TWI518027B - Large area nanopattering method and apparatus - Google Patents

Description

Large area nano patterning method and equipment

Embodiments of the present invention are directed to nanopatterning methods that can be used to pattern large area substrates or substrates such as films that are sold as roll articles. Other embodiments of the invention relate to apparatus that can be used to pattern substrates and can be used to perform method embodiments (including method embodiments of the type described).

This section describes the subject matter of the background matter related to the disclosed embodiments of the present invention. The Applicant has no intention, whether express or implied, to make the background art discussed in this section legally constitute a prior art.

Nanostructured is a must for many of today's applications and industries, as well as for new technologies that are evolving. For current applications in areas such as solar cells and LEDs, and in next generation data storage devices, which are by way of example and not limitation, efficiency improvements can be achieved.

Nanostructured substrates can be fabricated using, for example, electron beam direct writing, deep UV lithography, nanosphere lithography, nanoimprint lithography, near-field phase shift lithography, and plasmonic lithography. .

Nano Imprint Lithography (NIL) establishes a pattern by mechanical deformation and subsequent processing of an imprint resist. Typically, the embossing resist is a monomer or polymer formulation that is hardened by heat or UV light during embossing. There are many variations in NIL. However, two of the processes seem to be the most important. It is Thermoplastic NanoImprint Lithography (TNIL) and Step and Flash NanoImprint Lithography (SFIL).

TNIL is the earliest and most mature nanoimprint lithography. In a standard TNIL process, a thin embossed resist layer (a thermoplastic polymer) is spin coated onto the same substrate. Next, a mold having a predefined topographic pattern is brought into contact with the print and pressed against the sample at a given pressure. When the thermoplastic polymer is heated above the glass transition temperature, the pattern on the mold is pressed into the thermoplastic polymer film melt. After the sample with the pressed mold is cooled, the mold is separated from the sample and the embossing resist is left on the surface of the sample substrate. The pattern does not pass through the embossing resist, and the residual thickness of the thermoplastic polymer film that is ultimately altered is on the surface of the sample substrate. A pattern transfer process, such as reactive ion etching, can be used to transfer the pattern in the resist to the underlying substrate. Variations in the residual thickness of the unaltered thermoplastic polymer film can cause problems in the uniformity and optimization of the etching process used to transfer the pattern to the substrate.

In the SFIL process, a UV hardenable liquid resist is applied to the sample substrate and the mold is made of a permeable substrate such as molten alumina. After the mold and the sample substrate are pressed together, the resist is hardened by UV light and becomes solid. After the mold is separated from the hardened resist material, a pattern similar to that used in TNIL can be used to transfer the pattern to the underlying substrate. Both the SFIL and TNIL processes have many challenges, including stencil lifetime, yield rate, embossed layer tolerance, and critical dimension control during transfer of the pattern to the underlying substrate. The residual unembossed layer, which remains after the imprint process, requires an additional etching step prior to the main pattern transfer etch. Due to the problem of maintaining a uniform pressure over a large area, a single field NIL has difficulty controlling the uniformity of the replicated pattern over a large area substrate. A step and repeat method can potentially cover a large area, but the microstructure formed in each step is independent of the other steps and forms a seamless micro or nano structure over a large area without stitching A problem. A braiding error can occur when repeated pattern shifts are not properly aligned.

If a uniformly patterned roll surface is available, a roll-to-roll process is possible. In Japanese Unexamined Patent Publication No. 59200419A (published on November 13, 1984, entitled "Large Area Exposure Apparatus"), Toshio Aoki et al. describe the application of a cylindrical drum that can be rotated and displaced. The cylindrical drum has an internal light source and a patterned reticle material film attached to the outside of the cylindrical drum. A film that penetrates the heat reflective material is anchored inside the drum. a substrate having an aluminum film on its surface and a photoresist covering the aluminum film is in contact with the patterned mask of the drum surface, and the developing light is passed through the mask to cover the surface of the aluminum film Photoreceptor imaging. Next, the photoresist is developed to provide a developed photoresist. The patterned photoresist is then used as an etch mask for the aluminum film on the substrate.

There is no description of the type of material used as a photoresist on the surface of a photomask film or an aluminum film. A high pressure mercury lamp source (500 W) was used to develop a photoresist covering the aluminum film. A glass substrate having a thickness of about 210 mm (8.3 in.) x 150 mm (5.9 in.) and a thickness of about 0.2 mm (0.008 in.) was produced using a cylindrical drum pattern transfer device. The feature size of the pattern transferred using this technique is about 500 μm ² , which is obviously a square having a size of about 22.2 μm × 22.2 μm. This feature size is based on the approximate pixel size of an LCD display when the patent application was filed in 1984. The reticle film outside the cylindrical drum is said to last for about 140,000 pattern transfers. The contact lithography program used by Toshio Aoki et al. cannot produce sub-micron features.

Tapio Makela et al. at VTT (a technical research center in Finland) has published information on custom-made laboratory-scale roll-to-roll embossing tools that can be manufactured with high yields. Submicron structure. Hitachi and other companies have developed sheet- or roll-to-roll prototype NIL machines and have demonstrated the ability to handle sheets of 15 meter length. The goal has been to create a continuous imprint process using a die cast (nickel plated mold) to imprint polystyrene sheets for large geometry applications (eg for use in fuel cells, batteries and possibly displays). film). Currently, prototype tools cannot supply the desired output. In addition, for embossed surfaces, there is a need to improve reliability and repeatability. Toshiba has also published information on roll-to-roll UV imprinting tools that are said to produce sub-micron feature sizes.

Nanoimprint lithography, including roll-to-roll NIL, still has to overcome many challenges. Incomplete negative pattern filling and shrinkage of polymeric materials can create defects. The difference in coefficient of thermal expansion between the mold and the substrate causes lateral stretching, and the stretching is concentrated at the corners of the pattern. During the mold release step, stretching can cause defects and can cause cracking defects at the base of the pattern. Furthermore, for a uniformly etched pattern in a large area substrate below the embossed resist layer, the uneven thickness of the remaining unembossed layer, which remains after the embossing process, is particularly detrimental.

Soft lithography is an alternative to photolithography for micron and nanofabrication methods. This technology is about replica molding of self-assembled monolayers. In soft lithography, a printed article having a patterned relief structure on its surface is used to create patterns and structures having feature sizes between 30 mm and 100 nm. The most potential soft lithography technology is the use of self-assembled monolayers (SAMS) microcontact printing (μCP). The basic process of μCP includes: 1. A polydimethylsiloxane (PDMS) mold is immersed in a solution of a specific material in which a particular material can form a self-assembled monolayers (SAMS). Such specific materials may be referred to as inks. A specific material will adhere to the raised pattern on the main surface of the PDMS. 2. The PDMS mold (where the surface of the coated material faces down) is in contact with the surface of the substrate to which the metal (such as gold or silver) is coated, so that only the pattern on the surface of the PDMS mold and the substrate to which the metal is coated contact. 3. The specific material forms a chemical bond with the metal, so that after removal of the PDMS mold, only the particular material on the surface of the raised pattern remains on the surface of the metal being coated. The particular material forms a SAM on the metal coated substrate that extends about 1-2 nm above the metal coated substrate (just like the ink on the paper). 4. The PDMS mold is removed from the metal coated substrate leaving a patterned SAM on the metal coated surface.

The most preferred specific material to form a SAM on the surface to which gold or silver is coated is an alkanethiolate. When the surface of the substrate contains a hydroxyl end portion such as Si/SiO ₂ , Al/Al ₂ O ₃ , glass, mica, and a plasma-treated polymer, an alkylsiloxane can function well as a specific material. With regard to alkyl mercaptans, hexadecanethiol appears to be the most reproducible process on the thin (10-200 nm thick) gold or silver film that is evaporated. While these are the best known materials for patterning, gold and silver are not compatible with germanium-based microelectronic components, although electrodes or wires containing gold or silver may be used. At present, the μCP for SAM on the surface of Si/SiO ₂ is not as easy to handle as the μCP for the SAM of alkylthiol on gold or silver. The SAM of helium on Si/SiO ₂ often provides a messy SAM and in some cases produces a sub-monolayer or multiple layers. Finally, the patterned mold used in μCP is a flat "stamp" surface, and reproduction over large areas and reliable printing requires not only very precise braiding of the printed pattern from the mold, but also Constant prints utilize the wetting of specific materials formed by SAM, which is problematic.

Some new optical lithography techniques based on near field evanescent effects have demonstrated the advantages of printing a sub-100 nm structure, albeit only on a small area. Near-field shift lithography (NFPSL) involves exposure of a photoresist layer to ultraviolet light, wherein the UV light passes through an elastic phase mask, and the mask is attached to the The photoresist is conformally contacted. Contacting a resilient phase mask with a thin photoresist layer causes the photoresist to "wet" the contact surface of the mask. When the mask is in contact with the photoresist, the UV light is passed through the mask to expose the light intensity distribution developed by the photoresist on the surface of the mask. In the case of a mask having a relief depth designed to adjust the phase of the transmitted light to π, a local zero intensity occurs at the stepped edge of the relief. When a positive photoresist is used, exposure through such a mask and subsequent development produces a photoresist line having a width equal to the characteristic width of zero intensity. For a combination of 365 nm (near UV) light and a conventional photoresist, the zero intensity width is about 100 nm. The PDMS mask can be used to form a conformal atomic scale contact with a flat solid photoresist layer. Once contacted, this contact is automatically established without application of pressure. The general adhesion forces guide the process and provide a simple and convenient way to align the mask with angles and positions orthogonal to the direction of the photoresist surface to establish good contact. There is no physical gap relative to the photoresist. PDMS is permeable to UV light having a wavelength greater than 300 nm. The light from the mercury lamp (the main spectral line is at 355-365 nm) is passed through PDMS and the PDMS is in contact with a photoresist layer, exposing the intensity distribution of the photoresist formed on the mask.

In the 32nd International Conference on Micron and Nano Engineering in 2006, Yasuhisa Inao described a step developed by Canon in a briefing entitled "Near-Field Lighography as a prototype nano-fabrication tool". Repeated near-field nano lithography. Near-field lithography (NFL) is used, where the closer the mask to the photoresist (one of which is to be transferred to the photoresist), the better. The initial distance between the mask and the wafer substrate was set at about 50 μm. This patterning technique is described as a "three-layer resist process" using a very thin photoresist. A pattern transfer mask is attached to the bottom of a pressure chamber and pressurized to achieve "good physical contact" between the mask and the wafer surface. The mask is "deformed to match the wafer." The initial 50 [mu]m distance between the mask and the wafer is said to be used to allow the mask to be moved to another location for exposure and patterning greater than 5 mm x 5 mm area. The patterning system utilizes i-line (365 nm) radiation from a mercury lamp as a light source. Through such a stepping and repeating method, patterning of a 4-inch wafer having a structure of less than 50 nm can be successfully achieved.

In an article entitled "Large-area patterning of 50 nm structures on flexible substrates using near-field 193 nm radiation" on pages 78-81 of JVST B 21 (2002), Kunz et al. applied a near-field phase shift mask. The nano-shadowing of the lithography to the elastic sheet (polyimine film), wherein the near-field phase shift mask lithography is exposed using a hard fused silica mask and a deep UV wavelength. In a follow-up article entitled "Experimental and computational studies of phase shift lithography with binary elastomeric masks" on pages 828-835 of JVST B 24(2) (2006), Maria et al. proposed a phase-shifted photolithography technique. Experimental and computational studies in which the phase-shifted photolithography technique uses a binary elastic phase mask in conformal contact with the photoresist layer. This task introduces an optimum mask that is formed by casting and hardening a prepolymer into an elastic polydimethyl siloxane to abut a non-isotropically etched single crystal 矽 structure on SiO ₂ /Si. . The authors report the ability to use PDMS phase masks to form resist features throughout the geometry of the embossing on the mask.

U.S. Patent No. 6,753,131, to Rogers et al., issued June 22, 2004, to "Transparent Elastomeric, Contact-Mode Photolithography Mask, Sensor, and Wavefront Engineering Element," describes a contact mode photolithographic mask Wherein the contact mode photolithographic mask comprises a diffractive surface having a plurality of recesses and protrusions. The protrusion is in contact with the surface of the positive photoresist and the surface is exposed to electromagnetic radiation via a phase shift mask. Since the radiation passes through the recess relative to the protrusion, the phase shift is substantially complete. The minimum value of the electromagnetic radiation intensity is thereby generated at the boundary between the convex portion and the concave portion. The elastic mask is well conformed to the photoresist surface, and subsequent photoresist development, a feature of less than 100 nm can be obtained. (Abstract) In one embodiment, the reflector is used outside of the substrate and the contact mask so that the radiation will be returned to a desired position in the displacement phase. In another embodiment, the substrate can be formed to have a shape that can cause a phase shift mask to affect the phase shift mask behavior during exposure.

U.S. Patent Publication No. US 2006/0286488, filed on Jan. 2, 2006, to the entire disclosure of the entire disclosure of the entire disclosure of A method on the surface of a substrate. A conformal elastic phase mask can be used to create a 3-D structure that is capable of conformal contact with a radiation sensitive material that undergoes light processing (to produce a 3-D structure). The 3-D structure does not have to extend completely through this radiation sensitive material. (Summary)

Near Field Surface Plasmon Lithography (NFSPL) utilizes near-field intensification to induce photochemical or photophysical changes to produce nanostructures. The primary near-field technique is based on local field enhancement around the metal nanostructure as it is illuminated at the surface plasmon resonance frequency. Electro-plasma printing involves the use of evanescent waves guided through a plasmonics of a metal nanostructure to produce photochemical and photophysical changes in a layer below the metal structure. In particular, visible exposure (λ = 410 nm) of a silver nanoparticle of a film adjacent to a g-line photoresist (AZ-813, available from AZ-Electronic Materials, MicroChemicals, Ulm, Germany) can be selectively produced with a diameter less than λ/20 exposure area. In an article entitled "Plasmonic Nanolithography" on pages 1085-1088 of Nanoletters V4, N6 (2004), W. Srituravanich et al. describe the use of near-UV light (λ = 230 nm - 350 nm) for use in metal substrates. The SPs are intensified to enhance the transmission of periodic perforations through the sub-wavelength, which has an effective shorter wavelength than the wavelength of the intensified light. A plasmonic mask designed for lithography in the UV range consists of an aluminum layer (which is perforated with a periodic array of periodic holes) and two surrounding dielectric layers (one on each side). Aluminum is chosen because it can intensify SPs in the UV range. Quartz is used as a curtain support substrate with a polymethyl methacrylate interstitial layer, which acts as an adhesive for aluminum foil and as a dielectric between aluminum and quartz. quality. Polymethyl methacrylate (PMMA) is used in combination with quartz because of their penetration into UV light at the exposure wavelength (i line at 365 nm) and comparable dielectric constant (quartz and PMMA are 2.18 each) 2.30). Using a 635 nm wavelength of exposure radiation, a sub-100 nm dot array pattern of 170 nm period has been successfully produced. Obviously, the total area of the patterning is about 5 μm × 5 μm, and the scale-up problem has not been discussed in this study.

It seems that the imprint method (hot or UV hardening) or the use of soft lithography printed with SAM material is not a highly manufacturable process. In general, the imprint method produces deformation of the substrate material due to shrinkage of the pattern features of the heat treatment (such as thermal NIL) or polymer hardening (UV-cured polymer features). Furthermore, due to the pressure (hard contact) applied between the print and the substrate, defects are virtually unavoidable and the print has a limited life. Soft lithography has the advantage that it is a printing technique that does not contain heat and stress. However, the use of SAM as an "ink" for sub-100 nm patterns is problematic due to drift of molecules above the surface, and coating over large areas has not been experimentally confirmed.

Embodiments of the present invention based on nano large area substrates of about 200mm ² to about adapted 1,000,000mm ² (by way of example, and not limitation) of the patterning methods and apparatus. In some examples, the substrate can be a film having a given width and an undefined length that is sold on a reel. The nanopatterning technique utilizes near-field UV photolithography in which the mask used to pattern the substrate is in dynamic contact with the substrate or in very close proximity (less than 100 nm in the evanescent field) of the substrate. Near-field photo lithography can include a phase shift mask or surface plasmonic technique. The feature sizes obtainable using the described methods range from about 1 [mu]m to about 1 nm, and often range from about 100 nm to about 10 nm.

In one embodiment, the exposure apparatus includes a phase shift mask in the form of a UV translatable rotatable mask having a particular phase shift relief on its outer surface, another embodiment of the phase shift mask technique The penetrable rotatable mask (which is typically a cylinder) may have a polymeric film (which is a phase shift mask) and the mask is attached to the outer surface of the cylinder. When it is difficult to obtain good and uniform contact with the surface of the substrate (especially for large processing areas), it is advantageous for the polymer film to be a conformal elastic polymer film (e.g., PMDS), wherein the conformal elastic polymer film Good conformal contact with the substrate can be achieved by Van der Valli. The polymeric film phase shift mask can be constructed from a plurality of layers wherein the outer layer is patterned to more accurately represent the specified feature size in a radiation sensitive (light sensitive) layer.

Another embodiment of the exposure apparatus utilizes a soft, resilient reticle material, such as a PDMS film, having a non-penetrable feature formed on one surface thereof, wherein the surface is attached to the outer surface of the cylinder. These features may be chromium features that are fabricated on the PDMS film using one of the lithographic techniques well known in the art.

In an embodiment of an exposure apparatus comprising a surface plasmonic technique, a metal layer or film system is laminated or deposited onto the outer surface of the rotatable mask, wherein the rotatable mask is typically a wearable Through the cylinder. The metal layer or film has a specific series of nanoperforations. In another embodiment of the surface plasmonics technique, a layer of metallic nanoparticle is deposited on the outer surface of the permeable, rotatable mask to achieve surface plasmonic enhanced nanopatterning. A source of radiation is provided to the interior of the penetrable cylinder. For example and without limitation, a UV lamp can be mounted inside the cylinder. Alternatively, the radiation source may be disposed outside of the cylinder, and the light from the radiation source is directed to the interior of the cylinder via one or both ends of the cylinder. An optical system (including mirrors, lenses, or a combination thereof) can be used to direct radiation from a surface of the cylinder or inside the cylinder toward a particular area of the interior of the cylinder. A grating can be used to direct the radiation within the cylinder towards the contact area of the mask substrate. A grating can be utilized via a waveguide to direct radiation toward the mask substrate region (combined). Typically, the waveguide or grating is disposed inside the cylinder to redirect the radiation toward the contact area between the outer surface of the cylinder and the surface of the substrate to be imaged.

In a particular embodiment of an optical radiation source, an OLED flexible display can be attached to the exterior of the rotatable mask to emit light from each pixel toward the substrate. In this case, the rotatable mask does not need to be permeable. In addition, a particular pattern of radiation-sensitive material to be transferred to the substrate can be generated depending on the application by controlling the light emitted from the OLED. The pattern to be transferred can be changed "on the fly" without having to close the production line.

In order to provide high yields of pattern transfer to radiation sensitive materials and to increase the quality of the nanopatterned surface areas, it may be beneficial to move the substrate or rotatable mask (e.g., cylinder) relative to each other. When the substrate is stationary, the cylinder is rotated on the surface of the substrate; or when the cylinder is stationary, the substrate is moved toward the cylinder. It is advantageous to move the substrate towards the cylinder for the reasons discussed below.

It is important to be able to control the force, which is the line of contact between the cylinder and the radiation-sensitive material on the surface of the substrate (eg the elastic nano-patterned film on the surface of the cylinder and the photoresist on the surface of the substrate) Contact line between agents). To control this line of contact, the cylinder can be supported by a stretching device, such as a spring, which compensates for the weight of the cylinder. The substrate or cylinder (or both) are moved toward each other (up and down) so that the spacing between the surfaces can be reduced until a cylindrical surface is achieved with the radiation sensitive material (eg elastic nanopatterning) The contact between the film and the photoresist on the surface of the substrate). The elastic nanopatterned film will create a bond with the photoresist via van der Waals force. The substrate position is then moved back to the (downward) spring extended position, but the elastic nanopatterned film remains in contact with the photoresist. The substrate can then be moved toward the cylinder, forcing the cylinder to rotate, maintaining dynamic contact between the elastic nanopatterned film and the photoresist on the surface of the substrate. Alternatively, the cylinders can each be rotated and the substrate moved, but moved synchronously, which will ensure non-sliding contact during dynamic exposure.

A plurality of cylinders can be combined into a system and arranged to expose the radiation-sensitive surface of the substrate by sequential mode to provide two, three, and multiple patterning of the substrate surface. This exposure technique can be used to provide higher resolution. The relative positions of the cylinders can be controlled by an interferometer and a suitable computerized controller.

In another embodiment, the exposure dose affects the lithography, so an edge lithography (where narrow features can be formed that correspond to the displacement of the phase in the PDMS mask) can be changed to a conventional contact lithography. And the characteristic size of the developed photoresist can be controlled by the exposure dose. Such exposure dose control is possible by controlling the power of the radiation source or the rotational speed of the cylinder (exposure time). The feature size produced in the photoresist can also be controlled by, for example, changing the wavelength of the exposure radiation (light source).

The mask on the cylinder can be oriented at an angle relative to the direction of movement of the substrate. This can result in pattern formation against the substrate in different directions. Two or more cylinders may be arranged in sequence to create a 2D pattern.

In another embodiment, the penetrable cylindrical chamber need not be rigid, but can be made of a flexible material that can be pressurized with an optically permeable gas. The mask may be a cylindrical wall or may be a conformal material on the surface of the cylindrical wall. This allows the cylinder to be rolled over an uneven substrate while achieving conformal contact with the surface of the substrate.

As a prelude to the detailed description, it should be noted that the singular forms "a" and "the"

When the word "about" is used herein, it is meant to mean that the nominal value presented is within ±10%.

Embodiments of the present invention are directed to methods and apparatus for nanopatterning large area substrates in which a rotatable mask is used to image the radiation sensitive material. Typically, the rotatable mask comprises a cylinder. The nanopatterning technique utilizes near-field photolithography in which the wavelength of the radiation used to image one of the radiation-sensitive layers on the substrate is 438 nm or less, and the mask and base used to pattern the substrate therein. Material contact. Near-field photolithography can utilize a phase shift mask or a plurality of nanoparticles that can penetrate a rotating cylinder, or a surface plasmonic technique can be used in which the metal layer on the surface of the rotating cylinder contains more A nano hole. The description provided below is merely an example of the many possibilities that one skilled in the art can understand while reading the description of the present invention.

Although a rotating mask for creating a nanopattern in a layer of radiation-sensitive material can have any advantageous configuration, and several of these configurations are described below to be imaged substrates with minimal maintenance costs. Hollow cylinders are particularly advantageous in terms of manufacturability. 1A shows a cross-sectional view of an embodiment of an apparatus 100 for patterning a large area of substrate material, wherein a radiation permeable cylinder 106 has a hollow interior 104 in which a radiation source 102 is located. In this embodiment, the outer surface 111 of the cylinder 106 is patterned to have a particular surface relief 112. The cylinder 106 is rolled over a radiation sensitive material 108 that is positioned above the substrate 110. 1B shows a top view of the apparatus and substrate depicted in FIG. 1A with the radiation sensitive material 108 having been imaged 109 by radiation (not shown) passing through the surface relief 112. The cylinder rotates in the direction indicated by arrow 118, and radiation from radiation source 102 passes through a nanopattern on outer surface 103 of rotating cylinder 106 to impart a radiation sensitive layer on substrate 108 (not shown). Imaging is provided while a developed pattern 109 is provided within the radiation sensitive layer. The radiation sensitive layer is then developed to provide a nanostructure on the surface of the substrate 108. In FIG. 1B, the rotatable cylinder 106 and the substrate 120 are shown as being driven independently of each other. In another embodiment, the substrate 120 can be held in dynamic contact with the rotatable cylinder 106 and moved in a direction toward or away from the contact surface of the rotatable cylinder 106 to provide motion to a static rotatable circle. Cartridge 106. In yet another embodiment, the substrate is static while the rotatable cylinder 106 can be rotated on the substrate 120.

A particular surface relief 112 can be etched into the outer surface of the penetrable rotating cylinder 106. Alternatively, a particular surface relief 112 may be present on a film of polymeric material that is attached to the outer surface of the rotating cylinder 106. The polymeric material film can be fabricated by depositing a polymeric material onto a mold (master). The master which is built on the ruthenium substrate is typically produced, for example, by writing a pattern of electron beams to a photoresist present on the ruthenium substrate. The pattern is then etched into the tantalum substrate. The pattern on the original mold is then copied into the polymeric material deposited on the surface of the mold. Preferably, the polymeric material is a conformal material that exhibits sufficient stiffness to wear as a contact mask against the substrate, but which can also form good contact with the radiation-sensitive material on the surface of the substrate. An example of a conformal material that is commonly used as a transfer mask material is PDMS, which can be cast onto the surface of a master mold, hardened with UV radiation, and stripped from the mold to produce a good replication of the mold surface.

Figure 2 shows a cross-sectional view of another embodiment of an apparatus 200 for patterning a large area of substrate material. In FIG. 2, the substrate is a film 208 on which a pattern is imaged by radiation, wherein the radiation penetrates the first film as it travels from the roll 211 to the roll 213 ( The surface relief 212 on the cylinder 206 can be penetrated. A second cylinder 215 is provided on the back side 209 of the membrane 208 to control contact between the membrane 208 and the first cylinder 206. Radiation source 202 present in hollow space 204 within penetrable cylinder 206 can be a mercury vapor lamp or another source of radiation that provides a wavelength of radiation of 365 nm or less. The surface relief 212 can be, for example, a phase shift mask, wherein the mask includes a diffractive surface having a plurality of recesses and protrusions as discussed above in the "Prior Art" section. The convex portion is in contact with the surface of the positive photoresist (radiation-sensitive material), and the surface is exposed to electromagnetic radiation via the phase mask. The phase shift caused by the penetration of the radiation relative to the protrusions through the recess is substantially complete. The minimum value of the intensity of the electromagnetic radiation is thereby generated at the boundary between the concave portion and the convex portion. The elastomeric mask is well conformed to the surface of the photoresist, and subsequent development of the photoresist can achieve features less than 100 nm.

Figure 3 shows a cross-sectional view of another embodiment of an apparatus 300 for patterning a large area of substrate material. The substrate is a film 308 that travels from the reel 311 to the reel 313. A layer of radiation-sensitive material (not shown) is provided on the top side and bottom side 309 of film 308. There is a first penetrable cylinder 306 having a hollow center 304 including a radiation source 302 having a surface relief 312 for patterning the top side 310 of the membrane 308. There is a second penetrable cylinder 326 having a hollow center 324 including a radiation source 322 having a surface relief 332 for patterning the bottom side 309 of the membrane 308.

4A shows a cross-sectional view 400 of one embodiment of a penetrable cylinder 406 that includes a hollow central region 404 having an internal radiation source 402. Surface relief 412 is a conformal structure that includes a polymeric film 415 having a patterned surface 413 that is particularly useful in near-field lithography. The polymeric material of the patterned surface 413 must be sufficiently rigid to allow the pattern to contact the surface of the substrate to be imaged in place. On the other hand, the polymeric material must conform to the surface of the radiation-sensitive material (not shown) to be imaged.

4B shows an enlarged view of surface 413, which is a surface relief polymer structure 413 positioned on top of polymer substrate material 415. In FIG. 4B, the polymeric substrate material 415 can be the same polymeric material as the patterned surface material 413, or can be a different polymeric material. A penetrable conformal material, such as polyoxyalkylene or PDMS, can be used as the polymer film 415, which can be combined with a harder layer of penetrable cover material (eg, PDMS with different mixing ratios, or PMMA). combination. This provides a patterned surface 413 that helps to avoid distortion of the features when in contact with a location on the radiation-sensitive surface of the substrate (not shown), while the polymeric substrate material simultaneously provides surface contact with the substrate. Roughly conformal.

5A shows a cross-sectional view 500 of a penetrable cylinder 506 having a hollow central region 504 that includes a radiation source 502, wherein surface 511 presents an alternate embodiment of surface relief 512. 5B shows an enlarged view of surface relief 512, which is a thin metal layer 514 patterned into a series of nanoholes 513, wherein the metal layer is present on the outer surface 511 of the hollow penetrable cylinder 506. on. The metal layer can be a patterned layer that is attached to the outer surface of the penetrable cylinder 506. Alternatively, the metal layer can be deposited on the surface of the penetrable cylinder by evaporation or sputtering or other techniques known in the art, and then etched or detached using a laser to provide a patterned metal. Surface 511. Figure 5C shows an alternative surface relief 522 formed from metal particles 526 that are coated on the outer surface 511 of the hollow penetrable cylinder 506 or coated on the surface. Attached to a permeable membrane 524 on the outer surface 511 of the hollow penetrable cylinder 506.

6A is a three-dimensional representation 600 of a penetrable cylinder 604 having a patterned surface 608. A source of radiation (not shown) is present inside the penetrable cylinder 604. The penetrable cylinder 604 is suspended above the substrate 610 by a stretching device 602, which is shown as a spring in the schematic 600. Those skilled in the art of mechanical engineering will be aware of a number of stretching devices that can be used to achieve a suitable amount of contact between the outer surface 608 of the pierceable cylinder 604 and the surface of the substrate 610. In an embodiment method using the apparatus shown in Figure 6A, the apparatus is used to image a radiation-sensitive material (not shown) on a substrate 610, wherein the substrate 610 is a polymer film, a polymer The film can be supplied to and taken from the roll-to-roll system of the type of Figure 2. The penetrable cylinder 604 is lowered toward the polymeric film substrate (or the polymeric film substrate is raised) until it comes into contact with the radiation sensitive material. A polymeric film, typically an elastomer, will establish a van der Waals bond with the radiation sensitive material. The penetrable cylinder 604 can then be raised (or the polymeric film substrate lowered) to a position where the surface 608 of the penetrable cylinder 604 maintains contact with the surface of the radiation-sensitive material. However, the tension between the two surfaces is such that the force exerted on the surface 608 is minimal. This allows the use of very fine nanopatterning features on the surface 608 of the penetrable cylinder 604. As the substrate 610 begins to move, the penetrable cylinder 604 will also move, forcing the penetrable cylinder 604 to rotate, maintaining dynamic contact between the radiation sensitive material and the underlying polymeric film substrate 610. At any time during dynamic contact, the contact between the cylinder and the photoresist layer is limited to a narrow line. Due to the strong Valer force between the elastic film on the outer surface of the cylinder and the radiation-sensitive (light-sensitive) layer on the substrate, the contact can be throughout the process and along the entire surface of the cylinder (length) The width is maintained evenly. In the case where Van der Waals forces are unable to provide a sufficiently strong adhesion between the cylinder contact surface and the light sensitive layer, an actuating (rotating) cylinder can be used, wherein the actuating (rotating) cylinder is used with the substrate The displacement moves the synchronized stepper motor. This provides a non-slip exposure process for polymers or other cylindrical surface materials that do not provide a strong adhesion to the substrate.

6B is a schematic diagram of an embodiment 620 in which radiation for achieving imaging is provided from a radiation source 612 external to the cylinder 604, the radiation being internally dispersed 615 and 616 within the hollow portion of the cylinder 604. Various lenses, mirrors, and combinations thereof can be used to direct radiation through the patterned mask surface 608 through the penetrable cylinder 604 toward a radiation-sensitive surface (not shown) of the substrate 608.

6C is a schematic illustration of an embodiment 630 in which radiation for achieving visualization of the radiation-sensitive material is provided from a location outside the penetrable cylinder 604. External radiation source 612 is focused 617 into a waveguide 618 and is dispersed from waveguide 618 to a grating 620, which is positioned on inner surface 601 of cylinder 604.

Figure 6D is a schematic illustration of an embodiment 640 in which radiation for achieving imaging is provided from two external sources 612A and 612B and each focused 621 and 619 to a grating 620, wherein the grating 620 is in the cylinder On the inner surface 601 of 604.

FIG. 7A is a schematic diagram 700 showing the use of a plurality of cylinders, such as two cylinders 702 and 704 in series to provide multiple patterning, wherein the multiple patterning can, for example, achieve higher resolution. Information from an interferometer (not shown) and a computerized control system (not shown) can be used to control the relative positions of, for example, cylinders 702 and 704.

FIG. 7B is a schematic diagram 720 showing a pattern 706 developed and developed by the radiation sensitive material 710 by the first cylinder 702. The change pattern 708 is a pattern in which the radiation-sensitive material 710 is developed and developed when the pattern 708 is changed by using a combination of the first cylinder 702 and the second cylinder 704.

Figure 8 shows a cross-sectional view of a deformable cylinder 800 in which the interior 804 of the deformable cylinder 800 is pressurized using apparatus 813, wherein the apparatus 813 provides an optically permeable gas (e.g., nitrogen). The outer surface 811 of the deformable cylinder 800 can be a conformal material nanopatterned/nanostructured film 812 that is rolled onto a non-planar surface 805 so that radiation from the radiation source 802 can be accurately applied Above the surface 816 of the substrate 805.

In another embodiment, a liquid having a refractive index greater than one can be used between the surface of the cylinder and a radiation sensitive (e.g., light sensitive) material on the surface of the substrate. For example, water can be used. This can increase the contrast of the pattern features in the light sensitive layer.

While the invention has been described in detail with reference to the various embodiments of the invention Therefore, the scope of the invention should be determined by the scope of the appended claims.

100. . . device

102. . . Radiation source

103. . . The outer surface

104. . . Hollow interior

106. . . Radiation permeable cylinder

108. . . Radiation sensitive material

109. . . Imaging

110. . . Substrate

111. . . The outer surface

112. . . Surface relief

118. . . arrow

200. . . device

202. . . Radiation source

204. . . Hollow space

206. . . First (penetrable) cylinder

208. . . membrane

209. . . Dorsal side

211. . . reel

212. . . Surface relief

213. . . reel

215. . . Second cylinder

300. . . device

302. . . Radiation source

304. . . Hollow center

306. . . First penetrable cylinder

308. . . membrane

309. . . Bottom side

310. . . Top side

311. . . reel

312. . . Surface relief

313. . . reel

322. . . Radiation source

324. . . Hollow center

326. . . Second penetrable cylinder

332. . . Surface relief

400. . . Sectional view

402. . . Internal radiation source

404. . . Hollow center

406. . . Penetrating cylinder

412. . . Surface relief

413. . . Patterned surface

415. . . Polymer film

500. . . Sectional view

502. . . Radiation source

504. . . Hollow center

506. . . Penetrating cylinder

511. . . surface

512. . . Surface relief

513. . . Nano hole

514. . . Metal layer

522. . . Surface relief

524. . . Penetrating film

526. . . Metal particles

600. . . Three-dimensional schematic

601. . . The inner surface

602. . . Stretching device

604. . . Penetrating cylinder

608. . . Patterned surface

610. . . Substrate

612. . . Radiation source

612A. . . External radiation source

612B. . . External radiation source

615. . . spread

616. . . spread

617. . . Focus

618. . . waveguide

619. . . Focus

620. . . Grating

621. . . Focus

630. . . Example

640. . . Example

700. . . schematic diagram

702. . . Cylinder

704. . . Cylinder

706. . . pattern

708. . . Change pattern

710. . . Radiation sensitive material

720. . . schematic diagram

800. . . Deformable cylinder

802. . . Radiation source

804. . . internal

805. . . Non-flat surface

811. . . The outer surface

812. . . membrane

813. . . device

816. . . surface

The exemplary embodiments of the present invention can be understood and understood by reference to the foregoing description. It is understood that the drawings are only for the purpose of understanding the exemplary embodiments of the invention,

1A shows a cross-sectional view of an embodiment of an apparatus 100 for patterning a large area of substrate material, wherein a radiation permeable cylinder 106 has a hollow interior 104 in which a radiation source 102 is located. In this embodiment, the outer surface 111 of the cylinder 106 is patterned to have a particular surface relief 112. The cylinder 106 is rolled over a radiation sensitive material 108 that is positioned above the substrate 110.

1B shows a top view of the apparatus and substrate depicted in FIG. 1A with the radiation sensitive material 108 having been imaged 109 by radiation (not shown) passing through the surface relief 112.

Figure 2 shows a cross-sectional view of another embodiment of an apparatus 200 for patterning a large area of substrate material. In FIG. 2, the substrate is a film 208 on which a pattern is imaged by radiation, wherein the radiation penetrates the first film as it travels from the roll 211 to the roll 213 ( The surface relief 212 on the cylinder 206 can be penetrated. A second cylinder 215 is provided on the back side 209 of the membrane 208 to control contact between the membrane 208 and the first cylinder 206.

Figure 3 shows a cross-sectional view of another embodiment of an apparatus 300 for patterning a large area of substrate material. In FIG. 3, the substrate is a film 308 that travels from the reel 311 to the reel 313. A first penetrable cylinder 306 having a surface relief 312 is used to pattern the top side 310 of the membrane 308, and a second penetrable cylinder 326 having a surface relief 332 is used to pattern the membrane 308. The bottom side 309.

4A shows a cross-sectional view 400 of one embodiment of a penetrable cylinder 406 that includes a hollow central region 404 having an internal radiation source 402. The surface relief region 412 is a conformal structure that includes a polymer film 415 having a patterned surface 413 that is particularly useful in near field lithography.

4B shows an enlarged view of surface 413, which is a surface relief polymer structure 413 positioned on top of polymer substrate material 415. In FIG. 4B, the polymeric substrate material 415 can be the same polymeric material as the patterned surface material 413, or can be a different polymeric material.

5A shows a cross-sectional view of an alternate embodiment of surface relief 512, wherein the surface relief 512 is positioned on a hollow penetrable cylinder 506.

5B shows an enlarged view of surface relief 512, which is a thin metal layer 514 patterned into a series of nanoholes 513, wherein the metal layer is attached to the hollow penetrable cylinder 506. On the surface 511.

Figure 5C shows an alternative surface relief 522 for use on the surface of the penetrable cylinder 506. The surface relief 522 is formed from metal particles 526 that are directly coated on the outer surface 511 of the hollow penetrable cylinder 506 or coated on the hollow penetrable circle. A permeable membrane 524 is formed on the outer surface 511 of the barrel 506.

6A is a three-dimensional schematic 600 of a penetrable cylinder 604 having a patterned surface 608 that is suspended above the substrate 610 by a stretching device 602, wherein Stretching device 602 is shown as a spring in schematic 600.

6B is a schematic diagram of an embodiment 620 in which radiation for achieving imaging is provided from a radiation source 612 external to the cylinder 604, the radiation being internally dispersed 615 and 616 within the hollow portion of the cylinder 604.

6C is a schematic diagram of an embodiment 630 in which radiation for achieving imaging is provided from an external source of radiation 612. External radiation source 612 is focused 617 into a waveguide 618 and is dispersed from waveguide 618 to a grating 620, which is positioned on inner surface 601 of cylinder 604.

Figure 6D is a schematic illustration of an embodiment 640 in which radiation for achieving imaging is provided from two external sources 612A and 612B and each focused 621 and 619 to a grating 620, wherein the grating 620 is in the cylinder On the inner surface 601 of 604.

FIG. 7A is a schematic diagram 700 showing the use of a plurality of cylinders, such as two cylinders 702 and 704 in series to provide multiple patterning, wherein the multiple patterning can, for example, achieve higher resolution.

FIG. 7B is a schematic diagram showing a pattern 706 that is developed by the first cylinder 702 to be developed and developed by the radiation-sensitive material 710. The change pattern 708 is a pattern in which the radiation-sensitive material 710 is developed and developed when the pattern 708 is changed by using a combination of the first cylinder 702 and the second cylinder 704.

Figure 8 shows a cross-sectional view of a deformable cylinder 800 in which the interior 804 of the deformable cylinder 800 is pressurized using apparatus 813, wherein the apparatus 813 provides an optically permeable gas. The outer surface 811 of the deformable cylinder 800 can be a conformal material nanopatterned/nanostructured film 812 that is rolled onto a non-planar surface 805 so that radiation from the radiation source 802 can be accurately applied Above the surface 816 of the substrate 805.

600. . . Three-dimensional schematic

602. . . Stretching device

604. . . Penetrating cylinder

608. . . Patterned surface

610. . . Substrate

Claims (31)

A method of near-field nano-lithography, comprising: a) providing a substrate having a radiation-sensitive layer on a surface of the substrate; b) providing a rotatable mask, wherein the rotatable mask is a surface of the rotatable mask having a nano-pattern; c) contacting the nano-pattern with the radiation-sensitive layer on the surface of the substrate; d) rotating the rotatable mask over the radiation-sensitive layer, Radiation is spread through the nanopattern whereby an image is created in the radiation sensitive layer, wherein the image has a feature size ranging from less than 1 [mu]m to about 1 nm. The method of claim 1, wherein the feature size is in the range of from about 100 nm to about 10 nm. The method of claim 1, wherein the radiation has a wavelength of 436 nm or less. The method of claim 1, wherein the nanopattern is a conformal nanopattern conforming to the radiation sensitive layer on the surface of the substrate. The method of claim 4, wherein the conformal nanopattern is a shaped or nanostructured polymeric material. The method of claim 3, wherein the rotatable mask is a phase shift mask that causes radiation to form an interference pattern in the radiation sensitive layer. The method of claim 3, wherein the mask utilizes surface plasmonic behavior. The method of claim 1, wherein the rotatable mask is a cylinder. The method of claim 8, wherein the cylinder has a flexible wall whereby the cylindrical shape can be deformed upon contact with the surface of the substrate. The method of claim 9, wherein an optically permeable gas is used to fill the cylinder. The method of claim 3, wherein the rotatable mask is a penetrable cylinder whereby radiation can be transmitted from a location within the cylinder. The method of claim 11, wherein the mask is a phase shift mask that exhibits an embossment on the surface of the penetrable cylinder. The method of claim 11, wherein the mask is a phase shift mask present on a layer coated over the surface of the cylinder. The method of claim 13, wherein the phase shift mask is composed of a plurality of layers, and the outer layer is patterned by nanometer to more accurately represent the specified feature size in the light sensitive layer. The method of claim 8, wherein the substrate is held in dynamic contact with the rotatable cylinder and is rotatable toward or away from the rotatable cylinder during radiation from the contact surface of the rotatable cylinder. The contact surface of the cylinder is moved. The method of claim 8, wherein the cylinder is rotated on the substrate while the substrate is stationary. The method of any of claims 1-16, wherein the plurality of rotating masks are in contact with a radiation sensitive layer. The method of claim 1, wherein a step is used a motor and a motorized substrate displacement mechanism to independently move the rotatable mask to the surface of the substrate, and wherein the movement of the rotatable mask and the surface of the substrate is synchronized with each other, thereby achieving the radiation sensitive layer One does not slide the contact exposure. The method of claim 1 or claim 18, wherein a liquid is supplied to the interface between the rotatable mask and the surface of the substrate. An apparatus for performing near-field lithography, comprising: a) a rotatable mask having a nano pattern on an outer surface of the mask; and b) a radiation source, wherein the nano pattern is When the radiation sensitive material layer is in contact, the radiation source provides radiation having a wavelength of 436 nm or less from the nanopattern. The apparatus of claim 20, wherein the rotatable mask is permeable. The apparatus of claim 21, wherein the rotatable mask is a phase shift mask. The apparatus of claim 21, wherein the rotatable mask utilizes radiation generated by surface plasmonic techniques. The apparatus of claim 22, wherein the surface of the mask comprises a metal layer comprising a plurality of nanoholes. The apparatus of any one of claims 20-24, wherein the rotatable mask is a cylinder. The apparatus of claim 25, wherein the cylinder is a flexible cylinder. The apparatus of claim 26, wherein the flexible cylinder is filled with an optically permeable gas. The apparatus of claim 25, wherein the plurality of cylinders exhibit a configuration such that the cylinders sequentially pass through a substrate. The apparatus of claim 25, wherein a plurality of cylinders are present, and wherein one of the cylinders is present on a top side and a bottom side of a substrate to be imaged by the apparatus. The apparatus of claim 29, wherein at least one cylinder that delivers imaging radiation is present on a top side and a bottom side of a substrate that is imaged by the apparatus. The apparatus of claim 20, wherein a rotatable mask is suspended above the substrate by a stretching device, the stretching device being adjustable to control being applied to the rotatable mask The strength of the surface that touches.