CN115786872A - Surface selective atomic layer deposition method using pre-bonding method - Google Patents

Abstract

The invention belongs to the field of optical and semiconductor manufacturing, relates to the field of optical coating, and particularly relates to a surface selective atomic layer deposition method using a pre-bonding method. Providing a functional glass element and a bonding auxiliary element, performing surface polishing treatment on a surface to be protected of the functional glass element and a protective surface of the bonding auxiliary element, then attaching the surface to be protected and the protective surface, performing pre-bonding treatment until no bubbles are generated at the edge of the attaching surface of the surface to be protected and the protective surface, then performing atomic layer deposition, and performing debonding after the atomic layer deposition; wherein the pre-bonding treatment adopts a direct bonding method, and the pressure of the direct bonding method is 0.05-0.1 MPa. The method provided by the invention can avoid the atomic layer deposition and the pollution of devices, and has the advantages of low damage risk, simple and easy operation, low cost and good effect.

Description

A method for surface-selective atomic layer deposition using a pre-bonding method

technical field

The invention belongs to the field of optics and semiconductor manufacturing, relates to the field of optical coating, in particular to a surface selective atomic layer deposition method using a pre-bonding method.

Background technique

The information disclosed in this background section is only intended to increase the understanding of the general background of the present invention, and is not necessarily taken as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to those skilled in the art.

In the manufacturing process of optical devices and semiconductor devices, in order to realize the miniaturization, multi-function and high performance of the devices, it is often necessary to deposit films with special properties on the electrical or optical surface patterning, such as high refractive index, high The characteristic film layers such as compactness and high dielectric constant can provide certain functions while encapsulating and protecting the pattern. Atomic layer deposition technology has special advantages in the preparation of these films. Its high shape retention, high density, and precise controllable thickness make it the best choice for surface pattern coating. But at the same time, atomic layer deposition technology, as a coating technology for adsorption film growth, will grow film layers on all exposed surfaces of optical components or optoelectronic devices. In the conventional sense, atomic layer deposition is deposited on all surfaces non-selective technology. That is to say, a thin film will also be deposited on the place where the film layer is not needed, that is, the non-deposited surface, and because the film layer has good adhesion, it is difficult to remove later.

According to the research of the inventors, most of the existing selective atomic layer deposition technologies block or inhibit the growth of the film layer in the area by coating or adhering protective materials, surface modification and other methods on the surface to be protected. On the one hand, this method of inhibiting the growth of the film layer can only reduce the deposition rate of the film layer, and cannot completely avoid the deposition of the film layer; on the other hand, the surface coating material often needs to be removed by subsequent processes, which increases the Risk of contamination, damage, reduced process efficiency.

Contents of the invention

In order to solve the deficiencies of the prior art, the object of the present invention is to provide a surface-selective atomic layer deposition method using a pre-bonding method, which can avoid atomic layer deposition and device contamination, has low risk of damage, and is simple and easy to operate , low cost and good effect.

In order to achieve the above object, the technical solution of the present invention is:

On the one hand, a surface selective atomic layer deposition method using a pre-bonding method provides a functional glass component and a bonding auxiliary component, and performs surface polishing on the surface to be protected of the functional glass component and the protective surface of the bonding auxiliary component, Then attach the surface to be protected and the protection surface, and then carry out pre-bonding treatment until no bubbles are generated at the edge of the bonding surface between the surface to be protected and the protection surface, and then carry out atomic layer deposition, and debond after atomic layer deposition; wherein, the pre-bonded The bonding treatment adopts a direct bonding method, and the pressure applied during the direct bonding method is 0.05-0.1 MPa.

The invention adopts the pre-bonding method, which can effectively protect the surface that does not need to deposit the film layer during the atomic layer deposition process, and re-expose the non-deposition surface by debonding after the film layer deposition is completed.

Available pre-bonding methods include direct bonding, eutectic bonding and anodic bonding.

The direct bonding method applies a certain pressure and temperature to the substrate to be bonded, so that the bonding surface is bonded and a certain bonding strength is generated. The factors are very sensitive, and direct bonding needs to be carried out under relatively high purification conditions, and the applied pressure and temperature are often high, which is easy to cause damage to the substrate.

The eutectic bonding method needs to introduce a medium such as an adhesive film or solder to the bonded substrate, which can achieve higher air density and better air density stability. However, in the chip/wafer stacking technology and the manufacture of optical devices, the introduction of Bonding media can cause poor device performance.

The anodic bonding method connects the substrate to be bonded to the electrode. Under the action of the electric field, the sodium ions in the glass will drift towards the negative electrode, forming a depletion layer on the glass surface next to the silicon wafer or quartz, and the depletion layer has a negative charge. , The silicon wafer or quartz is positively charged, and there is a large electrostatic attraction between the silicon wafer or quartz and the glass, so that the two are in close contact and bonded. However, anodic bonding has restrictions on the material of the bonding substrate, which needs to include a glass substrate, and the glass needs to contain alkali metal ions that can drift under the action of an electric field, mainly sodium ions; at the same time, in the bonding process of optical components Among them, if the thickness of the optical substrate is large, it is often necessary to apply a very high voltage to achieve the required electric field strength, and the requirements for the power supply equipment are relatively high.

The present invention adopts the direct bonding method to carry out the pre-bonding treatment, and it only needs to protect the surface to be protected of the functional glass element by using the bonding overlapping surface, without completely bonding the two elements together, that is, the bonding strength is required to be low, so The requirements for surface flatness, roughness, scratches, attached particles, pressure, temperature and other factors of the substrate are not high. However, studies have shown that air bubbles exist at the edge of the bonded surface after pre-bonding treatment, which is not conducive to the protection of the surface to be protected during the atomic layer deposition process. The pre-bonding treatment of the present invention does not generate bubbles at the edge of the bonded surface between the surface to be protected and the protected surface, and can effectively prevent the entry of precursor gas, thereby protecting the non-deposited surface for growing film layers. At the same time, when performing atomic layer deposition, the heating process before deposition will generate a certain degree of strength on the bonding surface, which can further improve the degree of bonding between the surface to be protected and the protection surface, and further effectively prevent the entry of precursor gas. In addition, using the direct bonding method for pre-bonding treatment is more conducive to debonding due to lower requirements for bonding strength, thereby avoiding device damage caused by excessive bonding strength.

Functional glass components, the substrate is generally double-sided polished and parallel flat glass sheets or cylinders, one of the surfaces is deposited with a silicon dioxide film layer by chemical vapor phase, and then processed by photolithography, dry etching, cleaning and other processes to produce graphics The functional layer is then deposited on the surface by atomic layer deposition technology with a certain thickness of film layer different from the refractive index of the substrate. The film layer encapsulates the graphic structure and prevents the structure from being polluted or damaged; The spectral transmittance of the surface. In the process of atomic layer deposition, since the growth method of the film layer is adsorption growth, the film layer will be deposited on the surface exposed to the deposition chamber, so not only the required film layer is deposited on the graphic surface of the functional element, but also on the The side surface and the back of the element are also deposited with the same thickness of the film layer. The back of the functional element often needs to be coupled with other optical devices, and does not need to deposit a film layer, but it needs to be protected during the deposition process. Thus, on the other hand, an application of the above-mentioned surface-selective atomic layer deposition method using a pre-bonding method in backside protection of functional glass components.

The beneficial effects of the present invention are:

Before atomic layer deposition, the present invention uses bonding auxiliary components to directly bond the surface of the functional glass element to be protected until no bubbles are generated at the edge of the bonding surface. At the same time, the heating process before atomic layer deposition will make the bonding surface A certain degree of strength can be generated to further improve the bonding degree of the two surfaces, thereby effectively preventing the entry of the precursor gas, thereby protecting the non-deposition surface to grow the film layer. After the deposition is finished and the temperature is lowered, the two bonded surfaces are debonded by applying a load to re-expose the non-deposited surface. In this way, the required film layer is deposited on the surface of the functional glass element, and the non-deposited surface can be effectively protected.

The selective atomic layer deposition method provided by the present invention does not have high requirements on the cleanliness of the target surface during bonding, even if bubbles are generated during bonding, it will not affect the hindrance to the entry of the precursor, and only need to prevent the bubbles from forming on the bonding surface Edges are created. At the same time, due to the low requirements on surface flatness, roughness, scratches, attached particles and other factors, the generated air bubbles will reduce the bonding strength of the entire surface, which is beneficial to the debonding process at the end of deposition.

Description of drawings

The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention, and the schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations to the present invention.

Fig. 1 is a schematic structural view of the bubbles that do not meet the requirements generated during the back protection of the functional glass element in Example 1 of the present invention;

Fig. 2 is a structural schematic diagram of unqualified air bubbles generated when the back side of the functional glass element in Example 1 of the present invention is protected;

Fig. 3 is a schematic diagram of the structure of bubbles that meet the requirements generated during the back protection of the functional glass element in Example 1 of the present invention;

Among them, 1. Functional glass components, 2. Bonding auxiliary components, 3. Bubbles.

Detailed ways

It should be noted that the following detailed description is exemplary and intended to provide further explanation of the present invention. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

It should be noted that the terminology used here is only for describing specific embodiments, and is not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly dictates otherwise, the singular is intended to include the plural, and it should also be understood that when the terms "comprising" and/or "comprising" are used in this specification, they mean There are features, steps, operations, means, components and/or combinations thereof.

In view of the problems of low deposition rate, unavoidable film deposition, device pollution, and device damage in the existing selective atomic layer deposition technology, the present invention proposes a surface selective atomic layer deposition method using a pre-bonding method.

A typical embodiment of the present invention provides a surface selective atomic layer deposition method using a pre-bonding method, providing a functional glass component and a bonding auxiliary component, and the surface to be protected of the functional glass component and the bonding auxiliary component Polish the surface of the protected surface, then bond the surface to be protected with the protected surface, and then carry out pre-bonding treatment until no bubbles are generated at the edge of the bonding surface between the surface to be protected and the protected surface, and then perform atomic layer deposition. Debonding is carried out after the deposition; wherein, the pre-bonding treatment adopts a direct bonding method, and a pressure of 0.05-0.1 MPa is applied during the direct bonding method.

In some embodiments, the surface to be protected and the protected surface are wiped with water before atomic layer deposition. Wiping with water can make the surface to be protected and the protection surface wet, which is convenient for lamination. At the same time, some air bubbles will be formed during pre-bonding, which will reduce the final bonding strength and reduce the difficulty of understanding the bonding.

The higher the ALD temperature, the higher the bonding strength. In order to avoid the higher bonding strength and increase the difficulty of debonding, in some embodiments, the ALD temperature is 150-250°C.

In some embodiments, plasma assist is performed during atomic layer deposition. The deposition rate can be increased by plasma assist, which can effectively control the growth of bond strength.

In some embodiments, the functional glass element is a sheet structure, and the bonding auxiliary element is a columnar structure.

In some embodiments, the upper surface of the functional glass element is deposited with a silicon dioxide film layer by chemical vapor phase, and then photolithography, dry etching, and cleaning are used to form a patterned functional layer, and then the lower surface of the functional glass element is used as the surface to be protected. noodle.

In some embodiments, before debonding, the bonding strength between the surface to be protected and the protected surface is less than 3 MPa. It can be debonded by pulling or shear loading without damaging the surface.

In some embodiments, when debonding, a tensile load is used to debond and detach the edges first, and then completely debond and detach the entire surface. In this method, a part of the bonding area is first desorbed to reduce the bonding surface, reduce the overall bonding strength, facilitate debonding, and avoid damage to the sheet-shaped functional glass element. At this time, the temperature can be carried out at room temperature. The room temperature in the present invention refers to the indoor ambient temperature, which is generally 15-30°C.

In some embodiments, the temperature for debonding is 50-150°C. An increase in temperature favors the dissociation of the bonded surfaces.

Another embodiment of the present invention provides an application of the above-mentioned surface selective atomic layer deposition method using a pre-bonding method in back protection of functional glass components.

In order to enable those skilled in the art to understand the technical solution of the present invention more clearly, the technical solution of the present invention will be described in detail below in conjunction with specific embodiments.

Example 1

A titanium oxide film layer is deposited on the patterned surface of the functional glass element, with a thickness of 500nm pre-deposited. The surface of the titanium oxide film to be deposited is the upper surface, and the pattern is a periodic slit structure with a period of 700nm, a ridge width of 300nm, a slit width of 400nm, and a depth of 400nm. The base material is a K9 optical glass sheet with a diameter of 30mm and a thickness of 0.4mm. The lower surface is a non-deposited surface, which is polished to protect the surface to be bonded. The bonding auxiliary component is a cylindrical K9 glass with a diameter of 26mm and a height of 8mm, and the surface to be bonded is polished.

At room temperature, a pressure load of 0.07 MPa is applied to directly bond the surface to be bonded of the bonding auxiliary component 2 to the non-deposition surface of the functional glass component 1, and the bubbles 3 generated by the bonding are on the edge of the bonding auxiliary component. , as shown in Figures 1-2, apply a tensile load of 0.02MPa to unbond and then re-bond until the bubbles 3 generated by the bonding are not generated at the edge; if the bubbles 3 are generated during bonding, the bubbles 3 are not in the bond The edge of the auxiliary component, as shown in FIG. 3 , can directly carry out the next step of deposition work.

Put the pre-bonded components into the chamber of the atomic layer deposition equipment, deposit a titanium oxide film at 200°C, and take it out after the deposition is completed and cooled to room temperature. The two components were fixed with tooling on the tensile loader, and when the tensile load was applied to 1.5MPa, the bonding surfaces of the two components were disengaged again, and the bonding process was completed.

The surface after debonding is not damaged, and the element distribution on the non-deposited surface is detected by XPS, and there is no infiltration of titanium elements, that is, this method protects the non-deposited surface well during the atomic layer deposition process, so that it is not polluted by the deposited film layer, and no Subsequent processing removes.

Example 2

A titanium oxide film layer is deposited on the patterned surface of the functional glass element, with a thickness of 500nm pre-deposited. The surface of the titanium oxide film to be deposited is the upper surface, and the pattern is a periodic slit structure with a period of 700nm, a ridge width of 300nm, a slit width of 400nm, and a depth of 400nm. The base material is a K9 optical glass sheet with a diameter of 30mm and a thickness of 0.4mm. The lower surface is a non-deposited surface, which is polished to protect the surface to be bonded. The bonding auxiliary component is a cylindrical K9 glass with a diameter of 26mm and a height of 8mm, and the surface to be bonded is polished. Both the protective surface of the functional glass component to be bonded and the surface to be bonded of the bonding auxiliary component are wiped with a damp dust-free cloth to make the surface to be bonded fully wet.

At room temperature, directly bond the surface to be bonded of the bonding auxiliary component to the non-deposited surface of the functional glass component (applying a pressure load of 0.05MPa), until the bubbles generated by the bonding do not occur at the edge, then it can be carried out directly The next step of deposition work.

Put the pre-bonded components into the chamber of the atomic layer deposition equipment, deposit a titanium oxide film at 200°C, and take it out after the deposition is completed and cooled to room temperature. The two components were fixed with tooling on the tensile loader, and when the tensile load was applied to 1.1MPa, the bonding surfaces of the two components were disengaged again, and the bonding process was completed.

The surface after debonding is not damaged, and the element distribution on the non-deposited surface is detected by XPS, and there is no infiltration of titanium elements, that is, this method protects the non-deposited surface well during the atomic layer deposition process, so that it is not polluted by the deposited film layer, and no Subsequent processing removes. The comparison between this example and Example 1 shows that after the surface to be bonded is wetted, not only is it easier to bond, but also it is easier to generate air bubbles and reduce the bonding strength.

Example 3

A titanium oxide film layer is deposited on the patterned surface of the functional glass element, with a thickness of 500nm pre-deposited. The surface of the titanium oxide film to be deposited is the upper surface, and the pattern is a periodic slit structure with a period of 700nm, a ridge width of 300nm, a slit width of 400nm, and a depth of 400nm. The base material is a K9 optical glass sheet with a diameter of 30mm and a thickness of 0.4mm. The lower surface is a non-deposited surface, which is polished to protect the surface to be bonded. The bonding auxiliary component is a cylindrical K9 glass with a diameter of 26mm and a height of 8mm, and the surface to be bonded is polished.

At room temperature, directly bond the surface to be bonded of the bonding auxiliary component to the non-deposited surface of the functional glass component (applying a pressure load of 0.1 MPa) until the bubbles generated by the bonding do not occur at the edge, then it can be carried out directly The next step of deposition work.

Put the pre-bonded components into the chamber of the atomic layer deposition equipment, deposit a titanium oxide film at 250°C, and take it out after the deposition is completed and cooled to room temperature. Use tooling to fix the two components on the tensile loader, use a tensile load of 1.2MPa to debond and detach the edges first, and then use a tensile load of 1.0MPa to completely debond and detach the entire surface to complete the debonding process.

The surface after debonding is not damaged, and the element distribution on the non-deposited surface is detected by XPS, and there is no infiltration of titanium elements, that is, this method protects the non-deposited surface well during the atomic layer deposition process, so that it is not polluted by the deposited film layer, and no Subsequent processing removes. The comparison between this embodiment and Example 1 shows that when the bonding strength is high, a part of the bonding area can be desorbed first to reduce the bonding surface and reduce the overall bonding strength, which is conducive to debonding and avoids damage to the flake functional glass element. damage.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (10)

1. A surface-selective atomic layer deposition method using a pre-bonding method is characterized in that a functional glass element and a bonding auxiliary element are provided, and the surface to be protected of the functional glass element and the protective surface of the bonding auxiliary element are surfaced Polishing treatment, then bonding the surface to be protected and the protection surface, and then performing pre-bonding treatment until no bubbles are generated at the edge of the bonding surface between the surface to be protected and the protection surface, then performing atomic layer deposition, and debonding after atomic layer deposition; Wherein, the pre-bonding treatment adopts a direct bonding method, and a pressure of 0.05-0.1 MPa is applied during the direct bonding method. 2. The surface-selective atomic layer deposition method using a pre-bonding method as claimed in claim 1, characterized in that, before the atomic layer deposition, the surface to be protected and the protection surface are wiped with water. 3. The surface-selective atomic layer deposition method using a pre-bonding method according to claim 1, characterized in that the temperature of the atomic layer deposition is 150-250°C. 4. The surface-selective atomic layer deposition method using a pre-bonding method as claimed in claim 1, wherein plasma assistance is performed during the atomic layer deposition. 5. The surface-selective atomic layer deposition method using a pre-bonding method according to claim 1, wherein the functional glass element is a sheet structure, and the bonding auxiliary element is a columnar structure. 6. the surface-selective atomic layer deposition method of using pre-bonding method as claimed in claim 1, it is characterized in that, the upper surface of functional glass element is by chemical vapor deposition silicon dioxide film layer, then through photoetching, dry method Etching and cleaning produce a graphic functional layer, and then use the lower surface of the functional glass element as the surface to be protected. 7. The surface-selective atomic layer deposition method using a pre-bonding method as claimed in claim 1, characterized in that, before debonding, the bonding strength between the surface to be protected and the protection surface is less than 3 MPa. 8. The surface-selective atomic layer deposition method using a pre-bonding method as claimed in claim 1, characterized in that when debonding, the edge is debonded and desorbed first by using a tensile load, and then the entire surface is completely debonded and desorbed. 9. The surface-selective atomic layer deposition method using a pre-bonding method according to claim 1, wherein the temperature is 50-150° C. when debonding. 10. Application of the surface selective atomic layer deposition method using the pre-bonding method according to any one of claims 1 to 9 in the back protection of functional glass components.

Images