 104kHz ultrasonic generator. Jars #1-4 were subjected to a 10 minute process each, after which samples were removed from jar #4 and then spin cleaned and dried ( SRD). Failure, denoted by the symbol "F" in the "Ultrasonic" column of the table below, is considered a failure if: (a) there is loss of the bond between the carrier and the Failure occurs when the flakes leave the carrier or the flakes are partially debonded from the carrier); (b) there are air bubbles between the carrier and the flakes (determined by naked-eye visual observation, taking pictures of the samples before and after processing, and then comparing , failure is determined to have occurred if the size of the defect increases for the scale visible to the naked eye); or (c) the formation of other gross defects (determined by visual observation with a 50X optical microscope, if a previously unknown defect is trapped between the thin glass and the carrier). observed particles, the failure is considered to have occurred); or (d) water penetration under the sheet (as determined by visual observation with a 50X light microscope, if liquid or residue can be observed, the failure is determined to have occurred). In the table below, " The symbol "P" in the "Ultrasound" column indicates that the sample passed the aforementioned criteria without failure. Also, in the tables below, a blank in the "Ultrasound" column indicates that the sample was not tested in this manner.

Bond energy test

Adhesion energy is the energy that causes separation of the flake from the support. Bond energy can be measured in various ways. However, as used herein, the bonding energy is measured as follows.

The bond energy was measured using the double cantilever method (also known as the wedge method). In this method, a wedge of known thickness is placed between the bonded foil and the carrier glass, at the edge. The wedge produces the property layering distance, L. This delamination distance was measured and Equation 6 was used to calculate the bond energy γ _BE .

${\mathrm{<span\; class="notranslate">\; \&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}\mathrm{<span\; class="notranslate">\; E.</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 3</span>}{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; w</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}{\mathrm{<span\; class="notranslate">\; E.</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; 3</span>}}{\mathrm{<span\; class="notranslate">\; E.</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; 2</span>}}^{\mathrm{<span\; class="notranslate">\; 3</span>}}}{\mathrm{<span\; class="notranslate">\; 16</span>}{\mathrm{<span\; class="notranslate">\; L</span>}}^{\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; E.</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; E.</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; 2</span>}}^{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; )</span>}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 6</span>}<span\; class="notranslate">\; )</span>$

The Young's modulus, E, for both the support (1) and the sheet (2) composed of EXG is 73.6 GPa. A typical thickness of the support, t _s1 , is 0.7 mm, and the thickness of the sheet, t _s2 , is 0.13 mm. A Martor 37010.20 razor blade was used as the wedge, forming a thickness _tw of 95um. Samples with very high bond energy were pre-cracked with a separate wedge. This enables easier insertion of wedges and yields characteristic layered lengths. For the bond energy data recorded, a value of 2500 indicated the limit of the test and for this particular sample, it was not possible to debond the flake from the support.

Preparation of bonding surface by heat reduction via hydroxyl groups

Modification of one or more of the bonding surfaces 14, 24 with a surface modification layer 30 was demonstrated by processing an article 2 having a glass carrier 10 and a thin glass sheet 20 without the surface modification layer 30 in between such that Article 2 can successfully withstand the benefits of FPD processing (ie, sheet 20 remains bonded to carrier 10 during processing and can also be separated from carrier 10 after processing including high temperature processing). Specifically, an attempt was first made to prepare the bonding surfaces 14, 24 by heating to reduce the hydroxyl groups, but without the use of the surface modification layer 30. The carrier 10 and sheet 20 are cleaned, the bonding surfaces 14 and 24 are bonded to each other, and the article 2 is tested. A typical cleaning process for preparing glass for bonding is the SC1 cleaning process, in which the glass is treated in dilute hydrogen peroxide and a base (usually ammonium hydroxide, but tetramethylammonium hydroxide solution can also be used, such as JT Baker JTB-100 or JTB-111) for cleaning. Cleaning removes particles from the bonding surface such that the surface energy is known, ie it provides a baseline of the surface energy. The cleaning method does not have to be SC1, other types of cleaning may be used, such as ones that may have only a very small impact on the silanol groups on the surface. The test results are shown in Table 1 below.

Strong, but separable initial room temperature or van der Waals and/or hydrogen bonds are created by simple cleaning of thin glass sheets 100 mm2 x 100 microns thick and glass supports 150 mm in diameter single mean flat (SMF) wafers with a thickness of 0.50 or 0.63mm, which consist of Display glass (alkali-free aluminoborosilicate glass with an average surface roughness Ra of about 0.2 nm available from Corning Incorporated, Corning, NY). In this example, the glass was cleaned for 10 minutes in a 65°C bath of 40:1:2 DI water:JTB-111:hydrogen peroxide. Thin glass or glass carrier can be annealed in nitrogen at 400°C for 10 minutes or not in it to remove residual water. The symbol "400°C" in the column "Carrier" or "Thin Glass" in Table 1 below indicates that the sample was Annealed in nitrogen at 400°C for 10 minutes. FPD processing compatibility testing confirmed that the SC1-SC1 initial, room temperature bond was mechanically strong enough to pass vacuum, SRD, and ultrasonic testing. However, heating at greater than or equal to 400°C creates a permanent bond between the thin glass and the carrier, ie the thin glass sheet cannot be removed from the carrier without damaging the thin glass sheet and/or the carrier. This is even the case for Example 1c, where the support and the thin glass each have an annealing step to reduce the surface hydroxyl concentration. Therefore, the preparation of the bonding surfaces 14, 24 by heating only as described above, and then allowing the carrier 10 and foil 12 to bond without the surface modification layer 30, is not suitable for FPD processing (where the temperature will be ≥ 400°C). Not suitable for controlled bonding.

Table 1: Processing Compatibility Testing of SC1 Treated Glass Bonding Surfaces

Example carrier thin glass vacuum SRD 400C 600C ultrasound 1a SC1 SC1 P P f f P 1b SC1,400C SC1 P P f f P 1c SC1,400C SC1,400C P P f f P

Preparation of bonding surface by hydroxyl reduction and surface modification layers

Hydroxyl reduction, such as by heat treatment, may be used with the surface modification layer 30 to control the interaction of the bonding surfaces 14,24. For example, the bonding energy of the bonding surfaces 14, 24 can be controlled (with both van der Waals and/or hydrogen bonding at room temperature due to the polar/dispersive energy component, and covalent bonding at high temperature due to the covalent energy component). bonding) to provide different bond strengths, from room temperature bonding (which makes it difficult to achieve simple room temperature bonding and separate the bonded surfaces after high temperature processing) to preventing the surface from separating after high temperature processing without damage Case. In some applications, it may be desirable to have no or very weak bonds (when the surface is in a "non-bonded" region, see US '727 for the sheet/carrier concept, and as described below). In other applications, such as providing reusable carriers for FPD processes, etc. (where processing temperatures ≥500°C or ≥600°C, and up to 650°C are possible), it is desirable to have sufficient van der Waals and/or Hydrogen bonding to initially bring the flake and support together and also prevent or limit high temperature covalent bonding. For other applications, it may be desirable to have sufficient room temperature bonding to bring the flake and support together initially, and also to establish a strong covalent bond at elevated temperatures ("bond region" when the surface is in the "bond" region). " See US '727 for the flake/carrier concept, and as described below). While not wishing to be bound by theory, it is believed that, in some cases, the surface modification layer can be used to control room temperature bonding when the sheet and support are initially placed together, while the reduction of hydroxyl groups on the surface (e.g., by Heating the surface or through the reaction of the hydroxyl groups with the surface modification layer) can be used to control covalent bonding, especially at high temperatures.

The material used for the surface modification layer 30 may provide the bonding surfaces 14, 24 with energy (eg, energy < 40 mJ/m ² , measured from one surface, including polar and dispersive components) of the surface to produce only a weak bond. In one example, hexamethyldisilazane (HMDS) can be used to create this low energy surface by reacting with surface hydroxyl groups leaving a trimethylsilyl (TMS) terminated surface. HMDS as a surface modification layer can be used with surface heating to reduce hydroxyl concentration to control room temperature and high temperature adhesion. By selecting an appropriate bonding surface preparation for the bonding surfaces 14, 24, respectively, an article with a range of capabilities can be achieved. More specifically, out of interest in providing a reusable carrier for LTPS processing, a suitable bond can be achieved between the thin glass sheet 20 and the glass carrier 10 to withstand (or pass) vacuum SRD, 400°C (part a and c) and each of the 600°C (parts a and c) processing tests.

In one example, after SC1 cleaning followed by HMDS treatment of both the thin glass and the support, a weakly bonded surface was created that would be challenging to bond with van der Waals (and/or hydrogen bonding) forces at room temperature . Mechanical force is applied to bond the thin glass to the carrier. As shown in Example 2a of Table 2, the bond is weak enough that deflection of the support was observed during vacuum testing and SRD processing, observed during thermal processing at 400°C and 600°C (possibly due to outgassing) Blistering, and particle defects were observed after ultrasonic processing.

In another example, HMDS treatment of only one surface (the support in the cited example) produced a strong room temperature bond that survived vacuum and SRD processing. However, thermal processing at 400°C and higher results in permanent bonding of the thin glass to the carrier. This is not unexpected since the maximum surface coverage of trimethylsilyl groups on silica has been calculated to be 2.8 by Sindorf and Maciel, J.Phys.Chem. /nm ² , and was measured as 2.7/nm ² by Suratwala et al. in Journal of Non-Crystalline Solids (Journal of Non-Crystalline Solids) 316 (2003) 349–363, compared to the concentration of hydroxyl groups for fully hydroxylated silica of 4.6-4.9/nm ² . That is, while the trimethylsilyl group does bind some surface hydroxyl groups, some hydroxyl groups remain unbound. Thus, given sufficient time and temperature, condensation of the surface silanol groups would be expected to permanently bond the thin glass to the support.

By reducing the surface hydroxyl concentration by heating the glass surface prior to HMDS exposure, different surface energies can be generated, resulting in an increase in the polar component of the surface energy. This simultaneously reduces the driving force for forming covalent Si-O-Si bonds at high temperatures and leads to stronger room temperature bonds, eg van der Waals (and/or hydrogen) bonding. Figure 4 shows after annealing and after HMDS treatment Surface energy of display glass supports. An increase in annealing temperature before HMDS exposure increases the total (polar and dispersion) surface energy after HMDS exposure (line 402 ) by increasing the polar contribution (line 404 ). It is also seen that the dispersion contribution (line 406 ) to the total surface energy remains largely unchanged by heat treatment. While not wishing to be bound by theory, increasing the polar component, and thus the total energy in the surface after HMDS treatment, appears to be due to the sub-monolayer TMS being covered by HMDS, leaving some exposure even after HMDS treatment glass surface area.

In Example 2b, a thin glass sheet was heated in vacuum at a temperature of 150° C. for one hour before being bonded to a non-heat-treated support with HMDS coating. This heat treatment of the thin glass sheet is not sufficient to prevent permanent bonding between the thin glass sheet and the carrier at a temperature ≥ 400°C.

As shown in Examples 2c-2e of Table 2, changing the annealing temperature of the glass surface before HMDS exposure can change the bonding energy of the glass surface, thereby controlling the bonding between the glass carrier and the thin glass sheet.

In Example 2c, the support was annealed in vacuum at a temperature of 190° C. for one hour, followed by HMDS exposure to provide the surface modification layer 30 . In addition, thin glass sheets were annealed in vacuum at 450 °C for one hour before being bonded to the carrier. The resulting article withstood the vacuum, SRD, and 400°C tests (parts a and c, but failed part b because of increased foaming), but failed the 600°C test. Thus, while the resistance to high temperature sticking is increased compared to Example 2b, it is not sufficient to produce articles with a reusable carrier for processing at temperatures > 600°C (eg LTPS processing).

In Example 2d, the support was annealed in vacuum at a temperature of 340° C. for one hour, followed by HMDS exposure to provide the surface modification layer 30 . Again, the thin glass pieces were annealed in vacuum at 450°C for one hour before being bonded to the carrier. Results were similar to Example 2c, the article withstood the vacuum, SRD and 400°C tests (parts a and c, but failed part b due to increased air bubbles), but failed the 600°C test.

As shown in Example 2e, both the thin glass and the support were annealed in vacuum at 450°C for one hour before exposing the support to HMDS, which then bonded the support to the thin glass sheet, improving the temperature resistance to permanent bonding. Annealing of both surfaces at 450°C prevents permanent bonding after RTP annealing at 600°C for 10 minutes, that is, the sample passes the 600°C processing test (parts a and c, but fails part b because of increased bubbles; Similar results were obtained for the 400°C test).

Table 2: Processing compatibility test of HMDS surface modification layer

In the above examples 2a-2e, the carrier and sheet were respectively Glass, where the carrier is a 150 mm diameter, 630 micron thick SMF wafer and the sheet is 100 mm2, 100 micron thick. HMDS was applied by pulsed vapor deposition in a YES-5 HMDS oven (available from Yield Engineering Systems, San Jose CA), which was one atomic layer thick (i.e., about 0.2-1 nm) , but the surface coverage may be less than a monolayer, i.e. part of the surface hydroxyl groups is not covered by HMDS, as described by Maceil and supra. Due to the small thickness of the surface modification layer, there is little risk of outgassing which would cause contamination in device fabrication. In addition, as indicated by the "SC1" notation in Table 2, the support and flakes were cleaned using the SC1 process, respectively, before heat treatment and any subsequent HMDS treatment.

A comparison of Example 2a and Example 2b shows that the bonding energy between the flake and the support can be controlled by varying the number of surfaces comprising the surface modification layer. Controlling the bond energy can be used to control the bond force between two bonded surfaces. Furthermore, a comparison of Examples 2b-2e shows that the bonding energy of the surface can be controlled by varying the parameters of the heat treatment to which the bonding surface is subjected prior to application of the surface modifying material. In addition, heat treatment can be used to reduce the number of surface hydroxyl groups and thereby control the degree of covalent bonding, especially at elevated temperatures.

Other materials that control the surface energy on the bonding surface in different ways can be used for the surface modification layer 30 to control the room temperature and high temperature adhesion between the two surfaces. For example, if one or both of the bonding surfaces are modified to produce moderate adhesion to a surface modification layer that covers or sterically hinders species such as hydroxyl groups, To prevent the formation of strong permanent covalent bonds between the support and the flakes at elevated temperatures, a reusable support can be produced. One way to create tunable surface energies and cap surface hydroxyl groups to prevent covalent bond formation is to deposit plasma polymer films, such as fluoropolymer films. Plasma polymerization deposits thin polymer films under atmospheric or reduced pressure and plasma excitation from a source gas (DC or RF parallel plate, inductively coupled plasma (ICP) electron cyclotron resonance (ECR downstream microwave or RF plasma), the The source gas is, for example, a source of fluorocarbons (including CF4, CHF3, C2F6, C3F6, C2F2, CH3F, C4F8, chlorofluorocarbons or hydrochlorofluorocarbons), hydrocarbons (such as alkanes, including methane, ethane, propane, butane ; olefins, including ethylene, propylene; alkynes, including acetylene; and aromatics, including benzene, toluene), hydrogen, and other gas sources (such as SF6). Plasma polymerization produces layers of highly crosslinked materials. Control of reaction conditions and source gases Can be used to control film thickness, density and chemistry to tailor functional groups to desired applications.

Figure 5 shows the total surface energy (line 502) of a plasma-polymerized fluoropolymer (PPFP) film deposited from a CF4-C4F8 mixture using an Oxford ICP380 etch tool (obtained from Oxford Instruments, Oxfordshire UK). ), which includes a polar component (line 504) and a dispersion component (line 506). deposit the film on On glass slides, spectral ellipsometry showed a film thickness of 1-10 nm. As can be seen from Fig. 5, glass supports treated with plasma-polymerized fluoropolymer films containing less than 40% C4F8 exhibit surface energies >40 ^mJ /m2 and produce a flow rate between the thin glass and the support at room temperature. Controlled bonding by van der Waals or hydrogen bonding. Promoted bonding was observed when the carrier and thin glass were initially bonded at room temperature. That is, when the flakes were placed on the support and they were pressed at one point, the wavefront moved through the support, but at a lower velocity than that observed for the SC1 -treated surface without the surface modification layer thereon. The controlled bond is sufficient to withstand all standard FPD processes, including vacuum processing, wet processing, ultrasonic processing, and thermal processing up to 600°C, that is, the controlled bond passed the 600°C processing test without occurrence of thin glass and Movement or delamination of the carrier. Debonding was accomplished by peeling with a razor blade and/or Kapton ^(TM) tape as described above. The processing compatibility of two different PPFP films (deposited as described above) is shown in Table 3. The formed PPFP 1 of Example 3a has C4F8/(C4F8+CF4)=0, that is, formed of CF4/H2 instead of C4F8; the deposited PPFP 2 of Example 3b has C4F8/(C4F8+CF4) = 0.38. Both types of PPFP films withstood vacuum, SRD, 400°C and 600°C processing tests. However, delamination was observed after 20 min of ultrasonic cleaning of PPFP 2, indicating insufficient adhesion to withstand such processing. However, for some applications where ultrasonic machining is not required, a surface modified layer of PPFP 2 may be useful.

Table 3: Processing compatibility test of PPFP surface modification layer

In the above examples 3a and 3b, the carrier and sheet were respectively Glass, where the carrier is a 150 mm diameter, 630 micron thick SMF wafer and the sheet is 100 mm2, 100 micron thick. Due to the small thickness of the surface modification layer, there is little risk of outgassing which would cause contamination in device fabrication. Furthermore, since the surface modification layer does not appear to decompose, there is also no risk of outgassing, as such. In addition, as shown in Table 3, the flakes were cleaned using the SC1 process, respectively, before vacuum heat treatment at 150 °C for 1 h.

Other materials that control the surface energy in different ways can also be used as surface modification layers to control the room temperature and high temperature adhesion between the flake and support. For example, silane treatment of glass supports and/or glass flakes can create bonding surfaces capable of controlled bonding. The silane is chosen to yield the right surface energy to be thermally stable enough for the application. The support or thin glass to be treated can be treated by, for example, O2 plasma or UV-ozone, and SC1 or Standard Clean 2 (SC2, known in the art) cleaning to remove interfering silanes and surface silanols Group reactive organics and other impurities (eg metals). Other chemical based cleanings such as HF or H2SO4 cleaning chemistries can be used. The support or thin glass can be heated to control the concentration of surface hydroxyl groups prior to the application of the silane (as described above for the surface modification layer of HMDS), and/or can be applied after the application of the silane to complete the bonding of the silane to the surface hydroxyl groups. condensation. The concentration of unreacted hydroxyl groups after silanization prior to bonding can be made low enough to prevent permanent bonding between the thin glass and the support at temperatures > 400°C, i.e. to form a controlled bond. Knot. The method is described below.

Example 4a

The glass carrier whose bonded surface had been treated with O2 plasma and SC1 was then treated with 1% dodecyltriethoxysilane (DDTS) in toluene, and annealed in vacuum at 150 °C for 1 hour to complete the condensation. The DDTS treated surface exhibited a surface energy of 45 mJ/m ² . As shown in Table 4, the glass flakes (SC1 cleaned and vacuum heated at 400°C for 1 hour) bonded to the carrier bonding surface with the DDTS surface modified layer thereon. The article survived wet processing and vacuum processing tests, but failed thermal processing above 400°C without formation of bubbles under the support due to thermal decomposition of the silane. For all linear alkoxy and chloroalkylsilanes R1 _x Si(OR2) _y (Cl) _z where x=1-3, y+z=4-x (excluding methyl, dimethyl and trimethyl In the case of silanes (x = 1-3, R1 = CH ₃ ), which lead to coatings with good thermal stability), such thermal decomposition is expected.

Example 4b

The O2 plasma and SC1-treated glass supports on their bonded surfaces were then treated with 1% 3,3,3 trifluoropropyltriethoxysilane (TFTS) in toluene and annealed in vacuum at 150 °C for 1 hours to complete the condensation. The TFTS-treated surface exhibited a surface energy of 47 mJ/m ² . As shown in Table 4, the glass flakes (SC1 cleaned and then vacuum heated at 400° C. for 1 hour) bonded to the carrier bonding surface with the TFTS surface modification layer thereon. The article withstood vacuum, SRD and 400°C processing tests without permanent bonding of the glass flakes to the glass carrier. However, the 600°C test produced bubbles that formed beneath the support due to thermal decomposition of the silane. This is not unexpected due to the limited thermal stability of propyl groups. Although this sample failed the 600°C test due to blistering, the material and heat treatment of this example can be used in some applications where blistering and its detrimental effects (such as a decrease in surface flatness or increased waviness) can be tolerated.

Example 4c

The glass carrier whose bonded surface was treated with O2 plasma and SC1 was then treated with 1% phenyltriethoxysilane (PTS) in toluene, and annealed in vacuum at 200 °C for 1 hour to complete the condensation. The PTS-treated surface exhibited a surface energy of 54 mJ/m ² . As shown in Table 4, the glass flakes (SC1 cleaned and then vacuum heated at 400° C. for 1 hour) bonded to the carrier bonding surface with the PTS surface modification layer thereon. The article has withstood vacuum processing, SRD processing and thermal processing up to 600°C without permanent bonding of the glass flakes to the glass carrier.

Example 4d

The glass carrier whose bonded surface had been treated with O2 plasma and SC1 was then treated with 1% diphenyldiethoxysilane (DPDS) in toluene, and annealed in vacuum at 200°C for 1 hour to complete the condensation. The DPDS treated surface exhibited a surface energy of 47 mJ/m ² . As shown in Table 4, the glass flakes (SC1 cleaned and then vacuum heated at 400° C. for 1 hour) bonded to the carrier bonding surface with the DPDS surface modification layer thereon. The article withstood vacuum and SRD tests, as well as thermal processing up to 600°C, without permanent bonding of the glass flakes to the glass carrier.

Example 4e

Then, the glass carrier whose bonding surface was treated with O2 plasma and SC1 was treated with 1% 4-pentafluorophenyltriethoxysilane (PFPTS) in toluene, and annealed in vacuum at 200 ° C for 1 hour to complete condensation. The PFPTS-treated surface exhibited a surface energy of 57 mJ/m ² . As shown in Table 4, the glass flakes (SC1 cleaned and then vacuum heated at 400° C. for 1 hour) bonded to the carrier bonding surface with the PFPTS surface modification layer thereon. The article withstood vacuum and SRD tests, as well as thermal processing up to 600°C, without permanent bonding of the glass flakes to the glass carrier.

Table 4: Processing compatibility test of silane surface modification layer

In the above examples 4a-4e, the carrier and sheet were respectively Glass, where the carrier is a 150 mm diameter, 630 micron thick SMF wafer and the sheet is 100 mm2, 100 micron thick. The silane layer is a self-assembled monolayer (SAM), and thus has a thickness of about less than about 2 nm. In the above examples, organosilanes with aryl or alkyl non-polar tails and mono-, di-, or tri-alkoxide head groups were used to generate SAMs. They react with the silanol surface on the glass for direct attachment of organofunctional groups. Weaker interactions between the nonpolar headgroups allow organic layers to be organized. Due to the small thickness of the surface modification layer, there is little risk of outgassing which would cause contamination in device fabrication. Furthermore, since the surface modification layers in Examples 4c, 4d and 4e do not appear to decompose, again, there is no risk of outgassing. In addition, as shown in Table 4, the glass flakes were cleaned using the SC1 process, respectively, before vacuum heat treatment at 400 °C for 1 h.

From the comparison of Examples 4a-4e, it can be seen that controlling the surface energy of the bonding surface to greater than 40mJ/ ^m2 to facilitate initial room temperature bonding is not only for producing controlled adhesion that can withstand FPD processing. Junction considerations also enable removal of the flakes from the carrier without causing damage. In particular, it can be seen from Examples 4a-4e that the supports have surface energies greater than 40 mJ/m ² , respectively, which facilitate initial room temperature bonding, allowing the articles to withstand vacuum and SRD processing. However, Examples 4a and 4b failed the 600°C processing test. As noted above, for certain applications, the bond is made to withstand high temperature processing (a suitable process for the intended use of the article, e.g., ≥400°C, ≥500°C, or ≥600°C, up to 650°C) and not It is also important to degrade the bond enough not to hold the flake and support together, and to control the covalent bonding that occurs at such high temperatures so that there is no permanent bond between the flake and support. As shown in the examples in Table 4, aromatic silanes (specifically, phenyl silanes) can be used to provide controlled bonding that will aid in initial room temperature bonding and will withstand FPD processing and still allow Remove the flakes from the carrier in case of damage.

Fluorocarbon surface modification layer, and its treatment

Another example of the use of plasma polymerized films to tune the surface energy of bonding surfaces and create alternative polar bonding sites on them is to deposit a thin film of a surface modification layer from a mixture of fluorocarbon gas sources, followed by the use of various methods Nitrogen-based polar groups are formed on the surface modification layer.

Surface modification layers can be formed by plasma polymerization of various mixtures of fluorocarbon gas sources to provide various surface energies, including surface energies greater than about 50 ^mJ /m , as established by S. Wu (1971) The model is calculated from the fit of the contact angle (CA) of three different test liquids, in this case deionized water (water), hexadecane (HD) and diiodomethane (DIM). (See S. Wu, J. Polym. Sci. C, 34, 19, 1971, hereinafter referred to as "Wu model"). Surface energies greater than about 50 mJ/m2 ^on the carrier bonding surface are advantageous for bonding the carrier to the thin glass sheet because this facilitates room temperature bonding of the carrier to the thin glass sheet and achieves carrier/thin glass sheet FPD processing (they do not debond during processing). In some cases, depending on the surface modification layer composition and deposition conditions, surface modification layers with this surface energy can be debonded by peeling, even at temperatures as high as about 600 °C (and in some cases even higher ) temperature after processing the carrier and the thin glass sheet. Typically, the source gas includes a mixture of etching gas and polymer-forming gas. As described above with respect to FIG. 5, the etching gas may be CF4 and the polymer forming gas may be C4F8. Alternatively, as shown in FIG. 13, the etching gas may be CF4 and the polymer forming gas may be CHF3. As shown in both Figures 5 and 13, in general, the lower the percentage of polymer-forming gas, the higher the total surface energy 502, 1312 of the resulting bonding surface, where the total surface energy is the polar component 504 , 1314 (triangular data points) and the combination of dispersion components 506, 1316 (square data points). The percentage of polymer-forming gas (e.g. CHF3) during plasma polymerization can be controlled in a similar manner by using an inert gas (e.g. Ar) as shown in Figure 13A which shows the total surface energy in mJ /m2. Without wishing to be bound by theory, the inert gas may act as an etchant and/or diluent. In any case, it is clear that the surface energy of the carrier glass can be modified by CHF3 alone without any CF4 in the gas stream. Deposition of surface modification layers can be performed at atmospheric or reduced pressure using plasma excitation such as DC or RF parallel plate, inductively coupled plasma (ICP), electron cyclotron resonance (ECR), downstream microwave or RF plasma. The plasma polymerized surface modification layer can be arranged on the support and/or the foil. As described above with respect to the examples in Table 3, plasma polymerization produced layers of highly cross-linked material. Control of reaction conditions and source gases can be used to control the film thickness, density, and chemistry of the surface modification layer to tailor the functional groups to desired applications. And by controlling the film properties, the surface energy of the support bonding surface can be tuned. However, surface energy is only one consideration in controlling the degree of bonding.

The degree of controlled bonding, or moderate bonding, can be further tuned by controlling the polar bond used to achieve the desired surface energy. One way to control polar linkages is to expose the (as-formed) surface-modified layer to further treatment to bind polar groups, for example by nitrogen-containing plasma. This treatment increases adhesion by forming nitrogen-based polar functional groups on the thin surface modification layer. Nitrogen-based polar groups formed during subsequent processing do not condense with silanols to cause permanent covalent bonding; thus enabling control of the relationship between the wafer and the support during subsequent processing to place films or structures on the wafer. degree of bonding between them. Methods for forming nitrogen-based polar groups include, for example, nitrogen plasma treatment (Examples 5b-d, k, 1), ammonia plasma treatment (Examples 5e, f, h-j), and nitrogen/hydrogen plasma treatment (Examples 5e, f, h-j). Example 5m).

It was observed that for thin glass sheets and glass supports bonded to nitrogen-containing plasma-treated surface modification layers, no permanent adhesion occurred after annealing at 600°C, ie passing part (c) of the 600°C temperature test. Furthermore, this moderate bond is strong enough to withstand FPD processing (including the vacuum test (1), wet processing test (2) and ultrasonic test (5) described above), and remains stable by applying sufficient peel force. Releasable. Debonding enables the removal of devices fabricated on thin glass and the reuse of the carrier. Nitrogen plasma treatment of the surface modification layer can achieve one or more of the following benefits: high surface energy and low water contact angle, formation of strong adhesion between flakes and support, with minimal bubble defects after initial bonding (see Implementation Examples 5b-f and i-l); reduced defect formation when thermally processed due to improved thermal stability of the surface modification layer (Examples 5c, 5d, 5k, 5l i.e. samples treated with N2 exhibited reduced bubble formation, visual observation); and/or an easier processing window, since the separation of surface modification layer formation and treatment enables different processes to optimize the support/surface modification layer and surface modification layer/thin glass interface ( Examples 5b-f and h-m). That is, the substrate material used in the deposition process of the surface modification layer itself can be formulated to optimize the interaction between the surface modification layer and the support bonding surface. Then, separately, after the surface modification layer has been deposited on the support, the properties of the surface modification layer can be modified by treatment to optimize the interaction between the surface modification layer and the flakes to be deposited thereon .

In the examples in Table 5 below, various conditions were used to deposit plasma polymerized films on glass supports. The glass carrier is made of (Aluminoborosilicate alkali-free display glass available from Corning Incorporated, Corning NY) Substrates manufactured. Prior to surface modification layer deposition, the support is cleaned using SC1 and/or SC2 chemistry and standard cleaning techniques. Films were deposited in an Oxford Plasmalab 380 Inductively Coupled Plasma (ICP) system with a 13.56 MHz RF source on both the coil and platen, and the platen temperature was fixed at 30C. Nitrogen and ammonia plasma treatment of the surface modification layer for samples 5a-5j was carried out in an STS Multiplex PECVD apparatus (available from STPS, Newport, UK) in a triode electrode configuration mode , wherein the carrier on the platen is heated to 200C, and 380kHz RF energy of a specific wattage is applied to it, and a shower head is arranged on the platen, and 13.5MHz RF energy of a specific wattage is applied to it. For applied energy in both Oxford ICP and STS PECVD, quantities are shown as #/#W, where the number before the slash is the wattage applied to the top electrode (coil on ICP or showerhead on PECVD), and The number after the slash is the wattage applied to the deck. When only one number is displayed, this is the number of the top electrode. The gas flow rate into the chamber is shown in Table 5 (flow rates are standard cubic centimeters per minute, sccm). Thus, for example, the symbols in the "Surface Treatment" column of Table 5 for Example 5g read as follows: In an Oxford ICP apparatus, 30 sccm of CF4, 10 sccm of C4F8, and 20 sccm of H2 were flowed together at a pressure of 5 millitorr. In the chamber; 1000 W of 13.5 MHz RF energy was applied to the coil, 50 W of 13.56 MHz RF energy was applied to the 30C platen on which the carrier was placed; and the deposition time was 60 seconds. The symbols in the surface treatment column of the remaining examples can be interpreted in a similar manner. For another example, in the "plasma treatment" column, the symbols for the treatment of Example 5h are interpreted as follows: after the surface modification layer is formed according to the parameters in the surface treatment column of Example 5h, then 100 sccm is supplied to the STS PECVD chamber NH3, the pressure of the STS PECVD chamber was 1 Torr, and the temperature was 200° C.; 100 W of 13.56 MHz was applied to the showerhead; and the treatment was performed for 30 seconds. The symbols in the "plasma treatment" column of the remaining examples are interpreted in a similar manner. Surfaces were calculated by fitting the Wu model to the contact angles (CA) of three different test liquids, in this case deionized water (water), hexadecane (HD) and diiodomethane (DIM) Energy, both polar and dispersive, in mJ/m ² (millijoules per square meter). For surface energy, the polar (P) and dispersive (D) components and the sum (T) are shown.

In Examples 5b-5f and 5h-5l of Table 5, nitrogen-based polar groups are formed on the surface modification layer, wherein these polar groups generate Moderate bonding between them to create a temporary bond that is strong enough to withstand FPD processing but weak enough to allow debonding. After treatment, the concentration of polar groups is greater on the surface of the surface modification layer than in the bulk of the surface modification layer.

Examples of treatment by NH3 plasma (5e, f and h-j)

From 30sccm CF4 10sccm C4F8 20sccm H2 at 5mT with 1500W coil and 50W platen RF power (comparative example 5a), and additionally from 30sccm CF4 10sccm C4F8 20sccm H2 at 5mT with 1000W coil and 50W platen RF power (comparative example 5g), a moderate surface energy SML was deposited in an ICP plasma system. The surface energies of the untreated fluoropolymer membranes are shown in Table 5. The samples were transferred to an STS PECVD system and exposed to ammonia plasma under the conditions listed in Table 5 (Examples 5e, 5f, 5h-j). By Wu's equation, the surface tension measured with DI water and hexadecane increases from about 40 to about 65-80 mJ/ ^m2 , depending on the ammonia plasma conditions. For these NH3 plasma modified samples, thin glass slides were bonded separately. After the 600°C temperature test, little visual change was observed in the bubble area (no formal degassing test was performed), and in all of these samples the thin glass sheets were easily debonded by hand.

Examples of N2 plasma treatment (5c, d, k, l)

From 30sccm CF4 10sccm C4F8 20sccm H2 at 5mT with 1500W coil and 50W platen RF power (comparative example 5a), and additionally from 30sccm CF4 10sccm C4F8 20sccm H2 at 5mT with 1000W coil and 50W platen RF power (comparative example 5g), a moderate surface energy SML was deposited in an ICP plasma system. The surface energies of the untreated fluoropolymer membranes are shown in Table 5. Samples 5c, d, k, and l were treated with N2 plasma in situ in the ICP system under the conditions listed in Table 5. The surface energy increases from about 40 to over 70mJ/m2, depending on the plasma conditions. For these samples, thin glass sheets were bonded individually. After testing at a temperature of 600°C, the thin glass sheets of all samples were easily debonded by hand.

Example of simultaneous N2 and H2 plasma treatment (5m).

Moderate surface energy SML (comparative example 5g) was deposited in an ICP plasma system from 30sccm CF4 10sccm C4F8 20sccm H2 at 5mT with 1000W coil and 50W platen RF power. The surface tension of the untreated fluoropolymer membranes is shown in Table 5. Sample 5m was treated in situ with simultaneous N2+H2 plasma in the ICP system under the conditions listed in Table 5. The surface energy did not appear to be different from the untreated fluoropolymer membrane.

Example (5b) of sequential N2 and H2 plasma treatment.

Moderate surface energy SML was deposited in an ICP plasma system from 30sccm CF4 10sccm C4F8 20sccm H2 at 5mT with 1500W coil and 50W platen RF power (comparative example 5a). The surface energy of the untreated fluoropolymer is shown in Table 5. Then the sample was subjected to N2 and H2 plasma in-situ treatment sequentially in the ICP system under the conditions listed in Table 5. The surface energy increases to over 70mJ/m2. This value is similar to that obtained with ammonia or nitrogen plasma. A thin glass sheet was bonded to the sample and subjected to a 600°C temperature test, after which the thin glass sheet could be debonded from the carrier, ie the sample passed part (c) of the 600°C processing test.

XPS data showing the effect of ammonia and nitrogen plasma treatment on the surface modification layer. Specifically, the ammonia plasma treatment roughly halved the carbon content of the surface modification and resulted in a reduction of fluorine concentration by about 1/4 and an increase of nitrogen by about 0.4 at%. Silicon, oxygen, and other glass components were also seen to increase, consistent with ammonia plasma removal of fluoropolymers while adding small amounts of nitrogen species to the surface. Nitrogen plasma treatment increased the nitrogen content to 2 at%, but also decreased the carbon and fluorine content, similar to ammonia. Silicon, oxygen, and other glass components also increase, consistent with a decrease in film thickness. Thus, it was shown that ammonia and nitrogen plasma treatment increased the polar groups of the surface modification layer, but also decreased the thickness of the surface layer. The thickness of the resulting surface modified layer is typically less than 20 nm. Thus, an effective surface modification layer typically balances surface modification layer thickness and thus surface treatment time to achieve controlled bonding.

As mentioned above, the thin glass sheets bonded to the carrier according to the examples in Table 5 were made of The substrates were made of glass (aluminoborosilicate alkali-free glass, available from Corning Incorporated, Corning, NY) and were 100, 130, and 150 microns thick. Clean with SC1 and/or SC2 chemistry and standard cleaning techniques after oxygen plasma prior to bonding Glass.

In the examples of Table 5, although the bonding surface on which the surface modifying layer is disposed is glass, this is not necessarily the case. Rather, the bonding surface may be other suitable materials having similar surface energies and properties to glass, eg silicon, polysilicon, single crystal silicon, ceramic, glass-ceramic, sapphire or quartz.

In the examples in Tables 3 and 5, the use of a plasma polymerized fluoropolymer surface modification layer (thickness less than 20 nm) to control the bonding energy of glass bonding surfaces is demonstrated. The initial bonding of a glass flake to such a glass support with a surface-modified layer on it is similar to a glass-glass bond: the bonding front moves quickly due to the strong attractive interaction between the flake and the coated glass support caused by. The physical cause of this attractive interaction is the dipole-dipole (kissan ) interactions, with or without hydrogen-bonded molecular water. However, the fluoropolymer surface modification prevents permanent adhesion of the flake to the support at temperatures as high as 600°C associated with device fabrication. To offer an attractive cost advantage for low-yield acid thinning of thicker glasses, the support needs to be reusable. This is a consideration when using fluorinated surface modification layers because the fluoropolymer deposition process etches the support surface. While support reuse was demonstrated for these surface modified layers, the surface roughness increased from 0.3 nm to about 1.2 nm Ra. This increase in roughness affects support reusability due to the restricted bond area (on a support that is reused after depositing, removing and re-depositing the surface modifying layer) thereby reducing bond energy. In addition, increased surface roughness can limit the reuse of the carrier for other applications, such as using the carrier itself as a display substrate, because it does not meet the roughness specifications of the input glass. It was also observed that roughness was induced on the bonded surface side of the thin glass sheets after annealing the bonded thin glass sheets and carrier pairs at temperatures >300°C. The increased roughness on the flake bonding surface may be due to the etching of the thin glass bonding surface by desorption of fluorine-containing gas from the surface modifying layer treated carrier bonding surface. In some cases, the increased roughness of the bonding surface is not important. In other cases, although the increase in roughness is small, the increase may be unacceptable, for example, because it may limit the re-use of the carrier. Furthermore, the use of fluorinated gases in certain manufacturing operations is undesirable for reasons such as health and safety.

Thus, there may be situations where it is desirable to use alternative polar bonds to generate sufficient surface energy (e.g., >50 mJ/m2 as described above in connection with the examples in Table ⁵ ) to produce controlled bonding, i.e., Robust enough to withstand FPD processing, but to enable separation of the flakes from the carrier without damage (even after high temperature processing, such as processing above 400°C or 600°C). Therefore, the inventors of the present invention have developed alternative ways to form suitable polar bonds that can be used for controlled bonding of flakes to supports.

The inventors of the present invention have developed the use of hydrocarbon polymers, or more generally, carbonaceous layers, so that little or no fluorine will etch the glass. However, several key challenges need to be overcome. The surface energy of the carbonaceous layer should be greater than about 50 mJ/m ² such that the carbonaceous layer bonds to the glass. In order to provide a bond strong enough to withstand wet processing without liquid penetration between the flake and support, in some cases the surface energy of the carbonaceous surface modification layer should be greater than or equal to 65 mJ/m2. At 65 mJ/m2, the surface energy of the support (for bonding to the thin glass sheet) is sufficient to prevent the penetration of liquid (eg water) between the support and the sheet during subsequent processing. For a surface energy of about 50 mJ/m2, bonding to thin glass sheets may be sufficient for most FPD processing, but heat treatment may be required to prevent liquid penetration. Specifically, the polar component of the hydrocarbon layer needs to increase orderly to achieve strong dipole-to-dipole bonding directly to the silanol groups of the thin glass sheet or mediated by hydrogen-bonded molecular water. The carbonaceous layer should also exhibit thermal, chemical and vacuum compatibility so as to be useful for carrier-sheet articles that will at least withstand the manufacturing process of amorphous silicon (aSi) TFT, color filter (CF) or capacitive touch devices. This appears to be possible since aliphatic hydrocarbons such as polyethylene exhibit excellent thermal stability in an inert atmosphere. Unlike fluoropolymers, which can depolymerize under certain circumstances, HDPE simply chars. Even though HDPE may burn, it is still possible to see through the polymer if the thickness of the polymer is low enough. A final consideration is that mechanical stability and wet processing compatibility appear to require higher adhesion than is achieved by van der Waals forces alone. A bond energy of about 250-275 mJ/m2 was found to be favorable for the glass flakes used to withstand wet ultrasonic processing. This large bond energy may be due to particles and edge defects rather than a fundamental requirement of the bonding process. Optimal bonding of two clean glass surfaces yields a bond energy of approximately 150 mJ/m2. Partial covalent bonding is required to achieve a bond strength of 250-275 mJ/m2.

The surface modification layers developed in the examples in Tables 6-12 are based on the organic case of fluorine-free source materials. As detailed further below, amorphous hydrocarbon layers (or, simply, carbonaceous layers) could be produced on glass supports (Table 6), but the surface energy did not yield sufficient adhesion to clean glass surfaces to withstand FPD processing. This is not surprising since the organic surface modification layer based on methane and hydrogen does not contain strong polar groups. To increase the polar groups available for bonding with thin glass sheets, additional gas was added during plasma polymerization and sufficient surface energy could be achieved (Table 7). However, while sufficient surface energy can be achieved in some cases, this single-step process involves a certain amount of complexity to obtain proper mixing of the source materials. Therefore, a two-step process was developed, wherein: in a first step, a surface-modified layer was formed (e.g., from two gases, in a manner similar to that done in the examples of Table 6); then, in a second step , treating the surface modification layer in various ways to increase the surface energy and polar groups available for bonding to thin glass sheets. Although there are more steps, the process is less complex to manage to achieve the desired result. The treatment increases the polar groups at the surface where the surface modification layer will bond to the flakes. Thus, the polar groups can be used to bond the carbonaceous layer to the flakes, even though in some cases the bulk of the surface-modified layer may not contain polar groups. Various ways of treating the initial surface modification layer were developed in the examples of tables 8-12, wherein: in the example of table 8, the surface modification layer was treated with NH3; in the example of table 9, Use N2 to process the surface modification layer; in the embodiments of Table 10, use N2 and then H2 to process the surface modification layer; in the embodiments of Table 11, use N2-O2 and then use N2 to process the surface modification layer; In the example in Table 12, the surface modification layer was treated with N2-O2; and in the alternate example following Table 12, the surface modification layer was treated with O2 only. These examples show the use of nitrogen and oxygen polar groups, but other polar groups are also possible.

Forming a carbonaceous surface modification layer with a hydrocarbon (e.g., methane CH4) and optionally hydrogen (e.g., H2)

Another example of the use of plasma polymerized films to modulate the surface energy of the bonding surface as well as capping surface hydroxyl groups on the bonding surface is from a carbon-containing gas (e.g., a hydrocarbon gas such as methane) optionally mixed with Together with other gases (eg, hydrogen H2), to deposit the surface modification layer film. In most cases though, hydrogen flow is preferred because otherwise the deposited material tends to be graphitic, dark and has a low bandgap. This is the same for all carbonaceous surface modification layer examples in Tables 6-12 and 16. Surface modification layers can be formed at atmospheric or reduced pressure using plasma excitation such as DC or RF parallel plate, inductively coupled plasma (ICP), electron cyclotron resonance (ECR), downstream microwave or RF plasma. The plasma polymerized surface modification layer can be arranged on the support and/or the foil. As described above with respect to the examples in Table 3, plasma polymerization produced layers of highly cross-linked material. Control of reaction conditions and source gases can be used to control the film thickness, density, and chemical properties of the surface modification layer to tune the functional groups to desired applications, and by controlling the film properties, the surface energy of the bonding surface can be tuned. The surface energy can be tuned to control the degree of bonding, ie to prevent permanent covalent bonding between the flakes and the support during subsequent processing to place films or structures on the flakes.

In the examples in Table 6 below, various conditions were used to deposit plasma polymerized films on glass supports. The deposition parameters explored in the examples of Table 6 were: gas ratio (methane:hydrogen); pressure; ICP coil and RF bias power. The glass carrier is made of (Aluminoborosilicate alkali-free display glass available from Corning Incorporated, Corning NY) Substrates manufactured. Prior to film deposition, clean the support using SC1 and/or SC2 chemistry and standard cleaning techniques. Films were deposited in an Oxford Plasmalab 380 ICP (Inductively Coupled Plasma (ICP) tool) (available from Oxford Instruments, Oxfordshire UK) where the carrier was on a platen to which a specific wattage ( RF energy at 13.56 MHz (recorded in the "RF Bias" column) and a coil placed above the platen to which was applied 13.5 MHz RF energy at a specified wattage (recorded in the "Coil" column). The flow rates of the methane (CH4) and hydrogen (H2) sources into the chamber are shown in the CH4 and H2 columns, respectively (flow rates are standard cubic centimeters per minute, sccm). CH4 and H2 gases flow together. Also shown is the H2:CH4 source gas ratio in the "H2/CH4" column, and the chamber pressure (in mTorr) in the "Pressure" column. Thus, for example, the symbols in Table 6 for Example 6a are read as follows: In an Oxford ICP apparatus, 6.7 sccm of CH4, and 33.3 sccm of H2, flow together into a chamber at a pressure of 20 mTorr; 1500 W of 13.5 MHz RF Power was applied to the coil, and 300W of 13.56 MHz RF power was applied to the platen on which the carrier was placed. For all depositions, the platen temperature was 30C. The symbols of the remaining embodiments can be interpreted in a similar manner. By using the Wu model with three different test liquids (in this case, deionized water (shown in column "W"), hexadecane (shown in column "H"), and diiodomethane (shown in The calculation of the contact angle (CA) in the DIM" column) gives the surface energy in mJ/m ² (millijoules per square meter). For surface energy, the polar (P) and dispersive (D) components and the sum (T) are shown.

The surface energies of Examples 6a-6j varied from about 40 to about 50 mJ/ ^m2 . In general, however, the surface energies of these embodiments are less than about 50 mJ/ ^m2 (considered suitable for controlled bonding of the glass support to the glass flake). The thickness of the surface modification layer is about 6 nm. These examples did not produce sufficient adhesion between the carrier and the thin glass sheet to survive FPD processing, i.e., their blistering was observed during vacuum testing, and hot water penetration was observed during wet processing testing .

Although these surface modification layers themselves are not suitable for bonding to thin glass sheets, they can be used in other applications, for example, the application of polymer sheets to glass supports for the fabrication of electronics or other structures on thin polymer sheets, as follows described in the text. Alternatively, the sheet may be a composite sheet having a polymer surface bondable to a glass carrier. In this case, the composite sheet may comprise a glass layer on which electronics or other structures may be disposed, while the polymer portion forms the bonding surface for controlled bonding to the glass carrier.

In the examples of Table 6, although the bonding surface on which the surface modifying layer is disposed is glass, this is not necessarily the case. Rather, the bonding surface may be other suitable materials having similar surface energies and properties to glass, eg silicon, polysilicon, single crystal silicon, ceramic, glass-ceramic, sapphire or quartz.

Single-step formation of surface-modified layers with mixtures of non-fluorinated sources

Another example of the use of plasma-polymerized films to modulate the surface energy of the bonding surface and capping surface hydroxyl groups on the bonding surface is the deposition of surface modifications from a mixture of non-fluorinated gas sources, including carbonaceous gases, e.g., hydrocarbons. layer film. Deposition of surface modification layers can be performed at atmospheric or reduced pressure using plasma excitation such as DC or RF parallel plate, inductively coupled plasma (ICP), electron cyclotron resonance (ECR), downstream microwave or RF plasma. The plasma polymerized surface modification layer can be arranged on the support and/or the foil. As described above with respect to the examples in Table 3, plasma polymerization produced layers of highly cross-linked material. Control of reaction conditions and source gases can be used to control the film thickness, density, and chemical properties of the surface modification layer to tune the functional groups to desired applications, and by controlling the film properties, the surface energy of the bonding surface can be tuned. The surface energy can be tuned to control the degree of bonding, ie to prevent permanent covalent bonding between the flakes and the support during subsequent processing to place films or structures on the flakes.

In the examples in Table 7 below, various conditions were used to deposit plasma polymerized films on glass supports. The glass carrier is made of (Aluminoborosilicate alkali-free display glass available from Corning Incorporated, Corning NY) Substrates manufactured. Prior to film deposition, clean the support using SC1 and/or SC2 chemistry and standard cleaning techniques. Films were deposited in an Oxford Plasmalab 380 ICP (inductively coupled plasma (ICP) configuration mode) (available from Oxford Instruments, Oxfordshire UK), where the carrier was on a platen to which a specific wattage was applied ( RF energy at 13.56 MHz (recorded in the "RF Bias" column) and a coil placed above the platen to which was applied 13.5 MHz RF energy at a specified wattage (recorded in the "Coil" column). The flow rates of methane (CH4), nitrogen (N2) and hydrogen (H2) source gases into the chamber are shown in the CH4, N2 and H2 columns, respectively (flow rates are standard cubic centimeters per minute, sccm). CH4, N2 and H2 gases flow together. Also shown is the N2:CH4 source gas ratio in the "N2:CH4" column, and the chamber pressure (in mTorr) in the "Pressure" column. Thus, for example, the symbols in Table 7 for Example 7g are read as follows: In an Oxford 380 ICP apparatus, 15.4 sccm of CH, 3.8 sccm of N, and 30.8 sccm of H flow together into a chamber at a pressure of 5 millitorr; 1500 W of 13.5 MHz RF power was applied to the showerhead, and 50 W of 13.56 MHz RF power was applied to the platen on which the carrier was placed. For all samples in Table 7, the platen temperature was 30C. The symbols of the remaining embodiments can be interpreted in a similar manner. By using the Wu model with three different test liquids (in this case, deionized water (shown in column "W"), hexadecane (shown in column "H"), and diiodomethane (shown in The calculation of the contact angle (CA) in the DIM" column) gives the surface energy in mJ/m ² (millijoules per square meter). For surface energy, the polar (P) and dispersive (D) components and the sum (T) are shown. Additionally, in the "Thickness" column, the thickness value (in Angstroms) of the surface modification layer deposited under the conditions reported for that particular example is shown.

Example 7a shows a surface modified layer made from methane only. Under these deposition conditions, the methane-formed surface-modified layer achieved a surface energy of only about 44 mJ/m2 ^on the support. While this is not a desired level for controlled glass-to-glass bonding, it can be used to bond a polymer bonding surface to a glass support.

Examples 7b-7e show surface modification layers produced by plasma polymerization of methane and nitrogen at various N2:CH4 ratios. Under these deposition conditions, the methane-nitrogen formed surface modified layer achieved a surface energy on the support of about 61 mJ/m ² (Example 7e) to about 64 mJ/m ² (Example 7d). These surface energies are sufficient for the controlled bonding of thin glass sheets to glass supports.

Example 7f shows a surface modification layer produced by plasma polymerization of methane and hydrogen (H2). Under these deposition conditions, the surface-modified layer formed by methane-hydrogen gas achieved a surface energy of about 60 mJ/m2 ^on the support, which is sufficient for the controlled bonding of thin glass flakes to the glass support.

Examples 7g-7j show surface modification layers produced by plasma polymerization of methane, nitrogen and hydrogen. Under these deposition conditions, the surface modification layer formed by methane-nitrogen-hydrogen achieved a surface energy on the support of about 58 mJ/m ² (Example 7g) to about 67 mJ/m ² (Example 7j), which is It is sufficient for controlled bonding of thin glass sheets to glass supports.

It was observed that for the surface modified layer bonded thin glass and support formed according to Examples 7b-7j, no permanent adhesion occurred after annealing at 450°C, ie they passed part (c) of the 400°C temperature test. Debonding enables the removal of devices fabricated on thin glass and the re-use of the carrier.

The thin glass sheets bonded to the respective supports according to the examples (7b-7j) of Table 7 were made of The substrates were made of glass (aluminoborosilicate alkali-free glass, available from Corning Incorporated, Corning, NY) and were 100, 130, and 150 microns thick. Clean with SC1 and/or SC2 chemistry and standard cleaning techniques after oxygen plasma prior to bonding Glass.

In the examples of Table 7, although the bonding surface on which the surface modifying layer is disposed is glass, this is not necessarily the case. Rather, the bonding surface may be other suitable materials having similar surface energies and properties to glass, eg silicon, polysilicon, single crystal silicon, ceramic, glass-ceramic, sapphire or quartz.

The surface modification layers of the examples of Table 7 were formed by a single-step process. That is, the proper surface energy and inclusion of polar groups is achieved by depositing a surface modification layer under suitable conditions from a selected gas mixture. While achieving the right gas and conditions, the process involves a certain amount of complexity to make the right gas mixture. Therefore, a simpler process is sought. It is assumed that suitable surface energy and suitable polar groups can be achieved from a two-step process, where each step would be simple and robust. Specifically, it is assumed that in the first step, a carbonaceous surface modification layer is deposited, while in the second step, the surface modification layer is treated to increase the surface energy and establish a suitable pole for controlled bonding. Polar groups, where the polar groups may be more concentrated at the surface where the surface modification layer will bond to the flake than they are in the bulk material. From the examples in Table 6 it was found that pressure and coil power had the greatest impact on surface energy. In addition, it was also found that the film thickness appeared to increase with increasing bias and decreasing pressure. Therefore, from these results, chosen as a starting point to further investigate treatments to increase surface energy and bind polar groups, the amorphous hydrocarbon polymer surface modification layer deposition process was 20sccm CH4 40sccmH2 5mT 1500/50W 60s, which yielded a thickness of A carbonaceous surface modification layer of approximately 6.5 nm. For the surface modification layer of the substrate, various treatments are carried out in the second step, as shown in the examples of Tables 8-11, in order to improve the polar groups and their concentration at the surface of the surface modification layer of the sheets to be bonded. modified. Although specific examples of starting and processing materials for the surface-modifying layer are discussed below, generally, the carbonaceous layer is formed from a carbon-containing source and then polar groups are added by subsequent processing. Similarly, although specific polar groups are shown in the examples, others are possible.

Introduce polar groups to the carbonaceous surface modification layer by NH3 treatment

Another example of using plasma polymerized films to tune the surface energy of bonding surfaces and create alternative polar bonding sites on them is the deposition of surfaces from carbon sources (e.g. methane, a source of carbon-containing gases) and from hydrogen (H2) The modified layer film is then treated with nitrogen on the newly formed surface modified layer. Nitrogen treatment can be performed with, for example, ammonia plasma treatment. Deposition of surface modification layers can be performed at atmospheric or reduced pressure using plasma excitation such as DC or RF parallel plate, inductively coupled plasma (ICP), electron cyclotron resonance (ECR), downstream microwave or RF plasma. The plasma polymerized surface modification layer can be arranged on the support and/or the foil. As described above with respect to the examples in Table 3, plasma polymerization produced layers of highly cross-linked material. Control of reaction conditions and source gases can be used to control film thickness, density, and chemistry to tune functional groups to desired applications, and by controlling film properties, the surface energy of the bonding surface can be tuned. Nitrogen-based polar groups formed during subsequent ammonia plasma treatment do not condense with silanols to cause permanent covalent bonding; thus enabling control of the wafer during subsequent processing to place films or structures on the wafer degree of adhesion to the carrier.

In the examples in Table 8 below, various conditions were used to deposit plasma polymerized surface modified layer films on glass supports. The glass carrier is made of (Aluminoborosilicate alkali-free display glass available from Corning Incorporated, Corning NY) Substrates manufactured. Prior to film deposition, clean the support using SC1 and/or SC2 chemistry and standard cleaning techniques. The surface treatment was deposited in an Oxford Plasmalab 380 ICP (inductively coupled plasma (ICP) configuration mode) (obtained from Oxford Instruments, Oxfordshire UK) where the carrier was on a platen to which a specific wattage was applied The 13.56MHz RF energy, the coil is arranged above the platen, and the 13.5MHz RF energy of a specific wattage is applied to it. For applied power, more typically, the quantity is shown as #/#W, where the number before the slash is the wattage applied to the coil (sprinkler) and the number after the slash is the wattage applied to the platen number. When only one number is displayed, this is the number of the coil. The gas flow rates into the chamber are shown in Table 8 (flow rates are standard cubic centimeters per minute, sccm). In the plasma treatment of the surface modification layer (SML), the chamber temperature was 30°C. Thus, for example, the symbols in the "Surface Treatment" column of Table 8 for Example 8a are read as follows: In an Oxford ICP apparatus, 40 sccm of CH was flowed into the chamber at a pressure of 5 mTorr; 1500 W of RF energy at 13.5 MHz was applied to the showerhead; 50 W of 13.56 MHz RF energy was applied to the platen on which the carrier was placed; the chamber temperature was 30° C.; and the deposition time was 60 seconds. The symbols in the surface treatment column of the remaining examples can be read in a similar manner, except that the surface treatment was carried out in STSMultiplex PECVD (available from SPTS, Newport, UK). The carrier on a grounded electrode was maintained at 200C and gas was introduced into the showerhead driven by 13.56MHz RF. For another example, in the "plasma treatment" column, the symbols for the treatment of embodiment 8a are interpreted as follows: after the surface modification layer is formed according to the parameters of the surface treatment column of embodiment 8a, then 100 sccm of NH is supplied to the chamber, The pressure of the chamber was 1 Torr, and the temperature was 200° C.; 300 W of 13.56 MHz was applied to the shower head; and the treatment was carried out for 60 seconds. The symbols in the "plasma treatment" column of the remaining examples are interpreted in a similar manner. The surface energy in mJ/ ^m2 ( millijoules per square meter). For surface energy, the polar (P) and dispersive (D) components and the sum (T) are shown.

Examples 8a and 8b show plasma polymerized hydrocarbon surface modification layers with subsequent treatment with nitrogen containing gas (ammonia). In the case of Example 8a the ammonia itself was used at a power of 300W, while in Example 8b the ammonia was diluted with helium and polymerized at a lower power of 50W. In each case, however, sufficient surface energy was achieved on the carrier bonding surface to allow its controllable bonding to the thin glass sheet. Examples 8c and 8d show plasma polymerized hydrocarbon surface modification layers formed by hydrocarbon containing (methane) and hydrogen containing (H2) gas followed by subsequent treatment with nitrogen containing gas (ammonia). In the case of Example 8c the ammonia itself was used at a power of 300W, whereas in Example 8d the ammonia was diluted with helium and the polymerization was carried out at a lower power of 50W. It was observed that for the surface modified layer bonded thin glass and support formed according to Examples 8a-8d, no permanent adhesion occurred after annealing at 450°C, ie they were able to pass part (c) of the 400°C temperature test. No degassing test was performed on these samples. Furthermore, these examples are robust enough to withstand FPD processing (including the vacuum test (1), wet processing test (2) and ultrasonic test (5) described above), and are still achievable by applying sufficient peel force. disbonded. Debonding enables the removal of devices fabricated on thin glass and the re-use of the carrier.

The thin glass sheets bonded to the respective carriers according to the examples in Table 8 were made of The substrates were made of glass (aluminoborosilicate alkali-free glass, available from Corning Incorporated, Corning, NY) and were 100, 130, and 150 microns thick. Clean with SC1 and/or SC2 chemistry and standard cleaning techniques after oxygen plasma prior to bonding Glass.

In the examples of Table 8, although the bonding surface on which the surface modifying layer is disposed is glass, this is not necessarily the case. Rather, the bonding surface may be other suitable materials having similar surface energies and properties to glass, eg silicon, polysilicon, single crystal silicon, ceramic, glass-ceramic, sapphire or quartz.

Introduce polar groups to the carbonaceous surface modification layer by N2 treatment

Another example of the use of plasma-polymerized films to tune the surface energy of bonding surfaces and create alternative polar bonding sites on them is the deposition of surface modifications from carbon sources such as carbon-containing gases such as methane and from hydrogen H2 deposition. layer of thin film, and then nitrogen treatment of the newly formed surface modification layer. In order to form nitrogen-based polar groups on the surface modification layer, nitrogen treatment may be performed by plasma treatment of N2 gas. Deposition of surface modification layers can be performed at atmospheric or reduced pressure using plasma excitation such as DC or RF parallel plate, inductively coupled plasma (ICP), electron cyclotron resonance (ECR), downstream microwave or RF plasma. The plasma polymerized surface modification layer can be arranged on the support and/or the foil. As described above with respect to the examples in Table 3, plasma polymerization produced layers of highly cross-linked material. Control of reaction conditions and source gases can be used to control the film thickness, density, and chemical properties of the surface modification layer to tune the functional groups to desired applications, and by controlling the film properties, the surface energy of the bonding surface can be tuned. Nitrogen-based polar groups formed during subsequent plasma processing do not condense with silanols to cause permanent covalent bonding; thus enabling control of the relationship between the flake and the flake during subsequent processing to place films or structures on the flake. The degree of bonding between the supports.

In the examples in Table 9 below, plasma polymerized films deposited on glass supports were subjected to nitrogen treatment using various conditions. The glass carrier is made of (Aluminoborosilicate alkali-free display glass available from Corning Incorporated, Corning NY) Substrates manufactured. Prior to surface modification layer deposition, the support is cleaned using SC1 and/or SC2 chemistry and standard cleaning techniques. The surface modification layer was deposited in an Oxford Plasmalab 380 ICP (inductively coupled plasma (ICP) configuration mode) (obtained from Oxford Instruments, Oxfordshire UK), where the carrier was on a platen to which 50W energy at 13.56MHz, a coil is arranged above the platen, and 50W RF energy at 13.5MHz is applied to it. 20 seem of methane (CH4) and 40 seem of hydrogen (H2) flowed into the chamber at a pressure of 5 mTorr. For all samples listed in Table 9, the surface treatment time was 60 seconds and the platen temperature was 30C. After the foregoing deposition, the surface modification layer was treated with nitrogen. Specifically, during processing, a specific wattage (recorded in the "RF Bias" column) of 13.56 MHz RF energy was applied to the platen, a coil was placed over the platen, and a specific wattage (recorded in the "RF Bias" column) was applied to it. 13.5MHz RF energy. N2 flows into the chamber at a rate of 40 sccm, and the duration is listed in the table (unit, second, s). Thus, for example, the symbols for the nitrogen treatment of Table 9 for Example 9a are read as follows: In the Oxford ICP apparatus, 40 sccm of N was flowed into the chamber at a pressure of 5 mTorr; 1500 W of RF energy at 13.5 MHz was applied to the showerhead; and 300 W of RF energy at 13.56 MHz was applied to the platen on which the carrier was placed; the temperature control was 30° C.; and the processing time was 10 seconds. The symbols of the remaining embodiments can be interpreted in a similar manner. By using the Wu model with three different test liquids (in this case, deionized water (shown in column "W"), hexadecane (shown in column "HD"), and diiodomethane (shown in column " The calculation of the contact angle (CA) in the DIM" column) gives the surface energy in mJ/m ² (millijoules per square meter). For surface energy, the polar (P) and dispersive (D) components and the sum (T) are shown.

Examples 9a-9j show various conditions that can be used for nitrogen treatment of methane/hydrogen formed surface modification layers, whereby various surface energies can be obtained, i.e. from about 53 ^mJ /m (Example 9i) to about 63 mJ/m m ² (Example 9b), which is suitable for bonding to thin glass sheets. These surface energies obtained after nitrogen treatment increased from about 42 mJ/m ² (obtained for substrate layers formed by methane-hydrogen plasma polymerization). It was observed that for the surface modified layer bonded thin glass and support formed according to Examples 9a-9j, no permanent adhesion occurred after annealing at 450°C, ie they passed part (c) of the 400°C temperature test. No degassing test was performed on these samples. Furthermore, these examples are robust enough to withstand FPD processing (including the vacuum test (1), wet processing test (2) and ultrasonic test (5) described above), and are still achievable by applying sufficient peel force. disbonded. Debonding enables the removal of devices fabricated on thin glass and the re-use of the carrier.

The thin glass sheets bonded to the respective carriers according to the examples in Table 9 were made of The substrates were made of glass (aluminoborosilicate alkali-free glass, available from Corning Incorporated, Corning, NY) and were 100, 130, and 150 microns thick. Clean with SC1 and/or SC2 chemistry and standard cleaning techniques after oxygen plasma prior to bonding Glass.

In the examples of Table 9, although the bonding surface on which the surface modifying layer is disposed is glass, this is not necessarily the case. Rather, the bonding surface may be other suitable materials having similar surface energies and properties to glass, eg silicon, polysilicon, single crystal silicon, ceramic, glass-ceramic, sapphire or quartz.

Introduce polar groups to the carbonaceous surface modification layer by sequential N2 treatment followed by H2 treatment

Another example of using plasma polymerized films to tune the surface energy of bonding surfaces and create alternative polar bonding sites on them is the deposition of surfaces from carbon sources (e.g. methane, a source of carbon-containing gases) and from hydrogen (H2) Modified layer thin film, then nitrogen treatment and then hydrogen treatment are performed on the surface modification layer just formed. Deposition of surface modification layers can be performed at atmospheric or reduced pressure using plasma excitation such as DC or RF parallel plate, inductively coupled plasma (ICP), electron cyclotron resonance (ECR), downstream microwave or RF plasma. The plasma polymerized surface modification layer can be arranged on the support and/or the foil. As described above with respect to the examples in Table 3, plasma polymerization produced layers of highly cross-linked material. Control of reaction conditions and source gases can be used to control the film thickness, density, and chemical properties of the surface modification layer to tune the functional groups to desired applications, and by controlling the film properties, the surface energy of the bonding surface can be tuned. Nitrogen-based polar groups formed during subsequent plasma processing do not condense with silanols to cause permanent covalent bonding; thus enabling control of the relationship between the flake and the flake during subsequent processing to place films or structures on the flake. The degree of bonding between the supports.

In the examples in Table 10 below, plasma polymerized films deposited on glass supports were treated (nitrogen treatment followed by hydrogen treatment) using various conditions. The glass carrier is made of (Aluminoborosilicate alkali-free display glass, available from Corning Incorporated, Corning NY) Substrates. Prior to film deposition, clean the support using SC1 and/or SC2 chemistry and standard cleaning techniques. Films were deposited in an Oxford Plasmalab 380 ICP (inductively coupled plasma (ICP) configuration mode) (available from Oxford Instruments, Oxfordshire UK) with the carrier on a platen to which 50 W at 13.56 MHz was applied A coil is arranged above the platen, and 50W RF energy of 13.5MHz is applied to it. 20 seem of methane (CH4) and 40 seem of hydrogen (H2) flowed into the chamber at a pressure of 5 mTorr. For all samples listed in Table 9, the surface treatment time was 60 seconds and the platen temperature was 30C. After the foregoing deposition, the surface modification layer is treated sequentially with nitrogen and then hydrogen. Specifically, in each case, for nitrogen treatment: 40 sccm of N was flowed into the chamber to which 1500 W of 13.5 MHz RF energy was applied; the chamber pressure was 5 mTorr; 50 W of 13.56 MHz RF energy was applied to the platen; And the processing is performed for 60 seconds. Then, during hydrogen treatment, 13.56 MHz RF energy was applied to the platen at a specified wattage (recorded in the "RF Bias" column of Table 10) and a coil was placed over the platen to apply a specified wattage (recorded in 13.5 MHz RF energy in column "Coil". H2 flows into the chamber at a rate of 40 sccm, and the duration is listed in the table (unit, second, s). Thus, for example, the notation for the hydrogen treatment (after thin film deposition and N2 treatment as described above) of Table 10 for Example 10a is read as follows: 750W of 13.5MHz RF energy was applied to the showerhead; and 50W of 13.56MHz RF energy was applied to the platen on which the carrier was placed; and the processing time was 15 seconds. The symbols of the remaining embodiments can be interpreted in a similar manner. By using the Wu model with three different test liquids (in this case, deionized water (shown in column "W"), hexadecane (shown in column "H"), and diiodomethane (shown in The fit of the contact angle (CA) in the DIM" column)) calculates the surface energy in mJ/m ² (millijoules per square meter). For surface energy, the polar (P) and dispersive (D) components and the sum (T) are shown.

The methane-hydrogen formed plasma polymerized surface modification layer can be sequentially subjected to N2 plasma treatment followed by H2 plasma treatment under various conditions to achieve various surface energies. As can be seen from Table 10, the surface energy varies from about 60 mJ/ ^m2 (Example 10d) to about 64 mJ/ ^m2 (Examples 10a, 10n, 10o and 10p), which is suitable for bonding to thin glass sheets. It was observed that for the surface modified layer bonded thin glass and support formed according to Examples 10a-10p, no permanent adhesion occurred after annealing at 450°C, ie they were able to pass part (c) of the 400°C processing test. Furthermore, these examples are robust enough to withstand FPD processing (including the vacuum test (1), wet processing test (2) and ultrasonic test (5) described above), and are still achievable by applying sufficient peel force. disbonded. Debonding enables the removal of devices fabricated on thin glass and the re-use of the carrier.

The thin glass sheets bonded to the respective carriers according to the examples in Table 10 were made of The substrates were made of glass (aluminoborosilicate alkali-free glass, available from Corning Incorporated, Corning, NY) and were 100, 130, and 150 microns thick. Clean with SC1 and/or SC2 chemistry and standard cleaning techniques after oxygen plasma prior to bonding Glass.

In the examples of Table 10, although the bonding surface on which the surface modifying layer is disposed is glass, this is not necessarily the case. Rather, the bonding surface may be other suitable materials having similar surface energies and properties to glass, eg silicon, polysilicon, single crystal silicon, ceramic, glass-ceramic, sapphire or quartz.

As a variant of the example of Table 10, the surface modification layer formed by methane was also sequentially subjected to nitrogen treatment and then hydrogen treatment. In this case, only methane was used (no hydrogen was used) when the initial surface modification layer was formed on the glass support by plasma polymerization. Specifically, 40 sccm of methane was flowed at 5 mTorr at 1500/50W for 60 seconds. The measured surface energy was about 42 mJ/m ² . After sequentially treating with nitrogen (40 sccm N2, 5 mTorr pressure, 1500/50W power for 15 seconds) and then hydrogen (40 sccm H2, 5 mTorr pressure, 1500/50W power for 15 seconds), the The realized surface energy on the junction surface increases to about 64 mJ/m ² , suitable for bonding thin glass sheets to glass supports.

As mentioned above, sequential N2 and H2 treatment of the carbonaceous surface modification layer achieved a surface energy of about 64 mJ/m2, and formed a bond front velocity slightly lower than that typical for a fluorinated surface modification layer that is compatible with thin Initial Room Temperature Bonding of Glass Sheets. For the examples in Table 10, it was observed that the samples did not adhere permanently after annealing at 450°C, ie they were able to pass part (c) of the 400°C processing test. Furthermore, these examples are robust enough to withstand FPD processing (including the vacuum test (1), wet processing test (2) and ultrasonic test (5) described above), and are still achievable by applying sufficient peel force. disbonded. Debonding enables the removal of devices fabricated on thin glass and the re-use of the carrier.

Introduce polar groups to the carbonaceous surface modification layer by sequential N2-O2 treatment followed by N2 treatment

Based on the idea of trying to generate more polar imide groups on the surface to increase the speed of the bonding front, a sequential N2-O2 and then N2 plasma treatment of the carbonaceous surface modification layer was developed.

In this example of using a plasma-polymerized film to tune the surface energy of the bonding surface and create alternative polar bonding sites thereon, carbon was deposited from a carbon source (such as a carbon-containing gas such as methane) and from hydrogen H2 Surface modification layer thin film, and then N2-O2 and then N2 treatment on the newly formed surface modification layer in sequence. Deposition of surface modification layers can be performed at atmospheric or reduced pressure using plasma excitation such as DC or RF parallel plate, inductively coupled plasma (ICP), electron cyclotron resonance (ECR), downstream microwave or RF plasma. The plasma polymerized surface modification layer can be arranged on the support and/or the foil. As described above with respect to the examples in Table 3, plasma polymerization produced layers of highly cross-linked material. Control of reaction conditions and source gases can be used to control the film thickness, density, and chemical properties of the surface modification layer to tune the functional groups to desired applications, and by controlling the film properties, the surface energy of the bonding surface can be tuned. Nitrogen-based polar groups formed during subsequent plasma processing do not condense with silanols to cause permanent covalent bonding; thus enabling control of the relationship between the flake and the flake during subsequent processing to place films or structures on the flake. The degree of bonding between the supports.

In the examples in Table 11 below, plasma polymerized films deposited on glass supports were treated using various conditions to increase surface energy and bind polar groups. The glass carrier is made of (Aluminoborosilicate alkali-free display glass, available from Corning Incorporated, Corning NY) Substrates. Prior to surface modification layer deposition, the support is cleaned using SC1 and/or SC2 chemistry and standard cleaning techniques.

In step 1, the surface modification layer was deposited in an Oxford Plasmalab 380 ICP (inductively coupled plasma (ICP) configuration mode) (obtained from Oxford Instruments, Oxfordshire, UK) with the carrier on the platen , apply 50W energy of 13.56MHz to it, arrange coils above the platen, apply 50W RF energy of 13.5MHz to it. 20 seem of methane (CH4) and 40 seem of hydrogen (H2) flowed into the chamber at a pressure of 5 mTorr. For all samples listed in Table 11, the surface treatment time was 60 seconds and the platen temperature was 30C.

After the aforementioned deposition in step 1, in step 2, the surface modification layer is treated with nitrogen and oxygen. Specifically, in the process of step 2, 50W of 13.56MHz RF energy is applied to the platen, a coil is arranged above the platen, and 800W of 13.56MHz RF energy is applied thereto. N2 and O2 flow into the chamber at a specific rate (unit, sccm) for the duration listed in the table (unit, second, s). Thus, for example, the symbols for Step 2 of Table 11 for Example 11a are read as follows: After the deposition of the surface modification layer in Step 1, 35 sccm of N was flowed together with 5 sccm of O in the Oxford ICP apparatus at a pressure of 15 mTorr 800W of 13.5MHz RF energy is applied to the shower head; and 50W of 13.56MHz RF energy is applied to the platen on which the carrier is placed; the temperature is controlled at 30° C.; and the treatment is performed for 5 seconds. The symbols of the remaining embodiments can be interpreted in a similar manner.

After the aforementioned step 2 treatment, in step 3, the surface modification layer is treated with nitrogen. Specifically, in the process of step 3, 50W of 13.56MHz RF energy is applied to the platen, a coil is arranged above the platen, and 1500W of 13.56MHz RF energy is applied thereto. N2 flows into the chamber at a specific rate (unit, sccm) for the duration listed in the table (unit, second, s). Thus, for example, the symbols for Step 3 of Table 11 for Example 11a are read as follows: After the deposition of the surface modifying layer in Step 1, and after the nitrogen-oxygen treatment in Step 2, 40 sccm of N2 1500W of 13.5MHz RF energy is applied to the showerhead; and 50W of 13.56MHz RF energy is applied to the platen on which the carrier is placed; the temperature is controlled at 30°C; and the process is carried out 15 seconds. The symbols of the remaining embodiments can be interpreted in a similar manner.

The surface energy in mJ/m ² (millijoules per 2 square meters). For surface energy, the total surface energy (T, which includes both polar and dispersive components) is shown. The unit of bond energy calculation is mJ/m2, as described above. The number of bubbles after initial bonding is shown in the column titled "23C% Area" and the number of bubbles after the 400°C temperature test is shown in the column titled "400C% Area". The number of bubbles is determined by an optical scanner as described below for "degassing". Finally, the change in bubble area from the initial 23°C to 400°C after the temperature test is shown in the column titled "Δ% Area".

Examples 11a-11e show the various conditions that can be used for sequential nitrogen-oxygen treatment of methane/hydrogen formed surface modification layer followed by nitrogen treatment so that various surface energies can be obtained, i.e. about 65 ^mJ /m (Example 11a - 11e) to about 70 mJ/m ² (Examples 11b-11d), which are suitable for bonding to thin glass sheets. These surface energies obtained after sequential nitrogen-oxygen treatment and then nitrogen treatment increase from about 40-50 mJ/m2 ⁽ obtained for substrate layers formed by methane-hydrogen plasma polymerization). It was observed that for the surface modified layer bonded thin glass and support formed according to Examples 11a-11f, no permanent adhesion occurred after annealing at 400°C, ie they passed part (c) of the 400°C temperature test. As shown in Examples 11a-11e, the change in % bubble area that occurs during annealing at 400°C is consistent with no outgassing. On the other hand, for Example 11f, the change in % bubble area that occurs during the 400°C anneal is consistent with partial outgassing of the material in the surface modification layer. Therefore, according to the conditions of Table 11, step 3 is important in order to obtain the deposition of the surface modification layer without degassing. However, under other deposition/processing conditions of steps 1 and 2, step 3 may not be necessary in order to obtain results similar to those obtained in step 3 of Examples 11a-e without degassing. In addition, these examples are robust enough to withstand FPD processing (including the vacuum test (1), wet processing test (2) and ultrasonic test (5) described above), and after the 400°C temperature test, by applying Sufficient peel force is still debondable. Debonding enables the removal of devices fabricated on thin glass and the re-use of the carrier.

Table 11 shows the effect of these sequential steps on surface energy, bond energy and blistering. The increase of oxygen fraction in the N2-O2 step decreased the surface energy as well as increased foaming during the outgassing test. The performance of a brief (approximately 5 seconds) low oxygen fraction (38/2) N2-O2 step followed by a short (15 seconds) N2 plasma treatment (Example 11d) yielded a surface energy of 69 mJ/m2 and a temperature of 400 °C 1.2% bubble area (its % bubble area change at 23°C is -0.01, indicating no outgassing) performance during the temperature test. Samples 11a-e performed comparable to fluorinated surface modification layers when tested at temperatures as high as 400°C.

The thin glass sheets bonded to the respective carriers according to the examples in Table 11 were made of The substrates were made of glass (aluminoborosilicate alkali-free glass, available from Corning Incorporated, Corning, NY) and were 100, 130, and 150 microns thick. Clean with SC1 and/or SC2 chemistry and standard cleaning techniques after oxygen plasma prior to bonding Glass.

In the examples of Table 11, although the bonding surface on which the surface modifying layer is disposed is glass, this is not necessarily the case. Rather, the bonding surface may be other suitable materials having similar surface energies and properties to glass, eg silicon, polysilicon, single crystal silicon, ceramic, glass-ceramic, sapphire or quartz.

The examples described above illustrate how an inductively coupled plasma (ICP) system can be used to deposit thin organic surface modification layers suitable for controlled bonding of thin glass sheets to glass supports for use in devices processing. However, the solution is scalable for display applications where it is advantageous to have a large area substrate. ICP tools employ planar, cylindrical, or hemispherical coils to inductively couple electrical currents to generate time-varying magnetic fields that cause ion circulation. Typically, a second RF source is connected to the platen on which the substrate is placed. The advantage of ICP plasmas is that the ICP source can achieve high levels of ionization independent of the substrate bias controlled by the platen RF source. Current parallel-plate reactive ion etch (RIE) systems cannot achieve such high levels of ionization. Furthermore, bias and ionization are related by RF power and pressure. TEL and others have scaled ICP etchers to Gen 5, but larger scale is challenging to generate a uniform ICP plasma source. On the other hand, RIE mode processing is suitable for parallel plate tools, which has been scaled up to Gen10. Therefore, the inventors of the present invention have developed an implementation in the RIE mode process with results similar to those implemented by the ICP tool, as described above.

Initial attempts to generate surface modification layers in RIE mode from non-fluorinated source materials by simply utilizing Oxford (RIE mode, no coil power) and a bias power of 200 W (equivalent to the case for depositing fluorinated surface modification layers) , yields a dark thick layer that can be modified with nitrogen for bonding thin glass sheets. However, this dark material produced many bubbles covering about 25% of the bonded area after being subjected to the 400°C processing test. The dark deposit characterized by spectral ellipsometry shows a film thickness of about 100 nm and exhibits a much narrower optical band gap, 0.6 eV vs 1.7 eV, for the ICP deposited surface modified layer. From this result it was concluded that the material may be graphitic and increasing the hydrogen content would be a consideration to reduce foaming.

Experiments were performed to capture optical emission spectroscopy (OES) spectra to plot RIE process variables, H2/CH4 ratio, RF power, and pressure. However, in the machining window of the Oxford tool used, these scales could not be matched. However, the experiment did show that the process would benefit from very high hydrogen dilution, high RF power, and low pressure to form polymer gas.

In addition to OES, to guide the process transition from ICP to RIE mode, residual gas analysis (RGA) was used to map the gas phase species present in Oxford versus hydrogen/methane ratio, RF power and pressure in RIE mode. The high line plot of m/e=/16 vs pressure and H2/CH4 gas ratio again shows that high hydrogen dilution is beneficial to match the ICP ratio of about 44. Higher order alkanes are associated with decreased H2/CH4 gas ratio and increased pressure. The contour plots show that m/e = 28/16 increases with increasing RF and H2/CH4 gas ratios. Fitting the RGA response surface suggests that the H2/CH4 and C2H6/CH4 ratios can be matched at 40:1 H2/CH4, 25 mTorr 275W RF. The carbonaceous RIE mode surface modification layer deposited under this condition matches the about 6 nm thickness and 1.6 eV optical bandgap of the ICP mode carbonaceous surface modification layer. Initial trials of nitrogen plasma treatment of carbonaceous RIE surface modified layers also showed low foaming.

Figures 14 and 15 show the kinetics of RIE mode carbonaceous surface modification layer deposition for the process identified using the RGA test. Figure 14 shows the surface energy, including the total surface energy (T) as well as polar (P) and dispersive (D) components. As shown in Figure 14, the surface energy is relatively unchanged, with a slight peak at the 60 second deposition time, while in Figure 15, a nearly linear increase in film thickness on a log-log scale can be seen. This is not a self-limiting process because the etch-back from hydrogen cannot keep up with the polymer deposition.

As noted above, it can be seen from experiments that surface energies > about 50 or > 65 mJ/m2 are beneficial both for initial room temperature bonding and for minimizing bubble area during thermal cycling. From Figure 14 it can be seen that the surface energy is exactly on the boundary line. In some cases, this may be appropriate for bonding the foil and carrier, depending on the time-temperature cycles it will be subjected to, and on other FPD processes it must withstand. On the other hand, however, it may be advantageous to increase the surface energy of the surface modification layer. Any of the sequential treatments described above may be used, for example, ammonia treatment, nitrogen treatment, sequential nitrogen treatment followed by hydrogen treatment, nitrogen-oxygen treatment, sequential nitrogen-oxygen treatment followed by nitrogen treatment. For example, the nitrogen-oxygen treatment will be described in conjunction with Table 12.

Introduction of polar groups into the carbonaceous surface modification layer by nitrogen-oxygen treatment

Another example of using plasma polymerized films to tune the surface energy of bonding surfaces and create alternative polar bonding sites on them is from carbon sources (e.g. methane, carbon-containing gas sources) and from hydrogen (H2 ) depositing a thin film of the surface modification layer, and then performing nitrogen-oxygen treatment on the newly formed surface modification layer. Nitrogen-oxygen treatment may be performed with, for example, nitrogen-oxygen plasma treatment. Deposition of the surface modification layer can be performed at atmospheric or reduced pressure. The plasma polymerized surface modification layer can be arranged on the support and/or the foil. As described above with respect to the examples in Table 3, plasma polymerization produced layers of highly cross-linked material. Control of reaction conditions and source gases can be used to control film thickness, density, and chemistry to tune functional groups to desired applications, and by controlling film properties, the surface energy of the bonding surface can be tuned. Nitrogen-based polar groups formed during subsequent nitrogen-oxygen processing do not condense with silanols to cause permanent covalent bonding; thus enabling control of the flakes during subsequent processing to place films or structures on the flakes degree of adhesion to the carrier.

In the examples in Table 12 below, various conditions were used to deposit plasma polymerized surface modified layer films on glass supports. The glass carrier is made of (Aluminoborosilicate alkali-free display glass available from Corning Incorporated, Corning NY) Substrates manufactured. Prior to film deposition, clean the support using SC1 and/or SC2 chemistry and standard cleaning techniques. The surface modification layer was deposited in an Oxford Plasmalab 380 ICP (in RIE configuration mode) (available from Oxford Instruments, Oxfordshire UK) with the carrier on a platen to which 275 W of RF energy was applied, at The coils are placed above the platen and no energy is applied to them. In step 1, 2 sccm of methane (CH4) and 38 sccm of hydrogen (H2) were flowed into the chamber at a pressure of 25 mTorr. For all samples listed in Table 12, the surface treatment time was 60 seconds and the platen temperature was 30C. After the foregoing deposition, the surface modification layer is treated in step 2 with nitrogen and oxygen. Specifically, during the process of step 2, 13.56 MHz RF energy of a specified wattage (recorded in the "RF" column) was applied to the platen, and the coil was placed above the platen, to which no power was applied. N2 flows into the chamber at the sccm rate listed in the "N2" column, and O2 flows into the chamber at the sccm rate listed in the "O2" column, for the duration (in seconds, s) of the table under "Time (s) " column. The chamber is at pressure in mTorr as listed in the "Pr" column. Thus, for example, the symbols for the nitrogen and oxygen treatments of Step 2 of Table 12 for Example 12b are read as follows: In an Oxford ICP apparatus, 25 sccm of N is flowed together with 25 sccm of O into a chamber at a pressure of 10 mTorr; RF energy at 13.5 MHz was applied to the platen on which the carrier was placed; the temperature control was 30° C.; and the processing time was 10 seconds. The symbols of the remaining embodiments can be interpreted in a similar manner.

The surface energy, in mJ/ m ² (millijoules per square meter). For surface energy, the polar (P) and dispersive (D) components and the sum (T) are shown. Also shown is the thickness of the surface modification layer ("th", in angstroms), the average surface roughness of the support after deposition of the surface modification layer and its N2-O2 treatment ("Ra", in angstroms), Bond energy ("BE", in mJ/m2), and % bubble area change (bubble area after initial bonding of the thin glass sheet to the support via a surface modification layer at room temperature versus heating the support through a 400°C process After the test, between "Δ bubble area)."

The thin glass sheets bonded to the respective carriers according to the examples in Table 12 were made of The substrates were made of glass (aluminoborosilicate alkali-free glass, available from Corning Incorporated, Corning, NY) and were 100, 130, and 150 microns thick. Clean with SC1 and/or SC2 chemistry and standard cleaning techniques after oxygen plasma prior to bonding Glass.

In the examples of Table 12, although the bonding surface on which the surface modifying layer is disposed is glass, this is not necessarily the case. Rather, the bonding surface may be other suitable materials having similar surface energies and properties to glass, eg silicon, polysilicon, single crystal silicon, ceramic, glass-ceramic, sapphire or quartz.

It can be seen from the treatment of the examples in Table 12 that after processing at 400°C: Examples 12a-12j all had a percent bubble area change of less than 2, which is consistent with no degassing at this temperature, see Table 12 for bubbles % column; and likewise, samples 12a, 12b, 12c, 12g, and 12j each have a bonding energy capable of debonding the sheet from the carrier after the temperature test, see column BE of Table 12; however, Examples 12d, 12e, 12f, 12h, and 12i, failed to debond after the 400°C processing test, as indicated by the value of 2500 in the BE column of Table 12.

Surface energy, bubble area, bond energy, and thickness were plotted against % O2, RF, and pressure for the examples according to Table 12 by ellipsometry. Thickness reduction was found to correlate with increasing RF power (Comparative Example 12g and Example 12b), and %O2 was consistent with ashing of the hydrogen layer (Comparative Example 12a and Example 12b). The bonding energy depends only on the pressure: samples treated at 10 mTorr can be debonded after annealing at 400°C (see examples 12a, 12b, 12c, 12g). Those treatments at 35 mTorr and above were not. See, for example, Example 12d processed at 40 mTorr has a bond energy of 2500, and Example 12e has a pressure of 70 mTorr and a bond energy of 2500. A bond energy of 2500 in the "BE" column indicates that the thin glass sheet cannot be debonded from the support. The surface energy of all treated films was 65-72 mJ/m2 independent of thickness. See Examples 12a-12i and 12k. These results indicate that high-pressure N2-O2 plasma treatment produces discontinuous films. In fact, high pressures ablate the membrane rapidly, while lower pressures are advantageous. For foaming, the amount appears to decrease with increasing %O2*RF. In addition, it was found that: H2O partial pressure increases with increasing %O2 and RF; surface modification layer thickness decreases with increasing pressure in step 2, and % bubble area increases with increasing pressure (thus, Lower pressures are advantageous); as the treatment time increases, the thickness of the surface modification layer decreases and the polar groups are reduced, thus resulting in shorter treatment times.

Find the right balance between bonding energy and blistering. The starting point for nitrogen-oxygen treatment was 50% O2, 10 mTorr 300W and varying process times. Three sets of samples were prepared with 20 s, 60 s and 180 s RIE CH4-H2 deposition followed by 0, 5, 15 and 60 s N2-O2 plasma treatment. Both the surface energy and the bond energy peak at 5-15 s N2-O2 plasma treatment time, independent of CH4-H2 deposition time. In 20 seconds the CH4-H2 thin layer is ablated away and the thin glass flake is permanently bonded to the support. The peak occurs before the polymer layer is ablated away, consistent with the formation of polar groups on the polymer film, rather than simply ablation exposing the glass substrate. As the deposition time of the surface modification layer increases, the bubble area does increase, so it is disadvantageous to simply increase the thickness of the surface modification layer to avoid excessive ablation during the subsequent N2-O2 surface treatment. Therefore, a good compromise between adhesion and bubble area is a balance between surface modification layer deposition time and N2-O2 treatment. Depends on the surface modification layer deposition time (not too long, as this would lead to excessive thickness, which leads to increased outgassing) vs. N2-O2 treatment time (not too long to ablate or remove the surface modification layer, which leads to carrier A permanent bond to the flakes, but long enough to allow the polar groups to bind to the surface modification layer) balance. A good compromise is 60 s RIE deposition of the carbonaceous layer followed by a short N2-O2 treatment time of 5-10 s. Examples 12a, 12b, 12c, 12g and 12k work well for RIE mode.

Incorporation of polar groups on the surface modification layer

The mechanism by which N2-O2 plasma treatment produces highly polar surfaces was investigated using XPS N1s species formation. To investigate and confirm the substance formation of these surface-modified layers, studies were conducted in Surface chemistry of thicker films of CH4/H2 deposited on glass wafers such that they achieve full coverage of the glass and subsequent N2/O2 plasma treatment of different durations. An advantage of a thick hydrocarbon film is the ability to distinguish these nitrogen species present only on the hydrocarbon film and separate them from those present on the exposed glass.

The surface composition of glass wafers was first exposed to CH4/H2 plasma for 600 s to deposit a thick hydrocarbon film, followed by 5, 15, 60 and 600 s of N2/O2 plasma. Elements present in the glass (e.g., Al and Ca) were not detected for the 5 and 15 s treatments, suggesting that in those cases the carbonaceous film layer was thicker than the XPS probe depth (approximately 10 nm).

Exposure of the carbonaceous film to N2/O2 plasma for 60 s and 600 s resulted in some thinning of the carbonaceous layer, since in those cases XPS could detect elements present in the glass. This observation is further confirmed by considering the surface concentration of carbon. For the 60 s and 600 s treatments, the C concentrations were less than 10 atomic %, strongly suggesting that the surface is partially covered by a carbonaceous layer for those cases.

NH3+ species were only detected when a significant amount of the carbonaceous layer was etched away. This very strongly suggests that NH3+ species may only be present on the glass, and that other species are involved in the main reaction between the nitrogen and carbonaceous layers. The species formation of nitrogen species is shown in Table 13 below as a percentage of all atoms on the surface (ie, species fraction x detected nitrogen fraction).

It can be seen that the main effect of this N2-O2 treatment is to etch the carbonaceous surface modification layer. In fact, for the 60 and 600 second treatments, very little carbonaceous material was present on the surface. Other observations are that nitrogen species are present on the surface modification layer even after very short N2-O2 treatment times (eg, 5 and 15 seconds). Afterwards, the nitrogen species decreased rapidly while the ammonia species increased rapidly (indicating presence below the glass surface). XPS evaluation of the 5 s N2-O2 plasma treated carbon species for the carbonaceous surface modification layer also revealed the presence of several different species containing oxygen and nitrogen on the surface modification layer. The presence of this oxygen-containing species led to the thinking that O2 plasma alone might be sufficient to impart polar groups to the surface modification layer. In fact, this was found to be the case, as described below.

Based on the assumption that NH3+ species are present only on the glass and not on the carbonaceous layer, the surface coverage can be estimated by calculating the ratio NH3 ⁺ /Σ(all nitrogen compounds). The results of this surface coverage estimate are shown in Figure 17. There is very little variation between 5 seconds and 15 seconds. The largest variation comes between 15 s and 60 s N2-O2 plasma treatment times.

The model for the N2-O2 plasma treatment of the carbonaceous surface modification layer is as follows. CH4-H2 deposition produces continuous hydrocarbon layers. During the first second of N2-O2 plasma treatment, polar -NH2 groups are formed on the polymer surface as the hydrocarbon layer is oxidized and ablated. Imide or amide groups may also have formed at this point, but XPS was inconclusive. By longer N2-O2 plasma treatment, polymer removal reaches the glass surface where polar -NH3+ groups are formed from the interaction of the N2-O2 plasma with the glass surface.

O2 alone as the surface treatment of the surface modification layer

As an alternative to the N2-O2 treatment of carbonaceous layers, the use of O2 alone was also explored to increase the surface energy and generate polar groups on the carbonaceous layers. As mentioned above, 5 s N2-02 plasma treated XPS carbonaceous species of the carbonaceous layer revealed the presence of oxygen-containing species in fact on the surface modified layer. Therefore, O2 treatment of the carbonaceous layer was attempted. O2 treatment was performed in both ICP mode and RIE mode.

In the ICP mode, a base carbonaceous layer was formed following Step 1 in Table 11 above. The surface treatment of step 2 was then performed by flowing 40 sccm O2, 0 sccm N2 at 800/50 W power, 15 mTorr pressure, which produced the desired increase in surface energy, and the desired polar groups on the surface of the carbonaceous layer. At room temperature, the thin glass flakes readily bonded to the surface modification layer. Furthermore, this example observed that no permanent adhesion occurred after annealing at 450°C, ie able to pass part (c) of the 400°C processing test. Furthermore, this embodiment is robust enough to withstand FPD processing (including the vacuum test (1), wet processing test (2) and ultrasonic test (5) described above), and is still achievable by applying sufficient peel force. disbonded. Debonding enables the removal of devices fabricated on thin glass and the re-use of the carrier.

In RIE mode, the base carbonaceous layer was formed following Step 1 in Table 12. The surface treatment of step 2 was then carried out by flowing 50 sccm O2, 0 sccm N2, 200 W power, 50 mTorr pressure. Similar to the ICP mode, these conditions also produce the desired increase in surface energy, and the desired polar groups on the carbonaceous layer. At room temperature, the thin glass flakes readily bonded to the surface modification layer. Furthermore, this example observed that no permanent adhesion occurred after annealing at 450°C, ie able to pass part (c) of the 400°C processing test. Furthermore, this embodiment is robust enough to withstand FPD processing (including the vacuum test (1), wet processing test (2) and ultrasonic test (5) described above), and is still achievable by applying sufficient peel force. disbonded. Debonding enables the removal of devices fabricated on thin glass and the re-use of the carrier.

Therefore, O2 treatment was found to behave similarly to N2-O2 treatment. Similar considerations apply to the balance of initial surface modification layer deposition time (which increases thickness) versus O2 treatment time.

a small amount of fluorine

Several atomic % of F, about 2.2%, was found in the XPS analysis of the hydrocarbon polymer deposited carbonaceous layer in ICP mode. This is in trace amounts and in fact Oxford is used for fluorine and chlorine etching of glass, dielectrics and metals. Small amounts of fluorine were found to be beneficial for the surface modification layer properties of hydrocarbon deposits. A typical reactor cleaning process is SF6-O2 cleaning, followed by O2 cleaning and H2 plasma cleaning. Each step was 30 minutes in length and included pump/purge steps in between. SF6-O2 is used for initial cleaning because the etching rate of hydrocarbon polymers is much higher than that of O2 alone. The H2 plasma cleaning step should have removed most of the deposited mismatch fluorine from the reactor walls. If the H2 plasma cleaning is skipped, a higher amount of fluorine incorporation in the hydrocarbon surface modification layer would be expected. Figure 16 shows the effect of skipping the H2 plasma step for the hydrocarbon surface modification layer. The bond energy drops, displacing the permanent bond until 600°C without a significant increase in blistering. Therefore, small amounts of fluorine in the hydrocarbon surface modification layer, ie, at least up to about 3%, are advantageous.

Surface roughness

The surface roughness changes of the glass bonded surface due to the surface modification layer formed by the deposition of hydrocarbons were investigated. Specifically, a surface modification layer formed of methane-hydrogen followed by nitrogen treatment followed by hydrogen treatment was selected. Two supports were prepared with a surface modification layer formed by methane-hydrogen, followed by in situ N2 plasma treatment followed by H2 plasma treatment (20CH4 40H2 5 mTorr 1500/50W for 60 seconds), then 40N2 5 mTorr 1500/ 50W for 15 seconds, then 40H215 mTorr 1500/50W 15 for 15 seconds). The surface modification layer of the first support (Example 14) was removed by O2 plasma cleaning followed by SC1 cleaning. The surface modification of the second support (Example 14b) was left in place. A third support (Example 14c) was used as reference, to which no surface modification layer had been applied. AFM was used to evaluate the surface roughness of the carrier to which the surface modification layer was applied and then peeled off (Example 14a), the carrier still having the surface modification layer thereon (14b) and the reference carrier (Example 14c). Rq, Ra and Rz from AFM measurements are shown in Table 14 in nm (nanometers). The roughness of Examples 14a and 14b can be distinguished from that of Example 14c. It should be noted that for Example 14c, the excessive z-range in the 5 x 5 micron scan is due to particles in the scan area. Thus, it was seen that the hydrocarbon-formed surface modification layer herein did not alter the surface roughness of the glass bonding surface. In some cases, an unchanged roughness of the bonding surface may be advantageous, for example, for the reuse of the carrier. The glass carriers in these examples are made from (Aluminoborosilicate alkali-free display glass, available from Corning Incorporated, Corning NY) Substrates.

general considerations

The separation of the flakes from the support in Examples 2-12 described above was carried out at room temperature without adding any other thermal or chemical energy to modify the bonding interface between the flakes and the support. The only energy input is mechanical pull and/or peel force.

Since the surface modified layers of Examples 3 and 5-12 are thin organic layers, they are sensitive to oxygen during thermal and plasma processing. Therefore, these surface modification layers should be protected during device fabrication. The surface modification layer should be protected by using an oxygen-free environment (eg, N2 environment) during thermal processing. Alternatively, depositing a protective coating (eg, a thin metal layer) on the interface edge between the bonded thin glass sheet and the support is sufficient to protect the surface modification layer from the oxygen environment at elevated temperature.

When both the sheet and the support include glass bonding surfaces, the surface modifying materials described above in Examples 3-12 can be applied to the support, to the sheet, or both to the support and the substrate that will bond together. flake surface. Alternatively, when one bonding surface is a polymeric bonding surface and the other bonding surface is a glass bonding surface (as further described below), suitable surface modifying materials as described above in Examples 3-12 (based on the surface energy of the polymer bonding surface) will be applied to the glass bonding surface. Furthermore, the entire carrier or sheet need not be made of the same material, but may comprise different layers and/or materials therein, as long as its bonding surface is suitable to receive the surface modification layer of interest. For example, the bonding surface can be glass, glass-ceramic, ceramic, silicon or metal, wherein the rest of the carrier and/or wafer can be of a different material. Additionally, the wafer 20 bonding surface may be any suitable material including, for example, silicon, polycrystalline silicon, single crystal silicon, sapphire, quartz, glass, ceramic, or glass-ceramic. For example, the bonding surface of the carrier 10 may be a glass substrate or other suitable material having a surface energy similar to glass, such as silicon, polysilicon, single crystal silicon, ceramic, glass-ceramic, sapphire or quartz.

As can be seen from the examples described herein, the surface modification layer, together with its subsequent treatment, provides a means of broadly altering the surface energy on the glass bonding surface. For example, for all examples it is seen that the surface energy of the glass bonding surface can vary from about 36 mJ/m2 (eg Example 5g) to about 80 mJ/m2 (Example 5f). Using non-fluorinated source materials in a single-step process without subsequent surface treatment, it was seen that the surface energy of the glass bonding surface could vary from about 37 mJ/m2 (as in Example 16b) to about 67 mJ/m2 (Example 7h and 7j). Using a carbonaceous surface modification layer, with subsequent treatment to add polar groups, it was seen that the surface energy of the glass bonding surface could vary from about 52 mJ/m2 (Example 12j) to about 74 mJ/m2 (Example 8a). Using non-fluorinated source materials in a single-step process or a two-step process, it was seen that the surface energy of the glass bonding surface can vary from about 37 mJ/m2 (Example 16b) to about 74 mJ/m2 (Example 8a). Using fluorine-containing source materials or non-fluorine-containing source materials to deposit surface modification layers, for subsequent processing, it is seen that the surface energy of the glass bonding surface can be changed from about 41 mJ/m2 (Example 5m) to about 80 mJ/m2 ( Example 5f).

Furthermore, as can be seen from the examples herein, the thickness of the surface modification layer can be varied greatly. The desired results were obtained for surface modification layers having a thickness of about 2 nm (as in Example 3) to about 8.8 nm (as in Example 12c).

Uses for Controlled Bonding

reusable carrier

One use of controlled bonding via surface modification layers (comprising materials and associated bonding surface heat treatment) is to provide re-use of supports in articles that have undergone processing requiring temperatures ≥ 600°C (eg, LTPS processing). As illustrated above in Examples 2e, 3a, 3b, 4c, 4d, and 4e, and in Table 5, surface modification layers, including material and bonding surface heat treatments, can be used to provide regeneration of the support under such temperature conditions. use. In particular, these surface modification layers can be used to modify the surface energy of the overlapping region between the bonded regions of the flake (with a glass bonding surface) and the support (with a glass bonding surface), thereby allowing The entire flake is separated from the carrier after processing. The entire wafer can be separated at one time, or the wafer can be separated in sections, for example, first removing the device produced on part of the wafer, and then removing the remaining part to clean the carrier for reuse. In case the entire sheet is removed from the carrier, the carrier can be reused simply by placing another sheet on top of it. Alternatively, the carrier can be cleaned and the carrier flake prepared again by forming the surface modification layer again. Because the surface modification layers prevent permanent bonding of the flakes to the support, they can be used for processing at temperatures ≥ 600 °C. Of course, while these surface modification layers can control the bonding surface energy during processing at temperatures ≥ 600°C, they can also be used to create sheet and support combinations that can withstand processing at lower temperatures and Can be used in such lower temperature applications to control sticking. In addition, when the thermal processing of the product will not exceed 400 ° C, such as the examples of Examples 2c, 2d, 4b, Tables 7-11 (including the examples of alternatives to the examples in Table 10), Example 12a , 12b, 12c, 12g, 12g, and the surface modification layer shown in the example of the surface treatment of only O2 can also be used in the same manner.

Using the surface modification layers described herein, for example, including the examples of Table 3, Examples 4b, 4c, 4d, 4e, Tables 5 and 7-11, Examples 12a, 12b, 12c, 12g, 12j One advantage of the O2-only surface treatment embodiment is that the carrier can be reused in the same size. That is, the flakes can be removed from the support, and the surface modification layer removed from the support by non-destructive means (e.g., O2 or other plasma cleaning) can be reused without cutting the support in any way (e.g., at its edges). cutting).

Provides a controlled bond area

A second use of controlled bonding via a surface modification layer (comprising materials and associated bonding surface heat treatment) is to provide a controlled bonding area between the glass carrier and the glass flake. More specifically, through the use of surface-modified layers, controlled bonded regions can be created where sufficient separation force can separate the flake portions from the support without damage to the flake or support due to bonding, but throughout processing. Sufficient cohesion is still maintained to hold the sheet together relative to the carrier. Referring to FIG. 6 , the glass flake 20 may be bonded to the glass carrier 10 through a bonding region 40 . In the bonding area 40, the carrier 10 and the sheet 20 are covalently bonded to each other so that they are integrated. Furthermore, there is a controlled bonding region 50 with a perimeter 52 where the carrier 10 and sheet 20 are attached but can be separated from each other even after high temperature processing (eg processing at temperatures > 600°C). While Figure 6 shows ten controlled bonding regions 50, any suitable number (including one) may be provided. As illustrated above in Examples 2a, 2e, 3a, 3b, 4c, 4d, and 4e and in Table 5, the surface modification layer 30 (including material and bonding surface heat treatment) can be used to provide a glass bonding surface. Controlled bonding area 50 between carrier 10 and sheet 20 having a glass bonding surface. In particular, these surface modification layers may be formed within the perimeter 52 of the controlled bonding region 50 , either on the carrier 10 or on the sheet 20 . Thus, in order to form a covalent bond in the bonding region 40 or during device processing, when the article 2 is processed at high temperature, it may be provided between the carrier 10 and the sheet 20 in the area defined by the perimeter 52. Controlled bonding such that separation forces can separate the flake and support in this region (without catastrophic damage to the flake or support), but the flake and support do not delaminate during processing, including ultrasonic machining. Thus, the controlled bonding provided by the surface modification layer and any associated heat treatment of the present application can be improved upon based on the carrier concept in US '727. Specifically, while it was demonstrated that the carrier of US '727, by virtue of its bonded perimeter and non-bonded central region, survives FPD processing (including high temperature processing Ultrasonic machining such as resist strip processing remains challenging. Specifically, it was found that pressure waves in solution induce resonance in the non-bonded region of thin glass (unbonded as described in US'727), since in this region there is little or no bonded thin glass adhesion to the carrier. Standing waves will form in the thin glass, wherein, if the ultrasonic vibrations are of sufficient intensity, these waves can cause vibrations that can lead to fracture of the thin glass at the interface between bonded and non-bonded regions. This problem can be eliminated by minimizing the gap between the thin glass and the carrier, or by providing adequate bonding, or providing controlled bonding between the carrier 20 and the thin glass 10 in these regions 50 . The surface modification layer of the bonding surface (including the material and any associated heat treatment, as illustrated in Examples 2a, 2e, 3a, 3b, 4c, 4d, 4e and the examples in Table 5) controls the bonding energy so that at Sufficient bonding is provided between the glass bonding surface on sheet 20 and the glass surface on carrier 10 to avoid these undesirable vibrations in the controlled bonding region.

The portion of the foil 20 within the perimeter 52 can then be simply separated from the carrier 10 after machining and after the foil has been separated along the perimeter 57 during extraction of the desired part 56 with the perimeter 57 . Because the surface modification layers control the bonding energy to prevent permanent bonding of the flakes to the support, they can be used for processing at temperatures ≥ 600 °C. Of course, while these surface modification layers can control the bonding surface energy during processing at temperatures ≥ 600°C, they can also be used to create sheet and support combinations that can withstand processing at lower temperatures and Can be used for such lower temperature applications. In addition, when the thermal processing of the product will not exceed 400 ° C, such as the examples of Examples 2c, 2d, 4b, Tables 7-11 (including the examples of alternatives to the examples in Table 10), Example 12a , 12b, 12c, 12g, 12g, and O2-only surface treatment examples exemplified by surface modification layers can also be used in this same manner to control bond surface energy, in some cases depending on other processing requirements .

provide bonding area

A third use of controlled bonding via surface modification layers (comprising materials and associated bonding surface heat treatment) is to provide a bonded area between the glass carrier and the glass flake. Referring to FIG. 6 , the glass flake 20 may be bonded to the glass carrier 10 through a bonding region 40 .

In one embodiment of the third use, the bonding region 40, the carrier 10 and the sheet 20 may be covalently bonded to each other so that they are integrated. In addition, there is a controlled bond region 50 with a perimeter 52 where the carrier 10 and sheet 20 are bonded to each other sufficiently to survive processing and still allow the sheet to separate from the carrier, even at elevated temperatures (e.g., temperatures ≥ After processing at 600°C). Thus, as illustrated above in Examples 1a, 1b, 1c, 2b, 2c, 2d, 4a, 4b, 12d, 12e, 12f, 12h, and 12i, surface modification layer 30 (including material and bonding surface heat treatment) can be used To provide a bonding area 40 between the carrier 10 and the sheet 20 . Specifically, these surface modification layers and heat treatments may be formed outside the perimeter 52 of the controlled bonding region 50 , either on the carrier 10 or on the sheet 20 . Thus, when article 2 is processed at high temperatures, or when article 2 is processed or treated at high temperatures to form covalent bonds, carrier and sheet 20 will bond to each other in bond region 40 outside the region defined by perimeter 52 . Then, during the extraction of the desired part 56 with the perimeter 57, when it is desired to cut the sheet 20 and the carrier 10, the article can be separated along the line 5, since these surface modification layers and heat treatment cause the sheet 20 to form a bond with the carrier 10. Covalently bonded so they are a unit in that region. Because the surface modification layer provides a permanent covalent bond of the flakes to the support, they can be used for processing at temperatures ≥ 600 °C. In addition, when the thermal processing of the article or the thermal processing to initially form the bonded area 40 will be ≥ 400°C but less than 600°C, a surface modification layer (material as illustrated in Example 4a and heat treatment).

In the second embodiment of the third use, in the bonding area 40, the carrier 10 and the sheet 20 can be bonded to each other through controlled bonding via the various surface modification layers described above. In addition, there is a controlled bond region 50 with a perimeter 52 where the carrier 10 and sheet 20 are bonded to each other sufficiently to survive processing and still allow the sheet to separate from the carrier, even at elevated temperatures (e.g., temperatures ≥ After processing at 600°C). Thus, if processing will be performed at temperatures up to 600°C, and permanent or covalent bonding in region 40 is not desired, one can use examples 2e, 3a, 3b, 4c, 4d, 4e as above and Table The embodiment of FIG. 5 illustrates surface modification layer 30 (including material and bonding surface heat treatment) to provide bonding region 40 between the glass bonding surface of carrier 10 and the glass bonding surface of sheet 20 . In particular, these surface modification layers and heat treatments may be formed outside the perimeter 52 of the controlled bonding region 50 , which may be formed on the carrier 10 or on the sheet 20 . The controlled bonding region 50 may be formed with the same or a different surface modification layer than that formed in the bonding region 40 . Alternatively, if processing will be performed at temperatures only up to 400°C, and no permanent or covalent bonding in region 40 is desired, one can use examples 2c, 2d, 2e, 3a, 3b, 4b, as above, 4c, 4d, 4e, Examples of Table 5, Examples of Tables 7-11 (including examples discussed as alternatives to the examples of Table 10), Examples 12a, 12b, 12c, 12g, 12g, and O2 only An example of a surface treatment is illustrated for surface modification layer 30 (including material and bonding surface heat treatment) to provide bonding region 40 between the glass bonding surface of carrier 10 and the glass bonding surface of sheet 20 .

As an alternative to controlled bonding in region 50, there may be non-bonded regions in region 50, wherein said non-bonded regions may be regions of increased surface roughness (as described in US '727), or may be obtained by A surface modification layer as illustrated in Example 2a was provided.

Overall annealed or overall machined

A fourth use of the controlled bonding approach described above is bulk annealing of stacks of glass sheets. Annealing is a thermal process that achieves compaction of glass. Compaction involves reheating the glass body to a temperature below the softening point of the glass but above the maximum temperature reached in subsequent processing steps. This enables structural rearrangement and scale relaxation in the glass before, rather than during, subsequent processing. Annealing prior to subsequent processing is advantageous for maintaining precise alignment and/or flatness in the glass body during subsequent processing, since in the manufacture of flat panel display devices, structures fabricated from many layers need to be made with very tight tolerances alignment, even after exposure to high-temperature environments. If the glass is compacted in a high temperature process, structural layers deposited on the glass prior to the high temperature process may not be accurately aligned with structural layers deposited after the high temperature process.

It is economically attractive to compact the glass sheets in the stack. However, this requires interlayering or separation of adjacent sheets to avoid sticking. At the same time, it is beneficial to maintain the sheet extremely flat and have an optical quality or pristine surface finish. Also, for certain glass sheet stacks, such as sheets with small surface areas, it may be advantageous to "stick" the glass sheets together during annealing so that they can be easily moved as a unit without separation, but in After the annealing process they are easily separated from each other (by eg peeling off), so that the sheets can be used individually. Alternatively, it may be advantageous to anneal the stack of glass sheets in which selected ones of the glass sheets are prevented from permanently adhering to each other while other sheets of the glass sheet or portions of these other glass sheets (e.g. their surroundings) boundaries) are permanently bonded to each other. Alternatively, it may be advantageous to stack the glass sheets in an ensemble such that the perimeters of selected pairs of adjacent sheets in the stack are selectively permanently bonded. The above-described means of controlling bonding between glass sheets can be used to achieve the aforementioned bulk annealing and/or selective bonding. In order to control bonding at any particular interface between adjacent sheets, a surface modification layer may be used on at least one of the major surfaces facing that interface.

One embodiment of a stack of glass sheets suitable for bulk annealing or bulk permanent bonding in selected areas (eg, around the perimeter) will now be described with reference to FIGS. 7 and 8 . 7 is a schematic side view of a stack 760 of glass sheets 770-772, and FIG. 8 is an exploded view thereof for further explanation purposes.

Stack 760 of glass sheets may include glass sheets 770-772, and a surface modification layer 790 (to control bonding between glass sheets 770-772). Additionally, the stack 760 may include cover sheets 780, 781 disposed at the top and bottom of the stack, and may include a surface modification layer 790 between the cover and adjacent glass sheets.

As shown in FIG. 8, glass sheets 770-772 include a first major surface 776 and a second major surface 778, respectively. The glass sheet may be made of any suitable glass material, such as aluminosilicate glass, borosilicate glass or aluminoborosilicate glass. Furthermore, the glass can be alkali-containing or alkali-free. The glass sheets 770-772 may each have the same composition, or the sheets may be of different compositions. Additionally, the glass sheet can be of any suitable type. That is, for example, glass sheets 770-772 may all be the carriers described above, may all be the sheets described above, or may alternately be carriers and sheets. It may be advantageous to have a stack of carriers and a separate stack of lamellae when the carrier versus the lamellae requires different time-temperature cycles for bulk annealing. Alternatively, with the correct surface modifying layer material and placement, it may be desirable to have stacks of alternating supports and flakes so that, if desired, support and flake pairs (i.e., those forming the article) can be integrated in the bulk, at a later stage of processing covalently bond to each other while retaining the ability to separate adjacent articles from each other. Additionally, there may be any suitable number of glass sheets in the stack. That is, while only three glass sheets 770-772 are shown in FIGS. 7 and 8, any suitable number of glass sheets may be included in the stack 760.

In any particular stack 760, any one of the glass sheets may contain no surface modification layers, contain one surface modification layer, or contain two surface modification layers. For example, as shown in FIG. 8, sheet 770 includes no surface modifying layer, sheet 771 includes one surface modifying layer 790 on its second major surface 778, and sheet 772 includes two surface modifying layers 790. , wherein each of its major surfaces 776, 778 has one such surface modifying layer.

Cover sheets 780, 781 may be any material that suitably withstands time-temperature cycling (not just time and temperature, but also with respect to other related considerations such as like degassing) for a given process. Advantageously, the cover sheet can be made of the same material as the glass sheet to be processed. Where cover sheets 780, 781 are present and, after subjecting the stack through a given time-temperature cycle, they would undesirably bond to the glass sheet, there may be a gap between the glass sheet 771 and the cover sheet 781 and and/or include a surface modification layer 790 between the glass sheet 772 and the cover sheet 780, if appropriate. When present between the cover and the glass sheet, the surface modification layer can be on the cover (as shown by cover 781 and adjacent sheet 771), and the surface modification layer can be on the glass sheet (as shown by cover 780 and sheet 772 ), or the surface modification layer can be on both the cover and the adjacent sheet (not shown). Alternatively, if cover sheets 780, 781 are present but are of a material that will not bond to adjacent sheets 772, 772, no surface modification layer 790 is required in between.

Between adjacent sheets in the stack, there is an interface. For example, between adjacent ones of glass sheets 770-772, interfaces are defined, namely, interface 791 between sheet 770 and sheet 771 and interface 792 between sheet 770 and sheet 772. Furthermore, when cover sheets 780 , 781 are present, there is an interface 793 between cover 781 and sheet 771 , and an interface 794 between sheet 772 and cover 780 .

To control the bonding at a given interface 791, 792 between adjacent glass sheets, or the bonding at a given interface 793, 794 between a glass sheet and a cover sheet, a surface modification layer 790 may be used. For example, as shown, at interfaces 791, 792, respectively, there is a surface modification layer 790 on at least one major surface facing the interface. For example, for interface 791 , second major surface 778 of glass sheet 771 includes surface modification layer 790 to control bonding between sheet 771 and adjacent sheet 770 . Although not shown, the first major surface 776 of the sheet 770 may also include a surface modifying layer 790 thereon to control adhesion to the sheet 771, i.e., on each major surface toward any particular interface. There may be a surface modification layer.

At any given interface 791-794, a particular surface-modifying layer 790 (and any associated surface-modifying treatment, such as applying a particular surface-modifying treatment to a particular surface) can be selected for the major surfaces 776, 778 facing that particular interface 791-794. heat treatment on that particular surface prior to the protective layer, or surface heat treatment of the surface that may be in contact with the surface modifying layer) to control the bonding between adjacent sheets so that for a given time-temperature to which the stack 760 is subjected loop to achieve the desired output.

If it is desired to anneal the stack of glass sheets 770-772 as a whole at temperatures up to 400°C, and to separate each glass sheet from each other after the annealing process, the 3b, 4b-4e, Examples of Table 5, Examples of Tables 7-11 (including examples discussed as alternatives to the examples of Table 10), Examples 12a, 12b, 12c, 12g, 12g or just O2 The material of any of the surface treatment embodiments, in combination with any associated surface preparation, is used to control adhesion at any particular interface (eg, interface 791 ). More specifically, first surface 776 of sheet 770 will be considered "thin glass" in Tables 2-4, and second surface 778 of sheet 771 will be considered "carrier" in Tables 2-4 , and vice versa. An appropriate time-temperature cycle with temperatures up to 400°C can then be selected based on the degree of compaction required, the number of sheets in the stack, and the size and thickness of the sheets to achieve the required time throughout the stack -temperature.

Similarly, if it is desired to bulk anneal the stack of glass sheets 770-772 at temperatures up to 600°C, and to separate each glass sheet from each other after the annealing process, one can use , 4c, 4d, 4e, or any of the embodiments of Table 5, in combination with any relevant surface preparation, to control bonding at any particular interface (eg, interface 791). More specifically, first surface 776 of sheet 770 will be considered "thin glass" in Tables 2-4, and second surface 778 of sheet 771 will be considered "carrier" in Tables 2-4 , and vice versa. An appropriate time-temperature cycle with temperatures up to 600°C can then be selected based on the degree of compaction required, the number of sheets in the stack, and the size and thickness of the sheets to achieve the required time throughout the stack -temperature.

In addition, bulk annealing and bulk article shaping can be pre-formed by proper configuration of sheet stacks and surface modifying layers between their pairs. If it is desired to bulk anneal the stack of glass sheets 770-772 at temperatures up to 400°C, and then bulk covalently bond adjacent pairs of sheets to each other to form article 2, then appropriate material and related surface preparation. For example, around the perimeter (or other desired bonding area 40), the bonding at the interface between the pair of glass sheets (e.g., sheets 770 and 771) to be formed into article 2 can be controlled in the following manner: (i ) according to Example 2c, 2d, 4b, the examples of Tables 7-11 (including the examples discussed as alternatives to the examples of Table 10), Examples 12a, 12b, 12c, 12g, 12g, or just O2 surface treatment The material of any one of the embodiments, along with any associated surface preparation, around the perimeter of the sheets 770, 771 (or other desired bonding areas 40); and (ii) according to embodiments 2a, 2e, 3a, 3b, 4c, 4d, 4e, or any of the examples of Table 5, along with any associated surface preparation, on the interior region of the sheet 770, 771 (i.e., the perimeter treated in (i) internal areas, or the desired controlled bond area 50) where it is desired to separate the sheets from each other. In this case, the device in the controlled bonding region 50 can then be processed at temperatures up to 600°C.

Appropriate selection of materials and heat treatments can be made to be compatible with each other. For example, any material 2c, 2d or 4b can be used for the bonding area 40, the material according to embodiment 2a for the controlled bonding area. Alternatively, the heat treatment of the bonded and controlled bonded areas can be appropriately controlled so that the effect of heat treatment in one area can minimize the negative impact on the desired degree of bonding in an adjacent area.

After proper selection of the surface modification layer 790 and associated heat treatment for the glass sheets in the stack, the sheets can be suitably arranged into a stack and then heated to as high as 400°C such that all sheets in the entire stack undergo Anneal the bulk without making them permanently bond to each other. The stack can then be heated to up to 600°C to form covalent bonds in the desired bonding regions of adjacent sheet pairs to form an article 2 having bonded regions and a controlled pattern of bonded regions. The materials of Examples 2a, 2e, 3a, 3b, 4c, 4d, 4e, Table 5, and the associated heat treatment may be used for a pair of sheets to be covalently bonded through the bonding region 40 to form the article 2 The bonding at the interface between another pair of such sheets forming separate but adjacent articles 2 is controlled so that adjacent articles 2 are not covalently bonded to each other. In this same manner as controlling the bond between adjacent articles, it is possible to control the bond between an article and any cover sheet present in the stack.

Furthermore, article 2 may be formed in one piece from stack 760 without prior annealing of the same stack 760, similarly as described above. Conversely, the sheets may have been annealed separately, or annealed and separated from different stacks, after which they are configured for the controlled bonding required in the stack to create the article as a whole. From the bulk annealing approach described immediately above, and then forming the article in the bulk from one and the same stack, the bulk annealing is simply omitted.

While only the manner in which the controlled bonding at interface 791 is described in detail, it is clear that it may be possible at interface 792 or (where there are more than three glass sheets in the stack, or that the cover sheet would be undesirably bonded to the glass sheet case) in the same way at any other interface that may exist in a particular stack. In addition, while the same means of controlling bonding may be used at any of the interfaces 791, 792, 793, 794 that exist, different means of controlling bonding as described above may be used at different interfaces, as desired. The bonded types of forms produce the same or different output.

During the bulk annealing process described above, or when forming the article 2 in the bulk, when HMDS is used as a material to control bonding at the interface, and the HMDS is exposed to the outer perimeter of the stack, when it is desired to prevent For covalent bonding, heating above about 400°C should be performed in an oxygen-free atmosphere. That is, if the HMDS is exposed (at temperatures above about 400° C.) to an oxygen content in the atmosphere sufficient to oxidize the HMDS, bonding in any such region where the HMDS oxidizes will become bonded between adjacent glass sheets. covalent bonding between them. At higher temperatures (eg, greater than about 400° C.), other alkylhydrocarbon silanes are similarly exposed to the effects of oxygen, such as ethyl, propyl, butyl, or steryl silanes. Similarly, if other materials are used for the surface modification layer, the bulk annealing environment should be selected so that the material does not degrade with the annealing time-temperature cycling. As used herein, free of oxygen may mean an oxygen concentration of less than 1000 ppm by volume, more preferably less than 100 ppm by volume.

Once the stack of sheets has been bulk annealed, individual sheets can be separated from the stack. Individual sheets may be treated (eg, by oxygen plasma, heating at a temperature > 400° C. in an oxygen environment, or by chemical oxidation, SC1 or SC2 ) to remove the surface modification layer 790 . Individual sheets can be used as desired, for example as substrates for electronic devices such as OLEDs, FPDs or PV devices.

The methods of bulk annealing or bulk machining described above have the advantage of maintaining the surface of the cleaning sheet in an economical manner. More specifically, there is no need to keep the sheet in a clean environment from start to finish, as is the case with clean room annealing lehrs. Conversely, stacks can be formed in a clean environment and then processed in a standard annealing lehr (i.e., one whose cleanliness is not controlled) without causing damage to the sheet surface since there is no fluid flow between the sheets. get dirty. Thus, the sheet surface is protected from the environment in which the sheet stack is annealed. After annealing, the sheet stack can be easily transferred to another processing area (in the same equipment or in a different equipment) because the sheets maintain some degree of adhesion, but also remain separable from each other after being subjected to sufficient force without damaging the sheet. That is, (for example) a glass manufacturer can assemble and anneal a stack of glass sheets, then transfer the sheets as a stack that stays together during shipping (without worrying about their separation during shipping), at After reaching its final location, the sheets can be separated from the stack by the consumer, who may be using a single sheet or using smaller groups of sheets. Once separation is desired, the sheet stack can be processed again in a clean environment (if necessary after stack cleaning).

Examples of bulk annealing

Glass substrates fresh from the fusion drawing process were used. The fusion drawn glass composition is as follows, in mole percent: SiO2 (67.7), Al2O3 (11.0), B2O3 (9.8), CaO (8.7), MgO (2.3), SrO (0.5). Seven (7) 0.7 mm thick, 150 mm diameter fused drawn glass substrates were patterned by lithography with 200 nm deep fiducial/vernier using HF. Two nanometers (2nm) of plasma deposited fluoropolymer was applied as a surface modification layer to all bonding surfaces of all glass substrates, i.e. every surface of a substrate facing the other substrate was coated , the surface energy of each sheet thus obtained is about 35 mJ/m ² . Seven coated individual glass substrates were brought together to form a single, thick substrate (referred to as a "glass stack"). The glass stack was annealed in a nitrogen-purged tube furnace from 30°C to 590°C over a 15-minute period, held at 590°C for 30 minutes, and then cooled to approximately 230°C over a 50-minute period, The glass stack was then removed from the furnace and cooled to room temperature of about 30° C. within about 10 minutes. After cooling, the substrate was removed from the oven and the substrate was easily separated into individual sheets using a razor blade wedge (ie no general or partial permanent bonding of the sample occurred). Compaction was measured on each individual substrate by comparing a glass reference to an unannealed quartz reference. The substrate alone was found to be compacted to about 185 ppm. The two substrates were subjected to the second annealing cycle (590° C./30 minutes hold) as described above as separate samples (not stacked together). The compaction was measured again and found to be further compacted to less than 10 ppm (actually 0-2.5ppm). Thus, the inventors of the present invention have demonstrated that individual glass sheets can be coated, stacked and heat treated at high temperature to achieve compaction, cooling, separation into individual sheets, and have <10ppm (or even < 5 ppm) scale change (compared to its size after the first heat treatment).

Although the furnace is purged with nitrogen in the annealing examples described above, other gases may be used to purge the furnace, including air, argon, oxygen, _CO , or combinations thereof, depending on the annealing temperature and in the particular environment , the stability of the surface modification layer material at these temperatures. Alternatively, for an inert atmosphere, the furnace described above can be annealed in a vacuum environment.

Additionally, although not shown, the glass may be annealed in roll form rather than sheet form. That is, a suitable surface modification layer can be formed on one or both sides of the glass ribbon before the ribbon is wound. The entire ribbon can be subjected to the same treatment as described above for the sheet, the entire coil of glass being annealed such that the glass on one turn does not stick to the glass on the adjacent turn. After unwinding, the surface modification layer may be removed by any suitable process.

degassing

Polymeric adhesives used in typical die attach applications are typically 10-100 microns thick, losing about 5% of their mass at or near their temperature limit. For such materials developed from thick polymer films, mass loss or outgassing is readily quantified by mass spectrometry. On the other hand, it is more challenging to measure outgassing of thin surface treatments with a thickness less than or equal to about 10 nm, such as plasma polymers or self-assembled monolayer surface modification layers as described above and thin layers of pyrolyzed silicone oil. For such materials, mass spectrometry is not sensitive enough. However, there are many other ways to measure outgassing.

A first way to measure small amounts of outgassing is based on surface energy measurements and will be described with reference to FIG. 9 . For this test, the setup shown in Figure 9 can be used. A first substrate or support 900 having a surface modification layer to be tested thereon presents a surface 902, a surface modification layer corresponding to the composition and thickness of the surface modification layer 30 to be tested. A second substrate or cover 910 is placed with its surface 912 in close proximity to, but not in contact with, the surface 902 of the carrier 900 . Surface 912 is the uncoated surface, ie, the bare surface of the material from which the covering is made. Spacers 920 are placed at various points between the carrier 900 and the cover 910 to maintain them in a separated relationship. The spacer should be thick enough to separate the cover 910 from the carrier 900 to allow mutual movement of the materials, but thin enough so that the amount of contamination of the surfaces 902 and 912 by the chamber atmosphere during testing is minimized. Carrier 900 , spacer 920 and cover 910 together form test article 901 .

Before assembling the test article 901, the surface energy of the bare surface 912 was measured as the surface energy of the surface 902 (ie the surface of the support 900 on which the surface modification layer was provided). The surface energy is shown in Figure 10, by fitting the contact angles of the three test liquids (water, diiodomethane, and hexadecane) to the Wu model to simultaneously measure the polar and dispersive components.

After assembly, the test article 901 is placed in the heating chamber 930 and heated through a time-temperature cycle. Heating was performed at atmospheric pressure and flowing _N2 gas (ie, in the direction of arrow 940, flowing at a rate of 2 standard liters per minute).

During the heating cycle, changes in surface 902, including changes in the surface modification layer due to, for example, evaporation, pyrolysis, decomposition, polymerization, reaction with supports, and dewetting, are evidenced by changes in the surface energy of surface 902. A change in the surface energy of the surface 902 by itself does not necessarily mean that outgassing of the surface modified layer has occurred, but does indicate an overall instability of the material at this temperature due to changes in its properties due to mechanisms such as those described above. Variety. Therefore, the smaller the change in surface energy of surface 902, the more stable the surface modification layer. On the other hand, because of the close proximity of surface 912 to surface 902 , any material outgassed from surface 902 will be collected on surface 912 and will change the surface energy of surface 912 . Thus, the change in surface energy of surface 912 is a proxy for degassing of the surface modifying layer present on surface 902 .

Thus, one test for outgassing uses the change in surface energy of the covered surface 912 . Specifically, if the change in surface energy of surface 912 is > 10 mJ/m2, outgassing is present. Surface energy changes of this magnitude are consistent with contamination that can lead to loss of film adhesion or cracking of material properties and device performance. The surface energy change of ≤5mJ/m2 is close to the repeatability of surface energy measurement and the non-uniformity of surface energy. This small change is consistent with minimal outgassing.

In the tests that produced the results of FIG. 10, the carrier 900, cover 910, and spacer 920 were made from Eagle XG glass (an alkali-free aluminoborosilicate display grade glass available from Corning Incorporated, Corning, NY), but not This must be the case. The carrier 900 and cover 910 have a diameter of 150 mm and a thickness of 0.63 mm. Typically, carrier 910 and cover 920 are made of the same material of carrier 10 and sheet 20, respectively, that it is desired to perform an outgassing test. During this test, the silicon spacer was 0.63 mm thick, 2 mm wide and 8 cm long, creating a gap of 0.63 mm between surfaces 902 and 912 . During this test, the integrated chamber 930 in the MPT-RTP600s rapid thermal processing equipment was cycled at a rate of 9.2°C/min from room temperature to the test limit temperature, where it was maintained as shown in the "annealing time" Various times, then cooled to 200°C at furnace rate. After the oven was cooled to 200° C., the test article was taken out, and after the test article was cooled to room temperature, the surface energies of surfaces 902 and 912 were measured again, respectively. So, for example, for material #1, line 1003, the data on the change in surface energy of the covering surface tested to a limit temperature of 450°C, the data is collected as follows. The 0 minute data point shows a surface energy of 75 mJ/m2 (millijoules per square meter), which is that of bare glass (ie, has not been time-temperature cycled). The 1 minute data point represents the surface energy measured after the following time-temperature cycling: Article 901 (with Material #1 on support 900 used as a surface modification layer to present surface 902) was placed at room temperature and atmospheric pressure In the heating chamber 903; the chamber is heated to the test limit temperature of 450°C at a rate of 9.2°C/min, the N2 gas flow rate is 2 standard liters/min, and the test limit temperature of 450°C is maintained for 1 minute; The chamber is cooled to 300°C at a rate of °C/min, and the article 901 is removed from the chamber 930; the article is then cooled to room temperature (without the N2 flowing atmosphere); the surface energy of the surface 912 is then measured and plotted as line 1003 on the 1 minute point. The remaining data points for material #1 (lines 1003, 1004) as well as for material #2 (lines 1203, 1204), for material #3 (lines 1303, 1304), for material #4 were then determined in a similar manner. Data points (lines 1403, 1404), data points of material #5 (lines 1503, 1504), data points of material #6 (lines 1603 and 1604), and material #7 (lines 1703, 1704), annealing time (minutes) corresponding The holding time at the test limit temperature (450°C or 600°C, as appropriate). The lines 1001 , 1002 , 1201 , 1202 , 1301 , 1302 , 1401 , 1402 , 1501 , 1502 , 1601 , 1602 representing the surface energies of the surface 902 of the corresponding surface modification layer materials (Material #1-7) were determined in a similar manner , 1701 and 1702, except that the surface energy of surface 902 was measured after each time-temperature cycle.

The above assembly process and time-temperature cycling were performed for seven different materials as shown below and the results are shown in FIG. 10 . Of the 7 materials, materials #1-4 and 7 correspond to the surface modification layer materials described above. Materials #5 and #6 are comparative examples.

Material #1 is a CHF3-CF4 plasma polymerized fluoropolymer. This material is consistent with the surface modification layer material in Example 3b above. As shown in Figure 10, lines 1001 and 1002 show no significant change in the surface energy of the carrier. Therefore, the material is very stable at temperatures of 450-600°C. Furthermore, as shown by lines 1003 and 1004, the covered surface energy also does not change significantly, ie, changes < 5 mJ/m2. Therefore, at 450-600°C, there is no outgassing associated with this material.

Material #2 is a phenylsilane, self-assembled monolayer (SAM) deposited from a 1% solution of phenyltriethoxysilane in toluene and cured in a vacuum oven at 190°C for 30 minutes. This material is consistent with the surface modification layer material in Example 4c above. As shown in Figure 10, lines 1201 and 1202 indicate partial changes in surface energy on the support. As stated above, this indicates a partial change in the surface modification layer, as a comparison, Material #2 was slightly less stable than Material #1. However, as shown by lines 1203 and 1204, the change in surface energy of the support was < 5 mJ/m2, showing that the change in the surface modification layer did not result in outgassing.

Material #3 is pentafluorophenylsilane, a SAM deposited from a 1% solution of pentafluorophenyltriethoxysilane in toluene and cured in a vacuum oven at 190°C for 30 minutes. This material is consistent with the surface modification layer material in Example 4e above. As shown in Figure 10, lines 1301 and 1302 indicate partial changes in surface energy on the support. As noted above, this indicates a partial change in the surface modification layer, as a comparison, Material #3 was slightly less stable than Material #1. However, as shown by lines 1303 and 1304, the change in surface energy of the support was < 5 mJ/m2, showing that the change in the surface modification layer did not result in outgassing.

Material #4 is hexamethyldisilazane (HMDS) deposited from vapor in a YES HMDS oven at 140°C. This material is consistent with the surface modification layer material in Example 2b of Table 2 above. As shown in Figure 10, lines 1401 and 1402 indicate partial changes in surface energy on the support. As stated above, this indicates a partial change in the surface modification layer, as a comparison, Material #4 was slightly less stable than Material #1. Furthermore, the change in surface energy of the support for material #4 was greater than that of either material #2 and #3, for comparison, indicating that material #4 was slightly less stable than materials #2 and #3. However, as shown by lines 1403 and 1404, the change in surface energy of the support was < 5 mJ/m2, showing that the change in the surface modification layer did not result in outgassing affecting the surface energy of the cover. However, this is consistent with the way HMDS degasses. That is, HMDS degasses ammonia and water, which does not affect the surface energy of the covering, and does not affect some electronic manufacturing equipment and/or processes. On the other hand, other problems may exist when outgassing products are trapped between the sheet and support, as described below for the second outgassing test.

Material #5 is glycidoxypropylsilane, a SAM deposited from a 1% solution of glycidoxypropyltriethoxysilane in toluene and cured in a vacuum oven at 190°C for 30 minutes. This is a comparative example material. While the surface energy of the carrier varies less as shown by lines 1501 and 1502 , the surface energy of the covering varies significantly as shown by lines 1503 and 1504 . That is, while material #5 was relatively stable on the support surface, it did degas a significant amount of material onto the cover surface, resulting in a change in cover surface energy > 10 mJ/m2. Although the surface energy was within 10 mJ/m2 at the end of 10 minutes at 600°C, it did vary by more than 10 mJ/m2 during this period. See, for example, the 1-minute and 5-minute data points. While not wishing to be bound by theory, the slight rise in surface energy from 5 minutes to 10 minutes may be due to a portion of the degassed material decomposing and leaving the covering surface.

Material #6 is DC704, a silicone coating prepared by dispersing 5 mL of Dow Corning 704 Diffusion Pump Oil Tetramethyltetraphenyltrisiloxane (available from Dow Corning) onto the carrier, Place on a hot plate at 500 °C in air for 8 min. The cessation of visual smoking was counted as completion of the sample preparation. After preparing the samples in the manner described above, the outgassing test described above was performed. This is a comparative example material. As shown in Figure 10, lines 1601 and 1602 indicate partial changes in surface energy on the support. As stated above, this indicates a partial change in the surface modification layer, as a comparison, Material #6 is not as stable as Material #1. In addition, as shown by lines 1603 and 1604, the surface energy of the carrier changes by ≥ 10 mJ/m2, showing significant outgassing. More specifically, at the test-limited temperature of 450°C, the 10-minute data point shows a drop in surface energy of about 15 mJ/m2, and even more for the 1-minute and 5-minute data points. Similarly, the covered surface energy drop at the 10 minute data point was about 25 mJ/m2 for the covered surface energy change during cycling at the test limit temperature of 600°C, slightly greater than 5 minutes and slightly less than 1 minute. In general, however, the material showed significant outgassing throughout the range tested.

Material #7 is a CH4-H2 plasma deposited polymer followed by brief N2-O2 and N2 plasma treatments. The material was similar to the surface modification layer in the examples in Table 11 above. As shown in Figure 10, lines 7001 and 7002 show no significant change in the surface energy of the support. Therefore, the material is very stable at temperatures of 450-600°C. Furthermore, as shown by lines 7003 and 7004, the covered surface energy also does not change significantly, ie, changes < 5 mJ/m2. Therefore, at 450-600°C, there is no outgassing associated with this material.

Notably, for materials #1-4 and 7, the surface energies throughout the time-temperature cycles indicated that the covered surface maintained a surface energy consistent with that of the bare glass, ie no material outgassed from the support surface was collected. In the case of material #4, as described with respect to Table 2, the way the support and flake surfaces were prepared (through surface modification layers such that the flakes were bonded to the support) made a big difference in whether the article would survive FPD processing. Thus, while the example of material #4 shown in FIG. 10 may not have outgassed, the material may or may not have survived the 400°C or 600°C tests, as described with respect to Table 2.

A second way to measure small amounts of outgassing is based on self-assembled articles, ie, flakes bonded to a support via a surface modification layer, using the change in percent cell area to determine outgassing. That is, air bubbles formed between the support and the flake during heating of the article indicate degassing of the surface-modified layer. As mentioned above with respect to the first outgassing test, it is difficult to measure outgassing of very thin surface modified layers. In this second test, the outgassing under the flakes may be limited by the strong adhesion between the flakes and the support. However, layer thicknesses ≤10 nm (e.g. plasma-polymerized materials, SAM and pyrolytic silicone oil surface treatments) may still generate bubbles during heat treatment, even if they have a small absolute mass loss. And the generation of air bubbles between the wafer and the carrier can cause problems with patterning, photolithographic processing, and/or alignment problems during fabrication of devices onto the wafer. Furthermore, blistering at the boundary of the bonded area between the flake and carrier can lead to problems with process fluids from one process contaminating downstream processes. A change in percent bubble area ≥ 5 is significant, indicates degassing, and is undesirable. On the other hand, a percent change of bubble area ≤ 1 is insignificant, indicating the absence of outgassing.

Bonded thin glass has an average bubble area of 1% in a manually bonded Class 1000 clean room. The % bubbles in the bonded support are related to the cleanliness of the support, thin glass sheet and surface preparation. These initial defects thus act as nucleation sites for bubble growth after heat treatment, after which any variation in bubble area of less than 1% falls within the variability of sample preparation. For this test, a commercially available desktop scanner (Epson Expression 10000XL Photo) with a clear unit was used to obtain a first scan of the bonded area of the sheet and support immediately after bonding image. Parts were scanned using standard Epson software using 508dpi (50 microns/pixel) and 24bit (bit) RGB. Image processing software first prepares the image by stitching images of different sections of the sample into a single image and removing scanner artifacts (via a calibration reference scanned without the sample in the scanner) if necessary. The bonded areas are then analyzed using standard image processing techniques such as thresholding, hole filling, erosion/dilation and smudge analysis. The newer Epson Fast 11000XL can also be used for photography in a similar fashion. In transmission mode, air bubbles in the bonded area are visually visible in the scanned image and a value for the area of the air bubble can be determined. The bubble area was then compared to the total bonded area (ie, the total overlap area between the sheet and support) to calculate the % area of bubbles in the bonded area relative to the total bonded area. The samples were then heat-treated in an MPT-RTP600s rapid thermal processing system at test-limited temperatures of 300°C, 450°C, and 600°C under N2 atmosphere for up to 10 minutes. Specifically, the time-temperature cycle performed included the following: inserting the article into a heated chamber at room temperature and atmospheric pressure; then heating the chamber to the test limit temperature at a rate of 9 °C/min; maintaining the chamber at the test limit temperature for 10 minutes; then cool the chamber to 200°C at oven rate; remove the article from the chamber and cool to room temperature; then scan the article a second time with the optical scanner. The % Bubble Area of the second scan was then calculated as described above and compared to the % Bubble Area of the first scan to determine the change in % Bubble Area (Δ% Bubble Area). As noted above, a change in bubble area of > 5% is evident, indicating degassing. Due to the variability of the original % bubble area, the % bubble area change was chosen as the measurement standard. That is, most of the surface modification layers had about 2% bubble area in the first scan due to handling and cleanliness after the flakes and supports were prepared and before they were bonded. However, there may be variations between various materials. In this second outgassing test method, the same materials #1-7 as described for the first outgassing test method were used again. Among these materials, materials #1-4 exhibited about 2% bubble area in the first scan, while materials #5 and #6 showed significantly larger bubble area in the first scan, i.e. about 4%.

The results of the second outgassing test will be described below with reference to FIGS. 11 and 12 . The outgassing test results for materials #1-3 and #7 are shown in Figure 11, while the outgassing test results for materials #4-6 are shown in Figure 12.

The results for Material #1 are shown in Figure 11 as square data points. It can be seen from the figure that the % bubble area change is close to zero for the test limit temperatures of 300°C, 450°C and 600°C. Therefore, Material #1 showed no outgassing at these temperatures.

The results for Material #2 are shown in Figure 11 as diamond shaped data points. It can be seen from the figure that the % bubble area change is less than 1 for the test limit temperature of 450°C and 600°C. Therefore, Material #2 showed no outgassing at these temperatures.

The results for Material #3 are shown in Figure 11 as triangular data points. As can be seen from the figure, similar to the results for material #1, the % bubble area change is close to zero for the test limit temperatures of 300°C, 450°C, and 600°C. Therefore, Material #1 showed no outgassing at these temperatures.

The results for Material #7 are shown in Figure 11 as crossed data points. It can be seen from the figure that the % bubble area change is close to zero for the test limit temperatures of 300°C and 450°C. Therefore, Material #7 showed no outgassing at these temperatures. Material #7 showed a % Bubble Area change of less than 2 for the test limit temperature of 600°C. Therefore, Material #7 exhibits minimal outgassing at this temperature in most cases.

The results for Material #4 are shown in Figure 12 as circular data points. As can be seen from the graph, for the test limit temperature of 300°C, the % bubble area change is close to zero, but for some samples, at the test limit temperature of 450°C and 600°C, it is close to 1%, for other samples of the same material , which is about 5% at the test limit temperatures of 450°C and 600°C. The results for material #4 were very inconsistent depending on how the flake and support surface to which the HMDS material was bonded was prepared. The manner in which the samples were performed was dependent on the manner in which the samples were prepared, which is consistent with the Examples and related discussion described above for this material in Table 2. It should be noted that for this material, the samples with nearly 1% variation in cell area at the test limit temperatures of 450°C and 600°C did not allow separation of flakes and support according to the separation test described above. That is, strong adhesion between flakes and support may have limited bubble generation. On the other hand, samples with a % bubble area change close to 5% did allow separation of flakes and support. Thus, samples that did not have degassing had the undesirable result of increased adhesion after temperature treatment, which allowed the support and flakes to stick together (preventing removal of the flakes from the support), while samples that allowed the removal of flakes and support had undesired results. Desired degassing results.

The results for material #5 are shown in Figure 12 as triangular data points. It can be seen from the figure that for the test limit temperature of 300°C, the change in % bubble area is about 15%, which is greater than that of the higher test limit temperatures of 450°C and 600°C. Thus, Material #5 exhibited significant outgassing at these temperatures.

The results for Material #6 are shown in Figure 12 as square data points. As can be seen from the graph, the % Bubble Area varies by more than 2.5% for the test-limited temperature of 300°C, and by more than 5% for the test-limited temperatures of 450°C and 600°C. Thus, Material #6 exhibited significant outgassing at the test-limited temperatures of 450°C and 600°C.

Bonding polymer surfaces to glass surfaces

Displays on polymer sheets such as polyethylene naphthalate (PEN), polyethylene terephthalate (PET), and polyimide (PI) have been demonstrated where device fabrication is PEN Sheet-sheet format laminated to a glass carrier. For polymer layers up to 100 microns thick, adhesives are commonly used to laminate PEN and PET to glass carriers for sheet-to-sheet processing. The weight loss of these adhesives during device processing is typically greater than 1%, which creates contamination challenges due to solvent outgassing. In addition, complete removal of the adhesive is challenging, so glass carriers are usually not reused.

This application describes the use of a thin surface-modified layer to form moderate adhesion between a glass support and a polymer sheet to produce a controlled temporary bond that is strong enough to withstand TFT processing but weak enough to allow debonding Knot. While heat, vacuum, solvent, and acid, as well as ultrasonic flat panel display (FPD) processing require strong bonds for the bonding of thin polymer sheets to supports, the various surface modification layers discussed herein enable this controlled bonding. For processing polymer flakes on glass supports. Furthermore, controlled bonding enables removal of the polymer flakes from the carrier without catastrophic damage to the polymer flakes or the glass carrier, thereby providing a reusable glass carrier.

There are 3 transistor technologies for mass production with PFD backplane fabrication: amorphous silicon (aSi) bottom-gate TFT, polysilicon (pSi) top-gate TFT, and amorphous oxide (IGZO) bottom-gate TFT. These techniques all require high temperature processing steps >300C. This requirement for the substrate to be capable of high temperature processing and for chemical, mechanical and vacuum compatibility constitutes a major limitation for the industrialization of flexible displays on existing flexible substrates such as polymers. The general process begins with cleaning of the polymer substrate, usually by ultrasonic or supersonic agitation in a hot alkaline solution, followed by rinsing with DI water. The device structures are fabricated in subtractive cycles of material etching followed by multiple material depositions and photolithographic patterning. Deposition of metals, dielectrics by vacuum processes such as sputtering of metals, transparent conducting oxides and oxide semiconductors, chemical vapor deposition (CVD) deposition of amorphous silicon, silicon nitride and silicon dioxide at elevated temperatures and semiconductor materials. Laser and flash lamp anneals achieved p-Si crystallization without overheating the substrate, but uniformity was problematic and performance was poor compared to glass substrates. Layers are patterned by photolithographic patterning and etching of a polymer resist, followed by resist stripping. Both vacuum plasma (dry) etching and acidic wet etching processes are used. In FPD processing, the photoresist is typically stripped by hot solvents, usually utilizing ultrasound or super-loud vibrations.

Removing the thick adhesive layer prevents the reusability of the carrier. For a polymer binder to be useful in FPD processing, it must have good chemical resistance in solvents, strong acids, and strong bases. However, these same properties make removal problematic. And for layers up to 100 microns thick, plasma processing is not practical to remove the layer. A major challenge in the fabrication of organic thin film transistors is the lamination of thin polymer sheets to the carrier.

This application describes a method of controlling the temporary bonding of polymer sheets to glass carriers for FPD processing, and describes a reusable glass carrier for sheet-to-sheet processing of thin polymer substrates. Formation of the surface modification layer on the glass support produced a temporary bond with moderate adhesion between the thin polymer sheet and the support. Moderate adhesion is achieved by optimizing the contributions of van der Waals and covalent attraction energies to the total adhesion energy, which is controlled by adjusting the polar and non-polar surface energy components of the flakes and supports. This moderate bond is strong enough to withstand FPD processing (including wet ultrasonic, vacuum and thermal processes), and the polymer sheet remains debondable from the carrier by applying sufficient peel force. Debonding enables the removal of fabricated devices on thin polymer sheets and enables the reuse of the carrier, as the surface modification layer is <1 μm thick and easily removed in oxygen plasma.

Using a thin surface modification layer to create a moderate bond between the thin polymer sheet and the glass support provides the following benefits:

(1) The approximate 100-fold reduction in the amount of material used to bond thin polymer sheets and supports compared to commercial adhesives reduces the possibility of outgassing and pollutant adsorption and contamination of downstream processes.

(2) The highly cross-linked plasma polymer surface modification layer is non-volatile and insoluble, reducing the possibility of outgassing and process contamination.

(3) The surface modification layer is easily removed in oxygen plasma or downstream oxygen plasma at elevated temperature.

(4) The glass carrier can be reused because the surface modification layer is thin and easy to remove.

PEN and PET are the usual polymer substrates of choice in roll form that can be used in electronics manufacturing. They are chemically inert compared to most polymers, have low water absorption, low expansion, and are temperature resistant. However, their properties are not as good as glass. For example, for non-thermally stabilized PEN, the maximum temperature is 155°C, while for PET it is only 120°C. These temperatures are low compared to the >600°C use temperature of display glass suitable for pSi processing. For PEN, the thermal expansion is about 20ppm, as opposed to 3.5ppm for display glass. After 30 minutes at 150°C, the shrinkage at temperature was about 0.1%, which far exceeds the relaxation and compression of glass at much higher temperatures. These poor physical properties of polymeric substrates require process changes to deposit high quality devices with high yields. For example, silicon dioxide, silicon nitride, and amorphous silicon deposition temperatures must be lowered to stay within the confines of the polymer substrate.

The physical properties of the polymers described above also make bonding to rigid supports for sheet-to-sheet processing challenging. For example, thermal expansion of polymer sheets is typically 6 times higher than that of display glass. Despite having a small upper temperature limit, the thermal stresses are large enough to produce buckling and bowing and cause delamination when conventional bonding techniques are used. The use of high expansion glasses such as soda lime glass or higher expansion metal supports helps manage bowing issues, but these supports often have issues related to contamination, compatibility or roughness (heat transfer).

The surface energy of PEN and PET is also significantly lower than that of glass. As shown in Table 16 below, Glass exhibits a surface energy of approximately 77 mJ/m2 after SC1 chemistry and standard cleaning techniques. See Example 16e. In the absence of surface treatment, PEN and PET are non-polar and have a surface energy of 43-45 mJ/m2 (43-45 dyne/cm). See Table 15 below from "Remote Atmospheric-Pressure Plasma Activation of the Surfaces of Polyethylene Terephthalate and Polyethylene Naphthalate" by E. Gonzalez, II, MD Barankin, PC Guschl and RF Hicks Remote atmospheric pressure plasma activation of surfaces of ethylene glycol)" Table 2, Langmuir 2008 24(21), 12636-12643. Plasma cleaning treatment (for example by oxygen plasma) greatly increases the surface energy to 55-65 mJ/m2 (5-65 dyne/cm, "plasma") by adding reactive species. Additionally, UV ozone treatment or corona discharge can be used to clean polymers and briefly raise their surface energy. However, the surface energy decreases over time back to its previous value ("ageing").

For these surface energies (about 55-65 mJ/m2) of the polymer bonding surface, and about 77 mJ/m2 for the glass carrier bonding surface, the polymer sheet does not adhere well enough to the glass support to enable processing of structures on the sheet , but if first solidified on a glass support and then heated to a suitable temperature, the polymer cannot be peeled off from the glass support. Therefore, for initial bonding of PEN or PET to glass at room temperature, it was found to be advantageous to modify the surface energy of the glass support to closely match that of PEN or PET. Furthermore, the various surface modification layers described above were found to control the bonding energy, allowing the polymer layer to be detached from the glass support even after organic TFT processing cycles (including 1 hour of 120°C vacuum annealing and 1 minute post-bake step of 150°C).

By properly tuning the surface energy of the glass support by selecting an appropriate surface modification layer, sufficient wetting and adhesion strength can be achieved, making polymers (such as PEN or PET) and glass supports suitable for organic TFT processing (including 1 hour 120°C vacuum annealing and 1 minute 150°C post-bake step) to control the bonding while achieving the removability of the polymer and support after processing. The polymer sheet can be successfully removed from the carrier, i.e. the polymer sheet is controllably bonded to the carrier, even after the above processing, with transistors between the OTFT on the polymer sheet and the OTFT on the mask used to produce it There was no significant difference in geometry. The surface modification layer can be selected from a variety of materials and treatments indicated throughout this specification. Advantageously, the polymeric material can be plasma cleaned prior to bonding (to increase the polar component of its surface energy to facilitate initial bonding), but this is not necessary as the surface of the glass support can be greatly altered can, thereby achieving a suitable level of controlled adhesion to the polymer in its current state (ie, freshly received, freshly cleaned, or freshly aged). Based on the examples described above and those in Table 16 below, a surface energy range of about 36 mJ/m2 (Example 5g) to about 80 mJ/m2 (Example 5f) can be achieved on the glass carrier bonding surface.

Several methods of surface modification described above are suitable for bonding polymer sheets to glass carrier adhesives, including those formed from carbon sources, eg, from plasma polymerization of hydrocarbon gases. For example: plasma polymer films deposited from fluorocarbon gases (Examples 5a and 5g); plasma polymer films deposited from fluorocarbon gases and subsequently treated simultaneously with nitrogen and hydrogen (Example 5m); Plasmapolymer films deposited from fluorine-containing gases (Examples 6a-6j); Plasmapolymer films deposited from various mixtures of hydrocarbon, optionally nitrogen, and hydrogen gases (Examples 7a-g, 12j); Various fluorine-free gas deposition and subsequent nitrogen treatment of plasma polymer films (Examples 9a-9j), where these surface energies are useful for various states of cleaned and/or aged polymers; and from various A plasma polymer film deposited by a fluorine-free gas followed by sequential treatment with nitrogen and then hydrogen (Examples 10a-10p), or the case of treatment with dilute ammonia (Examples 8b, 8d), or subsequent treatment with N2-O2 Then with N2 treatment (Examples 11a, 11e), or with N2-O2 treatment (Examples 11f, 12c), they all work particularly well with plasma cleaned PEN. For polymers other than PET or PEN, other surface treatments may be appropriate, depending on the surface energy present on the polymer immediately prior to bonding, as it may be affected by the degree of cleaning and aging. It was found that the surface energy of the glass support, which approximately matches the surface energy of the polymer sheet, works well both in the initial bonding and the controlled bonding, so that the polymer sheet can be easily processed in the organic TFT type (including 1 hour of 120°C vacuum annealing and 1 minute post-bake step at 150°C) followed by debonding.

Furthermore, as follows, other formulations of the surface modification layer were explored for achieving the surface energy range of the polymer sheet surface energy such that the polymer sheet bonded to the glass support.

Surface modification layer formed by gas mixture

An example of the use of plasma polymerized films to tune the surface energy of, and/or control the type of polar bonds on, capping surface hydroxyl groups on a bonded surface is to deposit a surface from a mixture of source gases, including hydrocarbons, e.g., methane. Modified film. Deposition of surface modification layers can be performed at atmospheric or reduced pressure using plasma excitation such as DC or RF parallel plate, inductively coupled plasma (ICP), electron cyclotron resonance (ECR), downstream microwave or RF plasma. The plasma polymerized surface modification layer may be disposed on the carrier and/or the bonding surface of the foil. As described above with respect to the examples in Table 3, plasma polymerization produced layers of highly cross-linked material. Control of reaction conditions and source gases can be used to control the film thickness, density, and chemistry of the surface modification layer to tailor the functional groups to desired applications. By controlling the film properties, including the amount of surface hydroxyl groups covered, the surface energy of the support bonding surface can be tuned. The surface energy can be tuned to control the degree of bonding, ie to prevent permanent covalent bonding between the flakes and the support during subsequent processing to place films or structures on the flakes.

In the examples in Table 16 below, various conditions were used to deposit plasma polymerized films on glass supports. The glass carrier is made of (Aluminoborosilicate alkali-free display glass available from Corning Incorporated, Corning NY) Substrates manufactured. Prior to film deposition, clean the support using SC1 and/or SC2 chemistry and standard cleaning techniques. Films were deposited in a STS Multiplex PECVD apparatus (available from STPS, Newport, UK) in a triode electrode configuration with the carrier on the platen to which 50 watts of 380 kHz RF energy was applied , a (coil) nozzle is arranged on the platen, 300 watts of 13.5MHz RF energy is applied to it, the temperature of the platen is 200°C, and the gas flow rate through the nozzle is shown in Table 16 (the flow unit is standard cubic centimeters per minute, sccm). Thus, for example, the symbols in the "Surface Modification Layer Deposition Process" column of Table 16 for Example 16b are read as follows: In STS Multiplex PECVD equipment, at a platen temperature of 200°C, 200 sccm of H2, 50 sccm of CH4, and 20 sccm of C2F6, flowing together through the shower head into a chamber at a pressure of 300 mTorr; 300 W of 13.5 MHz RF energy is applied to the shower head, and 50 W of 380 kHz RF energy is applied to the platen on which the carrier is placed; and deposition The time is 120 seconds. The symbols in the surface treatment column of the remaining examples can be interpreted in a similar manner. The surface energy in mJ is calculated using the Wu model and the contact angle (CA) of three different test liquids, in this case water (W), hexadecane (HD) and diiodomethane (DIM) /m ² (millijoules per square meter). For surface energy, the polar (P) and dispersive (D) components and the sum (T) are shown. In addition, the thickness of the surface modification layer, in angstroms, "Th(A)" is also shown for these examples.

Example 16e is bare after cleaning with SC1 chemistry and standard cleaning techniques glass sheet. Example 16e shows that after cleaning, the surface energy of the glass is about 77 mJ/ ^m2 .

Examples 16a-16d show that a surface modifying layer can be deposited on a glass surface to modify its surface energy so that the surface of the glass can be tuned for a specific bonding application. The example in Table 16 is an example of a one-step process, as are the examples in Tables 6 and 7, for depositing a surface modification layer with the desired surface energy and polar groups.

Example 16a shows that the surface modification layer can be a plasma polymerized film deposited from a mixture of hydrogen and methane (hydrocarbon) gases. In these examples, the surface modification layer was deposited onto a cleaned glass support. Thus, it was shown that deposition of a surface modifying layer lowered the surface energy from about 77 ^mJ /m2 to about 49 mJ/ ^m2 , which is the range of typical polymer bonding surfaces.

Example 16b shows that the surface modification layer can be a plasma polymerized film deposited from a mixture of hydrogen, methane (hydrocarbon) and fluorine-containing gas (eg, C2F6, fluorocarbon). In these examples, the surface modification layer was deposited onto a cleaned glass substrate. Thus, it was shown that deposition of a surface modifying layer lowered the surface energy from about 77 ^mJ /m2 to about 37 mJ/ ^m2 , about the range of a typical polymer bonding surface. The surface energy achieved in Example 16b was lower than that achieved in Example 16a, showing that the addition of fluorine to the deposition gas can reduce the surface energy achieved by otherwise similar surface modified layer deposition conditions.

Example 16c shows that the surface modification layer can be a plasma polymerized film deposited from a mixture of hydrogen, methane (hydrocarbon) and nitrogen containing gas (eg, N2). In these examples, the surface modification layer was deposited onto a cleaned glass support. Thus, it was shown that the deposition of a surface modification layer reduced the surface energy from about 77 ^mJ /m2 to about 61 mJ/ ^m2 , which is the range for a typical polymer bonded surface treated with O2 plasma during polymer sheet cleaning. . The surface energy is also in a range suitable for bonding the thin glass sheet to the carrier.

Example 16d shows that the surface modification layer can be a plasma polymerized film deposited from a mixture of methane (hydrocarbon) and nitrogen containing gas (eg, NH3). In this example, a surface modifying layer was deposited onto a cleaned glass substrate. Thus, it was shown that deposition of a surface modifying layer lowered the surface energy from about 77 mJ/m ² to about 57 mJ/m ² , which is also about the range of a typical polymer bonding surface. Also, for some applications this may be suitable for bonding the carrier to the thin glass sheet.

The surface energies achieved by Examples 16c and 16d compared to that achieved by Example 16a show that the addition of nitrogen (N2 or NH3) to the deposition gas can increase the surface energy achieved by an otherwise similar deposition gas.

The surface energy obtained by the surface modification layer of Example 16b is lower than 50mJ/ ^m2 (considered suitable for controlled bonding of glass flakes to glass supports), but the surface energy is suitable for polymer bonding surface and glass bonding. Surface bonding. In addition, it should be noted that the surface modification layer produced by Examples 16c and 16d (formed by plasma polymerization of hydrocarbon (methane), optionally hydrogen-containing gas (H2) and nitrogen-containing gas (N2 or ammonia)) Surface energies are greater than about 50 mJ/m ² and thus, in some cases, may be suitable for bonding thin glass sheets to glass supports.

The sheet bonded to the carrier on which the surface modification layer according to the examples 16a-16d of Table 16 is arranged is made from (obtained from DuPont (DuPont)) Substrate made of Q65PEN with a thickness of 200 microns.

In the examples of Table 16, although the bonding surface on which the surface modifying layer is disposed is glass, this is not necessarily the case. Rather, the bonding surface may be other suitable materials having similar surface energies and properties to glass, eg silicon, polysilicon, single crystal silicon, ceramic, glass-ceramic, sapphire or quartz.

Plasma polymerized hydrocarbon polymer films can be deposited from methane and hydrogen (Example 16a), optionally with fluorocarbons (Example 16b), optionally with nitrogen (Example 16c), or optionally with ammonia (Example 16d ) additions in STS Multiplex CVD in triode mode. With fluorocarbons or nitrogen addition, surface energies as low as 37 mJ/m2 (Example 16b) and higher surface energies (about 61 mJ/m2, Example 16c) can be achieved. Surface energies between the levels of Examples 16b and 16c can also be achieved (i.e. about 49 mJ/m2 in Example 16a and about 57 mJ/m2 in Example 16d), demonstrating that based on deposition conditions (including deposition gas) The ability to adjust the surface energy of the surface modification layer.

As a counter-example, polymer films were deposited onto SC1 cleaned bare glass supports (Example 16e). However, the polymer sheet did not adhere well enough to the support to allow structural processing on the polymer sheet.

For organic TFT processing to be suitable, more than wetting and adhesive strength are required. The large difference in thermal expansion between the polymer film and the support is optimally managed by choosing a high expansion glass to minimize the difference in expansion, and by reducing the rate of the heating and cooling steps. The need for a smooth and clean substrate surface with minimal water uptake during processing can be accomplished by spin-coating and curing a thin layer of a suitable organic dielectric that simultaneously planarizes the surface and creates resistance to moisture and other contaminants. barrier.

Using a surface modification layer process to convert PEN( Q65, 200 µm thick, DuPont) bonded to glass carrier. Very good adhesion properties were found for the amorphous carbon layer deposited under the following conditions: 50CH4 200H2 300W 13.56MHz RF to showerhead, 50W 380kHz RF to 200°C platen, and 2 minute deposition time. The PEN was exposed to a UV-ozone cleaner for 5 minutes prior to bonding as this was found to improve adhesion. PEN was applied using a Teflon applicator. A ~150 nm thick cycloaliphatic epoxy layer was spin-coated and cured onto the PEN to smooth out surface defects. Organic gate insulators (OGIs) are photo-patternable cycloaliphatic epoxies.

A bottom-gate, bottom-contact organic thin film transistor array is formed through the following process. 100 nm of Al gate metal was deposited by sputtering in AJA and photolithographically patterned with Fuji 6512 photoresist, gates were patterned by wet etching in Type A Al etchant. The photoresist was removed by doing a 3 min room temperature PGMEA bath followed by an IPA/DI rinse (NMP based stripers are not compatible with epoxy layers). A second epoxy gate insulation layer was spin-coated on the patterned gate and cured. Ag S/D metal was sputtered 100 nm thick, patterned with Fuji 6512 lithography, and etched with a 1:1 mixture of Transene TFS:pH 10 buffer. Etching is challenging because the Ag etch rate is fast, but the dissolution of etch products is slow. Very good results were obtained by etching for 5s, removing the etch products with a spray of DI water, and repeating 4-5 times. Wetting of tetrathienocene-DPP copolymer (PTDPPTFT4) organic semiconductor (OSC) layers is challenging. OSC adhesion was promoted by HMDS treatment in a YES oven at 120 °C. OSC polymer was dissolved in 6 parts decalin:4 parts toluene at a concentration of 5 mg/mL. OSCs were spin-coated in a Laurel spin coater with manual dispensing, 20 sec rest, 500 rpm for 30 sec, 1000 rpm for 60 sec. The OSC film was soft-baked on a hot plate at 90°C for 2 minutes, and annealed in a Salvis oven under rough vacuum at 120°C for 1 hour to remove residual decalin. Using a brief 5 s O2 plasma in Branson to create adhesion, a third OGI layer was spin-coated on the OSC and directly photolithographically patterned with a 2.5 s exposure, 1 min rest, and post-bake at 150 °C Bake for 1 minute. After a 1 min rest, active patterns were tracked in PGMEA for 1 min, followed by IPA and DI rinses. A dry etch was performed using an Unaxis 790RIE (using 30sccm O2 10sccm Ar 20sccm CHF3 50mTorr 200W 15s) to pattern the active and expose the gate metal. The performance of 75/75um TFTs is summarized in the table shown in Figure 18, which shows that for a typical transistor (with 75 micron channel width and 75 micron channel length, bottom gate, bottom contact organic thin film transistor) leakage current vs gate voltage and performance. PEN is easily debonded by using a blade to initiate cracking followed by peeling. Successful removal of the polymer sheet from the carrier, even after the above processing, showed no significant difference in transistor geometry between the OTFT on the polymer sheet and the OTFT on the mask used to produce it.

Also successfully in PEN sheet ( Q65, a 200 micron thick sheet from DuPont) was subjected to the process described above to form a bottom-gate bottom-contact organic thin film transistor array, the PEN sheet being controlled bonded to the A support made of glass (alkali-containing chemically strengthenable cover glass, available from Corning Incorporated, Corning, NY) with a suitable surface modification layer selected from those described above.

As noted above, the polymer itself can be the substrate upon which other devices are fabricated. Alternatively, the polymer can be a polymer surface on a composite substrate (eg, a glass/polymer composite). In this case, the polymer surface of the glass/polymer composite would face the carrier and would bond thereto, as described above, while the glass surface of the glass/polymer composite would be exposed as the surface on which electronics or surfaces of other structures. After an electronic component or other structure has been fabricated on the glass surface of the glass/polymer composite, the polymer surface of the composite can be stripped from the surface modifying layer on the support. This embodiment may be advantageous when the glass layer in the glass/polymer composite becomes particularly thin, such as ≤50 microns, ≤40 microns, ≤30 microns, ≤20 microns, ≤10 microns, or ≤5 microns in thickness of. In this case, the polymer portion of the glass/polymer composite does not merely act as a bonding surface to allow the composite to attach to the carrier, it also provides some handling advantages to the composite when it is not on the carrier.

in conclusion

It should be emphasized that the above-described embodiments of the present invention, especially any "preferred" embodiments, are merely examples of possible implementations, merely for a clear understanding of the principles of the invention. Many changes and modifications may be made to the above-described embodiments of the invention without departing significantly from the spirit and principles of the invention. All such changes and modifications are intended to be included within the scope of this and the present invention and protected by the following claims.

For example, while many embodiments have shown and described surface modification layer 30 as being formed on carrier 10 , it may alternatively or additionally be formed on sheet 20 . That is, the materials described in the examples of Tables 3-12 and 16 may be applied to the faces of the carrier 10 and/or sheet 20 that are to be bonded together, as appropriate.

Furthermore, while some surface modification layers 30 are described as controlling the bond strength to allow removal of the flakes 20 from the carrier 10 even after the article 2 has been processed at temperatures of 400°C (or 600°C), it is of course also possible to remove the flakes 20 after the article has been passed Article 2 is processed at those temperatures at which the specific test is lower and still achieves the same ability to remove flakes 20 from carrier 10 without causing damage to flakes 20 or carrier 10 .

Furthermore, while the concept of controlled bonding is described here using supports and sheets, in some cases they are applicable to controlled bonding between thicker sheets of glass, ceramic, or glass-ceramic, where sheets ( or parts thereof) are separated from each other.

Furthermore, while it is described herein that the controlled bonding concept can be applied to glass supports and glass flakes, supports can also be made of other materials (eg, ceramics, glass-ceramics, or metals). Similarly, the sheets in controlled bonding to the carrier may be made of other materials such as ceramics or glass-ceramics.

Similarly, while the surface-modified layers described above in Examples 3 and 5-12 were formed by plasma polymerization, other techniques are possible, such as by hot vapor UV activation of substances in gas, or wet etching.

In addition, although the plasma-polymerized carbonaceous surface-modified layers of Examples 6-12 were formed using methane as the polymer-forming gas, other carbon-containing source materials are also possible. For example, the carbon-containing source can include at least one of the following: 1) hydrocarbons (alkanes, alkenes, alkynes, or aromatics. Alkanes include, but are not limited to: methane, ethane, propane, and butane; alkenes include, but are not limited to: ethylene , propylene and butene; alkynes include but not limited to: acetylene, methylacetylene, ethylacetylene and dimethylacetylene; aromatic hydrocarbons include but not limited to: benzene, toluene, xylene, ethylbenzene; 2) alcohols (including: methanol, ethanol, propanol); 3) aldehydes or ketones (including: formaldehyde, acetaldehyde and acetone); 4) amines (including: methylamine, dimethylamine, trimethylamine and ethylamine); 5 ) organic acids (including: formic acid and acetic acid); 6) nitriles (including: acetonitrile); 7) CO; and 8) CO2. Alternatively, the carbon-containing source may include one or more of: 1) saturated or unsaturated hydrocarbons; or 2) carbon-containing saturated or unsaturated hydrocarbons or 3) oxygen-containing saturated or unsaturated hydrocarbons; or 4) CO or CO2. Some typical carbonaceous raw materials in general include carbonaceous gases such as methane, ethane, propane, butane, ethylene, propylene, propyne, acetylene, MAPP, CO, and CO2.

In addition, although the polar groups used to treat the surface modification layer in Examples 5 and 8-12 to increase its surface energy or to form the surface modification layer itself in Examples 7, 16c, and 16d are nitrogen and Oxygen, but other polar groups are also possible, eg sulfur and/or phosphorus.

In addition, although N2 and NH3 are used as nitrogen-containing gases, other nitrogen-containing materials are also possible, such as hydrazine, N2O, NO, N2O4, methylamine, dimethylamine, trimethylamine and ethylamine, acetonitrile.

In addition, although the oxygen-containing gases used are N2-O2 and O2, other oxygen-containing gases such as O3, H2O, methanol, ethanol, propanol, N2O, NO, and N2O4 may also be used.

As can be seen from the examples described herein, surface modification layers (including those subsequently treated) can be achieved from about 1 nm (Example 16b) or 2 nm (Example 3, 4) to about 10 nm (Example 12c). , 8.8nm) thickness. Furthermore, thicker surface modification layers are also possible, as explained with respect to FIG. 15 . However, as the thickness becomes greater than about 70 nm, the surface modification layer begins to become translucent, which may be undesirable for applications that benefit from optical clarity.

The various concepts described above in accordance with the application may be combined with other concepts in any and all of the different combinations. For example, various concepts can be combined according to the following aspects.

According to a first aspect, there is provided a method of controllably bonding a substrate to a carrier, the method comprising:

obtaining a substrate having a polymer bonding surface having a first surface energy;

obtaining a carrier having a glass bonding surface having a second surface energy;

depositing a surface modifying layer onto the glass bonding surface, thereby reducing the surface energy of the glass bonding surface; and

The polymer bonding surface is bonded to the glass bonding surface via the surface modification layer, wherein, after being subjected to vacuum annealing in an environment at a temperature of 120° C. for 1 hour, the substrate can be removed from the The carrier is nondestructively debonded.

According to a second aspect, there is provided the method of the first aspect, wherein the deposition of the surface modification layer is performed by one of the following:

Plasma polymerization of carbonaceous gases;

Plasma polymerization of hydrocarbon-containing gases;

Plasma polymerization of hydrocarbon- and fluorocarbon-containing gases;

Plasma polymerization of hydrocarbon- and hydrogen-containing gases;

plasma polymerization of a hydrocarbon-containing gas to form a layer, after which the layer is treated with a nitrogen-containing gas;

Plasma polymerization of a hydrocarbon-containing gas to form a layer, which is then sequentially treated with two separate gases, one containing nitrogen and the other containing hydrogen;

plasma polymerization of a hydrocarbon-containing gas to form a layer, which is then sequentially treated with two separate gases, one gas containing nitrogen and oxygen and the other gas containing nitrogen;

plasma polymerization of a hydrocarbon-containing gas to form a layer, after which the layer is treated with a nitrogen- and oxygen-containing gas;

Plasma polymerization of hydrocarbon-, nitrogen-, and hydrogen-containing gases;

plasma polymerization of a hydrocarbon-containing gas and a hydrogen-containing gas to form a layer, after which the layer is treated with a nitrogen-containing gas;

Plasma polymerization of fluorocarbon-containing gases;

Plasma polymerization of fluorocarbon-containing gases and hydrogen-containing gases; and

A plasma of a fluorocarbon-containing gas polymerizes to form a layer, which is then treated simultaneously with a nitrogen-containing gas and a hydrogen-containing gas.

According to a third aspect, there is provided the method of the first aspect, wherein said surface modification layer is deposited by plasma polymerization of methane, ammonia and hydrogen.

According to a fourth aspect, there is provided the method of the second aspect, wherein the carbon-containing gas includes at least one of the following: hydrocarbons, alkanes, alkenes, alkynes or aromatic hydrocarbons.

According to a fifth aspect, the method of the second aspect is provided, wherein the carbon-containing gas comprises at least one of the following: methane, ethane, propane, butane, ethylene, propylene, propyne, acetylene, CO and CO2 .

According to a sixth aspect, there is provided the method of any one of aspects 2, 4, 5, wherein when a hydrogen-containing gas is used, the hydrogen-containing gas comprises H2, and wherein, when a nitrogen-containing gas is used, The nitrogen-containing gas includes at least one of ammonia, N2, hydrazine, N2O, NO, N2O4, methylamine, dimethylamine, trimethylamine, ethylamine and acetonitrile.

According to a seventh aspect, there is provided the method of any one of aspects 2, 4-6, wherein, when a hydrogen-containing gas is used, the hydrogen-containing gas comprises H2, and wherein, when an oxygen-containing gas is used, The oxygen-containing gas includes at least one of O2, O3, H2O, methanol, ethanol, propanol, N2O, NO and N2O4.

According to an eighth aspect, there is provided the method of any one of the 1-7 aspects, wherein the surface modification layer has a thickness of 1-70 nm.

According to a ninth aspect, there is provided the method of any one of the 1-7 aspects, wherein the surface modification layer has a thickness of 2-10 nm.

According to a tenth aspect, there is provided the method of any one of aspects 1-9, said method further comprising cleaning said polymer bonding surface, thereby providing said first surface energy.

According to an eleventh aspect, there is provided the method of the tenth aspect, wherein the cleaning comprises one of the following: oxygen plasma cleaning, UV ozone treatment and corona discharge.

According to a twelfth aspect, there is provided the method of any one of aspects 1-11, wherein the substrate is a composite comprising a polymer and glass.

According to a thirteenth aspect, there is provided the method of any one of aspects 1-12, wherein said glass bonding surface has an average surface roughness Ra < 1 nm prior to depositing said surface modification layer.

According to a fourteenth aspect, there is provided the method of any one of aspects 1-13, wherein the thickness of the substrate is ≤ 300 microns.

According to a fifteenth aspect, there is provided the method of any one of the first to fourteenth aspects, wherein the thickness of the carrier is 200 microns to 3 mm.

According to a sixteenth aspect, there is provided an article comprising:

Substrates with polymeric bonding surfaces;

a carrier with a glass bonding surface;

A plasma polymerized surface modification layer that releasably bonds the polymer bonding surface to the glass bonding surface.

According to a seventeenth aspect, there is provided the article of the sixteenth aspect, wherein the thickness of the surface modification layer is 1-70 nm.

According to an eighteenth aspect, there is provided the article of the sixteenth aspect, wherein the surface modification layer has a thickness of 2-10 nm.

According to a nineteenth aspect, there is provided the article of any one of aspects 16-18, said surface modification layer comprising at least one of the following:

plasma polymerized hydrocarbons; and

Plasma polymerized fluorocarbons.

According to a 20th aspect, there is provided the article of any one of aspects 16-19, wherein the substrate is a composite comprising a polymer and glass.

According to a 21st aspect, there is provided the article of any one of the 16th to 20th aspects, wherein, in the absence of the surface modifying layer disposed thereon, the average surface roughness Ra of the glass bonding surface is ≤1nm.

According to a 22nd aspect, there is provided the article of any one of the 16th to 20th aspects, wherein, in the absence of the surface modifying layer disposed thereon, the average surface roughness Ra of the glass bonding surface is ≤0.2nm.

According to a 23rd aspect, there is provided the article of any one of the 16th to 22nd aspects, wherein the substrate has a thickness < 300 microns.

According to a 24th aspect, there is provided the article according to any one of the 16th to 23rd aspects, wherein the thickness of the carrier is 200 microns to 3 mm.

According to aspect A, there is provided a glass article comprising:

a carrier having a carrier bonding surface;

A surface modifying layer disposed on the carrier bonding surface, wherein the surface modifying layer is configured such that the carrier bonding surface and the glass sheet bonding surface are bonded with the surface modifying layer therebetween, upon subjecting the article to a temperature cycle of Afterwards (the temperature cycling was carried out by heating in the chamber, cycling from room temperature to 600°C at a rate of 9.2°C per minute, maintaining the temperature at 600°C for 10 minutes, and then cooling to 300°C at 1°C per minute °C, and then remove the article from the chamber and allow the article to cool to room temperature), the carrier and the sheet do not separate from each other, (if one is lifted while the other is subjected to gravitational forces), and there is no change from the surface during the temperature cycle. Degassing of the non-reactive layer and separation of the sheet from the support can occur (without breaking the thinner of the support and the sheet into two or more pieces).

According to aspect B, there is provided a glass article comprising:

a carrier having a carrier bonding surface;

A sheet having a sheet-bonding surface;

a surface modification layer disposed on one of said carrier bonding surface and said sheet bonding surface;

When the carrier bonding surface and the sheet bonding surface are bonded with the surface modifying layer therebetween, wherein the surface allowing the sheet to be bonded to the carrier can have properties that after subjecting the article to a temperature cycle (the temperature cycle This was done by heating in the chamber, cycling from room temperature to 600°C at a rate of 9.2°C per minute, holding the temperature at 600°C for 10 minutes, and then cooling at 1°C per minute to 300°C, and then from chamber and allow the article to cool to room temperature), the carrier and sheet do not separate from each other (if one is lifted while the other is subjected to gravitational forces), and there is no delamination from the surface modification layer during temperature cycling. gas, and the sheet can separate from the support (the thinner of the support and the sheet without breaking into two or more pieces).

According to aspect C, there is provided the glass article of any one of aspects A or B, wherein the surface modification layer has a thickness of 0.1-100 nm.

According to aspect D, there is provided the glass article of any one of aspects A or B, wherein the thickness of the surface modification layer is 0.1-10 nm.

According to aspect E, there is provided the glass article of any one of aspects A or B, wherein the surface modification layer has a thickness of 0.1-2 nm.

According to aspect F there is provided a glass article according to any one of aspects A to E or 1-24, wherein the support is a glass comprising an alkali-free aluminosilicate or borosilicate or aluminoborosilicate Salt, glass with arsenic and antimony levels ≤ 0.05% by weight, respectively.

According to aspect G, there is provided the glass article of any one of aspects A to F or 1-24, wherein the carrier and the sheet each have dimensions of 100mm x 100mm or more.

Claims (14)

1., by a method for base material Yu the controlled bonding of carrier, described method includes:

Obtaining the base material with polymer bonding surface, described polymer bonding surface has first surface energy；

Obtaining the carrier with glassy bond surface, described glassy bond surface has second surface energy；

Surface modification is deposited on described glassy bond surface, thus reduces the surface energy on described glassy bond surface；With And

Described polymer bonding surface is bondd via described surface reforming layer with described glassy bond surface, wherein, in temperature Degree be the environment of 120 DEG C stands vacuum annealing in 1 hour after, described base material is can to tie from described carrier non-damaging unsticking 's.

2. the method for claim 1, it is characterised in that deposit described surface reforming layer by following a kind of mode:

The plasma polymerization of carbonaceous gas；

The plasma polymerization of gas containing hydrocarbon；

Hydrocarbonaceous and the plasma polymerization of hydrofluorocarbons gas；

Hydrocarbonaceous and the plasma polymerization of hydrogen-containing gas；

Described layer, with cambium layer, is processed by the plasma polymerization of gas containing hydrocarbon afterwards with nitrogenous gas；

Described layer, with cambium layer, is processed successively by the plasma polymerization of gas containing hydrocarbon afterwards with two kinds of separate gases, One of which gas is nitrogenous, and another kind of gas is hydrogeneous；

Described layer, with cambium layer, is located successively by the plasma polymerization body of gas containing hydrocarbon afterwards with two kinds of separate gases Reason, one of which gas is nitrogenous and oxygen, and another kind of gas is nitrogenous；

Described layer, with cambium layer, is processed by the plasma polymerization of gas containing hydrocarbon afterwards with nitrogenous and oxygen-containing gas；

The plasma polymerization of gas containing hydrocarbon, nitrogenous gas and hydrogen-containing gas；

Described layer, with cambium layer, is processed by the plasma polymerization of gas containing hydrocarbon and hydrogen-containing gas afterwards with nitrogenous gas；

The plasma polymerization of hydrofluorocarbons gas；

Hydrofluorocarbons gas and the plasma polymerization of hydrogen-containing gas；And

Described layer, with cambium layer, is entered by the plasma polymerization body of hydrofluorocarbons gas afterwards with nitrogenous gas and hydrogen-containing gas simultaneously Row processes.

3. the method for claim 1, it is characterised in that sunk by the plasma polymerization of methane, ammonia and hydrogen Long-pending described surface reforming layer.

4. the method for claim 1, it is characterised in that the thickness of described surface reforming layer is 1-70nm.

5. the method for claim 1, described method also includes:

Described polymer bonding surface is cleaned, thus described first surface energy is provided.

6. the method for claim 1, it is characterised in that described base material is the complex comprising polymer and glass.

7. the method for claim 1, it is characterised in that before depositing described surface reforming layer, described glassy bond Average surface roughness Ra≤the 1nm on surface.

8. the method for claim 1, it is characterised in that thickness≤300 micron of described base material.

9. goods, described goods include:

There is the base material on polymer bonding surface；

There is the carrier on glassy bond surface；

The surface reforming layer of plasma polymerization, it makes described polymer bonding surface can depart from described glassy bond surface Ground bonding.

10. goods as claimed in claim 9, it is characterised in that the thickness of described surface reforming layer is 1-70nm.

11. goods as claimed in claim 9, it is characterised in that described surface reforming layer include following at least one:

The hydrocarbon of plasma polymerization；And

The hydrofluorocarbons of plasma polymerization.

12. goods as claimed in claim 9, it is characterised in that described base material is the complex comprising polymer and glass.

13. goods as claimed in claim 9, it is characterised in that in the case of the most not arranging described surface reforming layer, Average surface roughness Ra≤the 1nm on described glassy bond surface.

14. goods as claimed in claim 9, it is characterised in that thickness≤300 micron of described base material.