A method for preparing anti-counterfeiting micro-nanostructure patterns based on nanoimprint technology

Abstract

The present invention provides a method for preparing an anti-counterfeiting micro-nano structure pattern based on nanoimprint technology. The present invention adopts polydimethylsiloxane as an imprint soft template and a two-layer glue system of ultraviolet photoresist / LOR glue to prepare a nanostructure pattern with a microscopic morphology and controllable size through nanoimprint lithography. The method is simple, easy to operate, low in cost, and high in efficiency, and a large-area nanostructure pattern can be prepared. In addition to being used to generate intelligent anti-counterfeiting micro-nano structure colors, the nanostructure pattern prepared by the present invention also has broad application prospects in the preparation of optoelectronic devices and bionic structures.

Description

Technical Field

[0001] The invention belongs to the technical field of micro-nano processing and relates to a method for preparing a micro-nano structure pattern based on nano-imprint technology. Background Art

[0002] It has been proven in theory and practice that changing the morphology and size of the micro-nanostructure on the surface of a material can be used to control the movement of photons and produce different structural colors. This structural color has special spectral characteristics that cannot be obtained through pigments. Using it for product packaging will produce novel effects and has special anti-counterfeiting capabilities. It is considered to be one of the optical anti-counterfeiting technologies with the highest security level.

[0003] In the prior art, the preparation methods for preparing nanostructures with controllable sizes on the surface of materials include two categories of "bottom-up" technology and "top-down" technology. The former mainly includes physical and chemical vapor deposition, solution coating method, etc.; the latter includes photolithography and etching technology, etc. The current level of preparation technology is relatively mature for nanostructures with a scale of more than 100nm; while for structures with a size less than 100nm, the preparation accuracy is poor. Among them, the structures less than 100nm prepared by electron beam lithography, focused ion beam lithography and other technologies have high size control accuracy, but these technologies have low output and high cost, and the resolution limit of electron beam lithography is restricted due to the scattering of the electron beam, and the problem of residual pollution of reaction gas generated by focused particle beam lithography cannot be ignored. The above problems seriously restrict the development of mass production. Summary of the invention

[0004] The technical problem solved by the present invention is that the existing anti-counterfeiting micro-nanostructure preparation method has the problems of low nanostructure size control accuracy, complex procedures, complex equipment required, high production cost and difficulty in mass production.

[0005] In view of these problems, the present invention provides a method for preparing an anti-counterfeiting micro-nanostructure pattern based on nanoimprint technology, comprising the following steps:

[0006] (1) Pre-treating the substrate surface;

[0007] (2) First, LOR glue (lift-off resist) is spin-coated on the surface of the substrate and heated and cured to form a bottom layer;

[0008] (3) Spin-coating a UV photoresist on the bottom layer and curing it after UV exposure;

[0009] (4) preparing a polydimethylsiloxane soft template; then placing the polydimethylsiloxane soft template on a substrate coated with a photoresist, and after ultraviolet exposure treatment, separating the soft template from the substrate to obtain a substrate coated with a photoresist printed with a micro-nano structure pattern;

[0010] (5) using reactive ion etching technology to etch the UV photoresist to expose the LOR glue bottom layer;

[0011] (6) Using UV photoresist as a mask layer, etching the LOR glue;

[0012] (7) Using UV photoresist and LOR glue as masks, the substrate is etched to transfer the micro-nanostructure pattern to the substrate.

[0013] As a preferred embodiment of the technical solution of the present invention, in step (1), the substrate is selected from silicon, silicon dioxide or ITO conductive glass.

[0014] As a preferred embodiment of the technical solution of the present invention, in step (1), the pretreatment is to ultrasonically clean the substrate, blow dry the substrate surface with high-purity nitrogen after cleaning, and then dry it to completely remove the residual solvent on the substrate surface.

[0015] As a preferred embodiment of the technical solution of the present invention, in step (2), the thickness of the LOR glue is 100 to 400 nm.

[0016] As a preferred embodiment of the technical solution of the present invention, in step (2), the curing temperature of the LOR glue is 90-120°C.

[0017] As a preferred embodiment of the technical solution of the present invention, in step (2), the curing time of the LOR glue is 5 to 10 minutes.

[0018] As a preferred embodiment of the technical solution of the present invention, in step (2), the LOR glue is a thermoplastic photoresist.

[0019] Further preferably, the thermoplastic photoresist is selected from polymethacrylate (PMMA), polystyrene or polycarbonate.

[0020] As a preferred embodiment of the technical solution of the present invention, in step (3), the ultraviolet photoresist is selected from Amonil photoresist.

[0021] Further preferably, the UV photoresist is selected from Amonil SS4 or Amonil SS10.

[0022] As a preferred embodiment of the technical solution of the present invention, in step (3), the thickness of the ultraviolet photoresist is 70 to 370 nm, more preferably 170 to 370 nm.

[0023] As a preferred embodiment of the technical solution of the present invention, in step (3), the rotation speed of the spin coating is 500 to 5000 rpm.

[0024] As a preferred embodiment of the technical solution of the present invention, in step (3), the spin coating time is 10 to 50 seconds.

[0025] As a preferred embodiment of the technical solution of the present invention, in step (3), the curing temperature of the ultraviolet photoresist is 80-120°C.

[0026] As a preferred embodiment of the technical solution of the present invention, in step (3), the curing time of the ultraviolet photoresist is 0.5 to 1 min.

[0027] As a preferred embodiment of the technical solution of the present invention, in step (4), the polydimethylsiloxane soft template is prepared by mixing a curing agent and a polydimethylsiloxane prepolymer.

[0028] As a preferred embodiment of the technical solution of the present invention, in step (4), the weight ratio of the curing agent to the polydimethylsiloxane prepolymer is preferably 1:(3-15), and more preferably 1:(3-10).

[0029] As a preferred embodiment of the technical solution of the present invention, in step (4), the curing agent and the prepolymer are polydimethylsiloxane RTV 615B and polydimethylsiloxane RTV 615A respectively.

[0030] As a preferred embodiment of the technical solution of the present invention, in step (4), the curing temperature after the curing agent and the prepolymer are mixed is 40 to 120°C.

[0031] As a preferred embodiment of the technical solution of the present invention, in step (4), the curing time is 10 to 30 hours.

[0032] As a preferred embodiment of the technical solution of the present invention, in step (4), the conditions of the ultraviolet exposure treatment are: the air pressure of the ultraviolet exposure is 0 to 50 psi; and the ultraviolet exposure time is 5 to 10 minutes.

[0033] As a preferred embodiment of the technical solution of the present invention, in step (5), the etching gas used to etch the ultraviolet photoresist using reactive ion etching technology is CHF 3 With O 2 .

[0034] More preferably, CHF 3 With O 2 The flow ratio is (4-10):(1-5), more preferably (6-10):(1-5);

[0035] As a preferred embodiment of the technical solution of the present invention, in step (5), the etching power of the ultraviolet photoresist is 12 to 30 W and the pressure is 5 to 7 mtorr using reactive ion etching technology; more preferably, the etching power is 12 to 25 W and / or the pressure is 7 mtorr.

[0036] As a preferred embodiment of the technical solution of the present invention, in step (6), the conditions for etching the LOR glue using reactive ion etching technology are: the etching gas is O 2 .

[0037] Further preferably, O 2 The flow rate is 10~30sccm.

[0038] As a preferred embodiment of the technical solution of the present invention, in step (6), the etching power of etching the LOR glue using reactive ion etching technology is 20 to 50 W and the pressure is 20 to 50 mtorr.

[0039] As a preferred embodiment of the technical solution of the present invention, the micro-nano structure pattern can be used in the field of anti-counterfeiting.

[0040] The beneficial effects of the present invention are that the method requires simple equipment, short cycle, simple process and low cost, and can prepare anti-counterfeiting micro-nano structure patterns with high aspect ratio, large area and controllable structural size precision within a large scale range. Under the preferred etching conditions of the present invention, the aspect ratio of the obtained micro-nano structure pattern can reach 6 to 10. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 This is a polydimethylsiloxane soft template image obtained during the preparation process of Example 1;

[0042] Figure 2 A scanning electron microscope image of the nanohole array pattern prepared in Example 1;

[0043] Figure 3 A scanning electron microscope image of the nano-cylinder array pattern prepared in Example 2;

[0044] Figure 4 This is a scanning electron microscope image of the nanograting array prepared in Example 3. DETAILED DESCRIPTION

[0045] As described above, the purpose of the present invention is to provide an anti-counterfeiting micro-nanostructure pattern with controllable structural size prepared based on nanoimprinting technology. This method can obtain a large-area micro-nanostructure pattern with controllable structural size accuracy within a large scale range, and the obtained micro-nanostructure pattern has a high aspect ratio.

[0046] Among them, in a specific embodiment of the present invention, a method for preparing an anti-counterfeiting micro-nanostructure pattern based on nanoimprint technology is provided, comprising the following steps:

[0047] (1) ultrasonically cleaning the substrate, drying the surface of the substrate with high-purity nitrogen after cleaning, and baking the substrate in an oven to completely remove the residual solvent on the surface of the substrate, wherein the substrate is silicon, silicon dioxide or ITO conductive glass;

[0048] (2) firstly spin-coating LOR glue on the surface of the substrate, the thickness of the LOR glue is 100 to 400 nm, and heating and curing to form a bottom layer, the LOR glue is preferably a thermoplastic photoresist, and the thermoplastic photoresist is selected from polymethacrylate, polystyrene or polycarbonate;

[0049] (3) Spin-coating ultraviolet photoresist on the bottom layer, the thickness of the ultraviolet photoresist is 70-370 nm, and curing after ultraviolet light exposure. The ultraviolet photoresist is preferably Amonil photoresist, and more preferably Amonil SS4 or Amonil SS10.

[0050] (4) The polydimethylsiloxane RTV 615B curing agent and the polydimethylsiloxane RTV 615A prepolymer are mixed in a weight ratio of 1: (3 to 15) to prepare a polydimethylsiloxane soft template, and the curing temperature is 40 to 120° C.; the curing time is 10 to 30 hours.

[0051] Then, the polydimethylsiloxane soft template is placed on a substrate coated with photoresist. After ultraviolet exposure treatment, the soft template is separated from the substrate to obtain a substrate coated with photoresist printed with a micro-nano structure pattern. The air pressure of ultraviolet exposure is 0-50psi; the ultraviolet exposure time is 5-10min.

[0052] (5) Use reactive ion etching technology to etch the UV photoresist to expose the LOR glue bottom layer. The conditions for etching the UV photoresist are: the etching gas is CHF 3 With O 2 ; preferably, CHF 3 With O 2 The flow ratio is (4-10): (1-5); further preferably, the etching power is 12-30W, and the pressure is 5-7mtorr;

[0053] (6) Then, the UV photoresist is used as a mask layer to etch the LOR glue. The etching gas is O 2 ; Preferably, O 2 The flow rate is 10-30sccm;

[0054] (7) Finally, the substrate is etched using the UV photoresist and LOR resin as masks to transfer the micro-nanostructure pattern to the substrate.

[0055] The experimental materials and instrument information used in the following examples are shown in Table 1:

[0056] Table 1 Information of experimental materials and instruments

[0057]

[0058]

[0059] In order to better understand the present invention, the present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0060] Example 1

[0061] 1) The Si substrate was cleaned with acetone, alcohol, and deionized water in sequence. After cleaning, the Si surface was dried with high-purity nitrogen. The sample was then placed in an oven at 50°C and baked for 2 h. The substrate was then taken out and cooled at room temperature.

[0062] 2) Mix polydimethylsiloxane curing agent RTV 615B and polydimethylsiloxane prepolymer RTV 615A in a weight ratio of 1:3, and after vacuum degassing, cast on the pre-treated imprinting master plate; after exhausting all bubbles, cure in an oven at 40°C for 30 hours; after curing, cool to room temperature, and peel it from the master plate to obtain an imprinted soft film. The photo of the obtained nanoimprint soft film is shown in Figure 1 shown.

[0063] 3) The pretreated Si substrate was adsorbed on a spin coater, and a layer of PMMA was first spin-coated with a thickness of 100 nm, and then baked on a hot plate at 90°C for 10 min; then, the UV photoresist Amonil SS4 was dropped on the surface of the PMMA glue with a dropper, and the spin coater was rotated at a speed of 500 rpm for 50 s. The thickness of the UV photoresist was 370 nm, and then the substrate with the UV photoresist spin-coated was placed on a hot plate at 80°C and heated for 1 min.

[0064] 4) The polydimethylsiloxane soft template is gently placed on the Si substrate coated with the photoresist, and then placed in a UV nanoimprinter with an air pressure of 0 psi and a UV exposure time of 10 min. After curing, the polydimethylsiloxane template is separated from the substrate.

[0065] 5) Use CHF first 3 and O 2 As a reactive gas, the residual UV photoresist on the substrate obtained after the imprinting is etched. The etching conditions are: CHF 3 The flow rate is 20 sccm, O 2 The flow rate is 2sccm, the power is 12W, and the pressure is 7mtorr. After etching the remaining UV resist, use O 2 Etch the PMMA glue and transfer the micro-nano structure on the UV photoresist to the PMMA glue. The etching conditions are: 2 Flow rate 10sccm, power 50W, pressure 20mtorr. Finally, use CHF3 and SF 6 The reactive ion pair etches the silicon substrate to directly transfer the pattern onto the silicon substrate. The SEM photograph of the obtained nanopore array pattern is as Figure 2 shown, with a magnification of 100,000 times. The diameter of the pores is 100 nm, the gap between the pores is 50 nm, and the aspect ratio is 8.

[0066] Example 2

[0067] 1) Clean the SiO 2 substrate successively with acetone, alcohol, and deionized water. After cleaning, dry the surface of the SiO 2 with high-purity nitrogen, and then place the sample in an oven at 200 °C for 0.5 h, and take it out to cool the substrate at room temperature.

[0068] 2) Mix the polydimethylsiloxane curing agent RTV 615B and the polydimethylsiloxane prepolymer RTV 615A according to a weight ratio of 1:10. After vacuum degassing, cast it on the pre-treated imprint master; after exhausting the bubbles, cure it in an oven at 120 °C for 10 h; after curing, cool it to room temperature.

[0069] 3) Adsorb the pre-treated SiO 2 substrate on a spin coater. First, spin coat a layer of PMMA with a thickness of 400 nm and bake it on a hot plate at a temperature of 120 °C for 5 min; then use a dropper to drop the ultraviolet photoresist Amonil SS4 on the surface of the PMMA film, rotate the spin coater at a rotation speed of 5000 rpm for 10 s, the thickness of the ultraviolet photoresist is 170 nm, and then place the substrate with the spin-coated ultraviolet photoresist on a hot plate at 120 °C and heat it for 30 s.

[0070] 4) Gently place the polydimethylsiloxane soft template on the SiO 2 substrate coated with photoresist, and then put it into an ultraviolet nanoimprinting machine. The air pressure is 50 psi, and the ultraviolet exposure time is 5 min. After curing, separate the polydimethylsiloxane soft template from the substrate.

[0071] 5) First, use CHF 3 and O 2 as reaction gases to etch the residual ultraviolet photoresist on the substrate obtained after imprinting. The etching conditions are: CHF 3 flow rate 12 sccm, O 2 flow rate 10 sccm, power 25 W, pressure 7 mtorr. After etching the residual ultraviolet photoresist, use O 2 to etch the PMMA film and transfer the micro-nano structure on the UV film to the PMMA film. The etching conditions are: O 2 flow rate 30 sccm, power 20 W, pressure 50 mtorr. Finally, use CHF3 and O 2 Reactive ion pairs SiO 2 The substrate is etched and the pattern is directly transferred to the SiO 2 Substrate. The SEM image of the obtained nano-cylinder pattern array is shown in Figure 3 As shown in the figure, the magnification is 50,000 times, and it can be seen that the prepared nanopattern has uniform size and the edge contour of the pattern is complete and clear. The diameter of the nanocylinder is 700nm, the gap between the nanocylinders is 300nm, and the aspect ratio is 10.

[0072] Example 3

[0073] 1) The ITO conductive glass substrate was cleaned with acetone, alcohol and deionized water in turn. After cleaning, the surface of the ITO conductive glass was blown dry. Then, the sample was placed in an oven at 150° C. and baked for 1 h. The substrate was taken out and cooled at room temperature.

[0074] 2) Mix polydimethylsiloxane curing agent RTV 615B and polydimethylsiloxane prepolymer RTV 615A in a weight ratio of 1:5, and after vacuum degassing, cast on the pre-treated imprinting mother board; after exhausting all bubbles, cure in an oven at 100°C for 14 hours; and cool to room temperature after curing.

[0075] 3) The pretreated ITO conductive glass substrate was adsorbed on the spin coater, and PMMA was first spin-coated with a thickness of 250 nm and baked at a hot plate temperature of 100°C for 8 min; then, the UV photoresist Amonil SS10 was dropped on the surface of the PMMA glue with a dropper, and the spin coater was rotated at a speed of 3000 rpm for 25 seconds. The thickness of the UV photoresist was 100 nm, and then the substrate with the spin-coated UV photoresist was placed on a hot plate at 100°C and heated for 40 seconds.

[0076] 4) The polydimethylsiloxane soft template is gently placed on the ITO substrate coated with the photoresist, and then placed in a UV nanoimprinter with an air pressure of 30 psi and a UV exposure time of 7 min. After curing, the polydimethylsiloxane soft template is separated from the substrate.

[0077] 5) Use CHF first 3 and O 2 As a reactive gas, the residual UV photoresist on the substrate obtained after the imprinting is etched. The etching conditions are: CHF 3 Flow rate 15sccm, O 2 Flow rate 7sccm, power 16W, pressure 5mtorr. After etching the residual UV resist, use O 2 Etch the LOR glue and transfer the micro-nano structure on the UV glue to the LOR glue. The etching conditions are: 2Flow rate 20sccm, power 40W, pressure 35mtorr. Finally, use CF 4 The ITO substrate is etched by Ar reactive ions and the pattern is directly transferred to the ITO substrate. Figure 4 The SEM photo of the final nano-grating structure pattern is shown, with a magnification of 40,000 times. It can be seen that the size of the prepared nano-grating pattern is uniform, the sidewall profile is steep and complete, the line width is 800nm, the gap between the lines is 700nm, and the aspect ratio is 6.

[0078] Example 4

[0079] 1) Use acetone, alcohol and deionized water to clean SiO 2 After cleaning, blow dry the SiO 2 The sample was then placed in an oven at 200 °C for 0.5 h and the substrate was cooled at room temperature.

[0080] 2) Mix polydimethylsiloxane curing agent RTV 615B and polydimethylsiloxane prepolymer RTV 615A in a weight ratio of 1:10, degas in vacuum, and cast on a pre-treated imprinting master plate; after exhausting all bubbles, cure in an oven at 120° C. for 10 hours, and cool to room temperature after curing.

[0081] 3) The pretreated SiO 2 The substrate was adsorbed on the spin coater, and a layer of PMMA was first spin-coated with a thickness of 400 nm and baked on a hot plate at 120°C for 5 min. Then, the UV photoresist Amonil SS4 was dropped on the surface of the PMMA glue with a dropper, and the spin coater was rotated at a speed of 5000 rpm for 10 seconds. The thickness of the UV photoresist was 170 nm, and then the substrate with the UV photoresist spin-coated was placed on a hot plate at 120°C and heated for 30 seconds.

[0082] 4) Gently place the polydimethylsiloxane soft template on the SiO 2 The substrate was then placed in a UV nanoimprinter with an air pressure of 50 psi and a UV exposure time of 5 min. After curing, the polydimethylsiloxane soft template was separated from the substrate.

[0083] 5) Use CHF first 3 and O 2 As a reactive gas, the residual UV photoresist on the substrate obtained after the imprinting is etched. The etching conditions are: CHF 3 Flow rate 12sccm, O 2 Flow rate 10sccm, power 10W, pressure 8mtorr. After etching the residual UV resist, use O 2Etch the PMMA glue and transfer the micro-nano structure on the UV glue to the PMMA glue. The etching conditions are: 2 Flow rate 30sccm, power 20W, pressure 50mtorr. Finally, use CHF 3 and O 2 Reactive ion pairs SiO 2 The substrate is etched and the pattern is directly transferred to the SiO 2 The results show that when the etching power and pressure are reduced by reactive ion etching, the contour of the obtained pattern is incomplete and the aspect ratio of the obtained pattern is 3.

[0084] Comparative Example 1

[0085] 1) Use acetone, alcohol and deionized water to clean SiO 2 After cleaning, blow dry the SiO 2 The sample was then placed in an oven at 200 °C for 0.5 h and the substrate was cooled at room temperature.

[0086] 2) Mix polydimethylsiloxane curing agent RTV 615B and polydimethylsiloxane prepolymer RTV 615A in a weight ratio of 1:10, degas in vacuum, and cast on a pre-treated imprinting master plate; after exhausting all bubbles, cure in an oven at 120° C. for 10 hours; and cool to room temperature after curing.

[0087] 3) The pretreated SiO 2 The substrate was adsorbed on the spin coater, and a layer of PMMA was first spin-coated with a thickness of 400 nm and baked on a hot plate at 120°C for 5 min. Then, SU-8 photoresist was dropped on the surface of PMMA glue with a dropper, and the spin coater was rotated at 3000 rpm for 10 s. The thickness of SU-8 photoresist was 1 μm, and then the substrate with SU-8 photoresist spin-coated was placed on a hot plate at 95°C and heated for 60 s.

[0088] 4) Gently place the polydimethylsiloxane soft template on the SiO 2 The substrate was then placed in a UV nanoimprinter with an air pressure of 50 psi and a UV exposure time of 5 min. After curing, the polydimethylsiloxane soft template was separated from the substrate.

[0089] 5) First use O 2 As a reaction gas, the SU-8 photoresist remaining on the substrate after the imprinting is etched. The etching conditions are: 2 The flow rate is 25sccm, the power is 80W, and the pressure is 40mtorr. After etching the residual UV resist, use O 2 Etch the PMMA glue and transfer the micro-nano structure on the UV glue to the PMMA glue. The etching conditions are:2 The flow rate is 30sccm, the power is 20W, and the pressure is 50mtorr. Finally, CHF 3 and O 2 Reactive ion pairs SiO 2 The substrate is etched and the pattern is directly transferred to the SiO 2 The results show that the size of the nano-patterns prepared by using SU-8 UV photoresist is significantly different from the size of the patterns on the imprinting master, especially for structures with smaller size (less than 100 nm), the aspect ratio of the obtained pattern is 2.

[0090] The above 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 variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing micro-nanostructure patterns based on nanoimprint technology, It is characterized in that The steps include: (1) Pre-treating the substrate surface; (2) spin coating LOR glue on the surface of the substrate and heating and curing it to form a bottom layer; the curing temperature of the LOR glue is 90-120° C.; the LOR glue is polymethacrylate; (3) Spin-coating ultraviolet photoresist on the bottom layer and subjecting it to heating treatment; the heating temperature of the ultraviolet photoresist is 80 to 120° C.; the ultraviolet photoresist is Amonil photoresist; (4) preparing a polydimethylsiloxane soft template, placing the polydimethylsiloxane soft template on a substrate coated with a photoresist, and after ultraviolet exposure treatment, separating the soft template from the substrate to obtain a substrate coated with a photoresist printed with a micro-nano structure pattern; (5) Using reactive ion etching technology to etch the UV photoresist to expose the LOR glue bottom layer; the conditions for etching the UV photoresist using reactive ion etching technology are: the etching gas is CHF 3 With O 2 ;CHF 3 With O 2 The flow ratio is 4-10:1-5; the etching power is 12-30W, and the pressure is 5-7mtorr; (6) Using the UV photoresist as a mask layer, etching the LOR glue; the conditions for etching the LOR glue using the reactive ion etching technology are: the etching gas is O 2 ;O 2 The flow rate is 10-30sccm; the etching power is 20-50W, and the pressure is 20-50mtorr; (7) Using UV photoresist and LOR glue as masks, the substrate is etched to transfer the micro-nanostructure pattern to the substrate.

2. The preparation method according to claim 1, It is characterized in that In step (1), the substrate is selected from silicon, silicon dioxide or ITO conductive glass.

3. The preparation method according to claim 1, It is characterized in that In step (1), the pretreatment is to ultrasonically clean the substrate, blow dry the substrate surface with high-purity nitrogen after cleaning, and then dry it to completely remove the residual solvent on the substrate surface.

4. The preparation method according to claim 2, It is characterized in that In step (1), the pretreatment is to ultrasonically clean the substrate, blow dry the substrate surface with high-purity nitrogen after cleaning, and then dry it to completely remove the residual solvent on the substrate surface.

5. The preparation method according to claim 1, It is characterized in that The thickness of the LOR glue is 100 to 400 nm.

6. The preparation method according to claim 2, It is characterized in that The thickness of the LOR glue is 100 to 400 nm.

7. The preparation method according to claim 3, It is characterized in that The thickness of the LOR glue is 100 to 400 nm.

8. The preparation method according to claim 1, It is characterized in that In step (2), the curing time is 5 to 10 minutes.

9. The preparation method according to claim 2, It is characterized in that In step (2), the curing time is 5 to 10 minutes.

10. The preparation method according to claim 3, It is characterized in that In step (2), the curing time is 5 to 10 minutes.

11. The preparation method according to claim 5, It is characterized in that In step (2), the curing time is 5 to 10 minutes.

12. The preparation method according to claim 1, It is characterized in that In step (3), the ultraviolet photoresist is selected from Amonil SS4 or Amonil SS10.

13. The preparation method according to any one of claims 1 to 12, It is characterized in that In step (3), the rotation speed of the spin coating is 500 to 5000 rpm.

14. The preparation method according to any one of claims 1 to 12, It is characterized in that In step (3), the spin coating time is 10 to 50 seconds.

15. The preparation method according to claim 13, It is characterized in that In step (3), the spin coating time is 10 to 50 seconds.

16. The preparation method according to any one of claims 1 to 12, It is characterized in that In step (3), the thickness of the ultraviolet photoresist is 70 to 370 nm.

17. The preparation method according to claim 13, It is characterized in that In step (3), the thickness of the ultraviolet photoresist is 70 to 370 nm.

18. The preparation method according to claim 14, It is characterized in that In step (3), the thickness of the ultraviolet photoresist is 70 to 370 nm.

19. The preparation method according to any one of claims 1 to 12, It is characterized in that In step (3), the heating time is 0.5 to 1 min.

20. The preparation method according to claim 13, It is characterized in that In step (3), the heating time is 0.5 to 1 min.

21. The preparation method according to claim 14, It is characterized in that In step (3), the heating time is 0.5 to 1 min.

22. The preparation method according to claim 16, It is characterized in that In step (3), the heating time is 0.5 to 1 min.

23. The preparation method according to any one of claims 1 to 12, It is characterized in that In step (4), the polydimethylsiloxane soft template is prepared by mixing a curing agent with a polydimethylsiloxane prepolymer.

24. The preparation method according to claim 13, It is characterized in that In step (4), the polydimethylsiloxane soft template is prepared by mixing a curing agent with a polydimethylsiloxane prepolymer.

25. The preparation method according to claim 14, It is characterized in that In step (4), the polydimethylsiloxane soft template is prepared by mixing a curing agent with a polydimethylsiloxane prepolymer.

26. The preparation method according to claim 16, It is characterized in that In step (4), the polydimethylsiloxane soft template is prepared by mixing a curing agent with a polydimethylsiloxane prepolymer.

27. The preparation method according to claim 19, It is characterized in that In step (4), the polydimethylsiloxane soft template is prepared by mixing a curing agent with a polydimethylsiloxane prepolymer.

28. The preparation method according to claim 23, It is characterized in that The weight ratio of the curing agent to the polydimethylsiloxane prepolymer is 1:(3-15).

29. The preparation method according to claim 23, It is characterized in that The curing agent and prepolymer are polydimethylsiloxane RTV 615B and polydimethylsiloxane RTV 615A respectively.

30. The preparation method according to claim 28, It is characterized in that The curing agent and prepolymer are polydimethylsiloxane RTV 615B and polydimethylsiloxane RTV 615A respectively.

31. The preparation method according to claim 23, It is characterized in that The curing temperature after the curing agent and the prepolymer are mixed is 40 to 120° C.; the curing time is 10 to 30 hours.

32. The preparation method according to claim 28, It is characterized in that The curing temperature after the curing agent and the prepolymer are mixed is 40 to 120° C.; the curing time is 10 to 30 hours.

33. The preparation method according to claim 29, It is characterized in that The curing temperature after the curing agent and the prepolymer are mixed is 40 to 120° C.; the curing time is 10 to 30 hours.

34. The preparation method according to any one of claims 1 to 12, It is characterized in that In step (4), the conditions of the ultraviolet exposure treatment are: the air pressure of the ultraviolet exposure is 0 to 50 psi; and the ultraviolet exposure time is 5 to 10 minutes.

35. The preparation method according to claim 13, It is characterized in that In step (4), the conditions of the ultraviolet exposure treatment are: the air pressure of the ultraviolet exposure is 0 to 50 psi; and the ultraviolet exposure time is 5 to 10 minutes.

36. The preparation method according to claim 14, It is characterized in that In step (4), the conditions of the ultraviolet exposure treatment are: the air pressure of the ultraviolet exposure is 0 to 50 psi; and the ultraviolet exposure time is 5 to 10 minutes.

37. The preparation method according to claim 16, It is characterized in that In step (4), the conditions of the ultraviolet exposure treatment are: the air pressure of the ultraviolet exposure is 0 to 50 psi; and the ultraviolet exposure time is 5 to 10 minutes.

38. The preparation method according to claim 19, It is characterized in that In step (4), the conditions of the ultraviolet exposure treatment are: the air pressure of the ultraviolet exposure is 0 to 50 psi; and the ultraviolet exposure time is 5 to 10 minutes.

39. The preparation method according to claim 23, It is characterized in that In step (4), the conditions of the ultraviolet exposure treatment are: the air pressure of the ultraviolet exposure is 0 to 50 psi; and the ultraviolet exposure time is 5 to 10 minutes.

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