Photoresist for nanoimprinting process and preparation method and application thereof

Abstract

The present invention relates to the field of nanoimprint technology, and in particular to a photoresist for nanoimprint technology, and a preparation method and application thereof. The photoresist for nanoimprint technology comprises 85% to 99.9% of a colloidal matrix and 0.1% to 15% of a silicon-containing acrylate coupling agent by mass percentage. The present invention introduces a silicon-containing acrylate coupling agent into the colloidal matrix, wherein Si-OCH3 is unstable and easily hydrolyzed into Si-OH groups, which can form hydrogen bonds with hydroxyl groups in the silicon substrate, thereby increasing the adhesion between the photoresist and the substrate; and, after the photoresist forms a film, the silicon hydroxyl groups and silicon methoxy groups therein can improve the anti-dry etching performance of the photoresist; furthermore, by adding low surface energy silicon oxygen groups in the silane coupling agent, the silicon oxygen groups contained in the upper part of the film are easily enriched on the air surface during spin coating, which is beneficial to reducing the surface energy of the photoresist, making it easier to demold after imprinting.

Description

Technical Field

[0001] The present invention relates to the field of nanoimprint technology, and in particular to a photoresist used in a nanoimprint process and a preparation method and application thereof. Background Art

[0002] With the progress and development of science and technology, people have found from theoretical and experimental research that when many materials are processed into shapes with nanoscale range, they will show completely different properties from bulk materials. These special properties show exciting application prospects to people. In the process of developing ultra-large-scale integrated circuit process technology, people have developed some technologies that can perform nanoscale processing, such as electron beam and X-ray exposure, focused ion beam processing, scanning probe etching technology, etc. However, the disadvantages of these technologies are expensive equipment and low output, so the product price is high. The production of commercial products must be cheap, easy to operate, industrially mass-produced, and highly repeatable; for nanoscale products, it must also be able to maintain the accuracy and resolution of its unique graphics. In response to this challenge, the "Nanostructure Laboratory of the University of Minnesota" in the United States has conducted pioneering research since 1995. They proposed and demonstrated a new technology called "nanoimprint lithography".

[0003] Nanoimprint technology has the advantages of high output, low cost and simple process, and is an important manufacturing technology for nano-sized electronic devices. However, the important indicators of nanoimprint that affect its production practice are the dry etching resistance and the morphology uniformity of the pattern after imprinting. The important factor affecting the morphology uniformity is the ease of demolding between the photoresist and the plate.

[0004] Acrylate photoresist systems have advantages such as strong photosensitivity, but acrylate photoresists have poor dry etching resistance and adhesion properties and cannot effectively meet the requirements of nanoimprint technology.

[0005] In view of this, the present invention is proposed. Summary of the invention

[0006] The first purpose of the present invention is to provide a photoresist for nanoimprinting process, so as to solve the technical problem that the photoresist in the prior art cannot meet the requirements of nanoimprinting in terms of resistance to dry etching, adhesion and other aspects of performance.

[0007] The second object of the present invention is to provide a method for preparing a photoresist for nanoimprinting process.

[0008] A third object of the present invention is to provide an application of a photoresist for nanoimprinting process in nanoimprinting.

[0009] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are particularly adopted:

[0010] The photoresist used in the nano-imprinting process comprises 85% to 99.9% of a colloid matrix and 0.1% to 15% of a silicon-containing acrylate coupling agent in terms of mass percentage.

[0011] The present invention introduces a silicon-containing acrylate coupling agent into a colloidal matrix, wherein Si-OCH3 is unstable and easily hydrolyzed into Si-OH groups, which can form hydrogen bonds with hydroxyl groups in a silicon substrate, thereby increasing the adhesion between the photoresist and the substrate. Moreover, after the photoresist forms a film, the etching resistance of pure organic materials is relatively weak due to the low CC bond and CH bond energies. The etching resistance of organic silicon materials is relatively strong due to the high-energy Si-O group bonds, so the silicon hydroxyl groups and silicon methoxy groups in the colloid after addition can improve the anti-dry etching performance of the photoresist.

[0012] In a specific embodiment of the present invention, the silicon-containing acrylic coupling agent is selected from any one or more of γ-(methacryloyloxy)propyltrimethoxysilane (i.e., KH570), γ-(methacryloyloxy)propyltriethoxysilane, γ-(methacryloyloxy)propyltriisopropoxysilane, propyltrimethoxysilane methacrylate, propyltrimethoxysilane acrylate, propyldimethoxymethylsilane methacrylate, propyldimethoxymethylsilane acrylate, methyltrimethoxysilane methacrylate, methyltrimethoxysilane acrylate, methyldimethoxymethylsilane methacrylate and methyldimethoxysilane acrylate.

[0013] In a specific embodiment of the present invention, the colloidal matrix comprises the following components in parts by weight:

[0014] 10 to 25 parts of acrylate, 1 to 6 parts of photoinitiator, 5 to 15 parts of active diluent and 30 to 70 parts of solvent.

[0015] In a specific embodiment of the present invention, the photoinitiator includes any one or more of 2-methyl-1-(4-methylthiophenyl)-2-morpholine-1-propanone, isopropyl thioxanthone, 2,4-diethyl thioxanthone, 2,4,6-trimethylbenzoyldiphenyl phosphine oxide, 4-(N,N'-dimethyl-amino) benzophenone, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl 1-propanone and benzophenone.

[0016] In a specific embodiment of the present invention, the reactive diluent includes any one or more of isobornyl acrylate, tripropylene glycol diacrylate, trimethylolpropane triacrylate, dimethylolpropane tetraacrylate and 1,6-hexanediol diacrylate.

[0017] In a specific embodiment of the present invention, the solvent includes any one or more of propylene glycol monomethyl ether, propylene glycol monobutyl ether, diethylene glycol dimethyl ether, diethylene glycol monomethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol monomethyl ether, propylene glycol methyl ether acetate, butyl acetate and butyl lactate.

[0018] The present invention also provides a method for preparing the above-mentioned photoresist for nanoimprinting process, comprising the following steps:

[0019] Mix the components in proportion.

[0020] The invention also provides application of the photoresist used in the nanoimprint process in the nanoimprint process.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] (1) The present invention provides a photoresist for nanoimprinting process with excellent adhesion and anti-dry etching performance by introducing a silicon-containing acrylate coupling agent into a colloidal matrix; furthermore, by adding low surface energy siloxy groups in the silicon-containing acrylate coupling agent, the siloxy groups contained in the upper part of the film are easily enriched on the air surface during spin coating, which is beneficial to reducing the surface energy of the photoresist and making it easier to demold after imprinting.

[0023] (2) The colloidal matrix of the photoresist of the present invention is an acrylate system, which has the advantages of strong photosensitivity, simple preparation, low raw material cost, low softening point after curing, good fluidity and easy imprinting and molding. DETAILED DESCRIPTION

[0024] The technical scheme of the present invention will be clearly and completely described below in conjunction with specific embodiments, but it will be appreciated by those skilled in the art that the following described embodiments are part of embodiments of the present invention, rather than all embodiments, and are only used to illustrate the present invention, and should not be considered as limiting the scope of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work, all belong to the scope of protection of the present invention. If specific conditions are not indicated in the embodiments, they are carried out according to normal conditions or conditions recommended by the manufacturer. If the manufacturer is not indicated in the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0025] The photoresist used in the nano-imprinting process comprises 85% to 99.9% of a colloid matrix and 0.1% to 15% of a silicon-containing acrylate coupling agent in terms of mass percentage.

[0026] The present invention introduces a silicon-containing acrylate coupling agent into a colloidal matrix, wherein the Si-OCH3 is unstable and easily hydrolyzed into a Si-OH group, which can form a hydrogen bond with the hydroxyl group in the silicon substrate, thereby increasing the adhesion between the photoresist and the substrate; and after the photoresist forms a film, the silicon hydroxyl group and silicon methoxy group therein can improve the anti-dry etching performance of the photoresist.

[0027] For example, in different embodiments, in the photoresist, the mass percentage of the silicon-containing acrylate coupling agent can be 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15% and the like; the mass percentage of the colloidal matrix can be 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, 99.5%, 99.9% and the like.

[0028] In a specific embodiment of the present invention, the photoresist comprises 88% to 99% of the colloidal matrix and 1% to 12% of the silicon-containing acrylate coupling agent by mass percentage. Preferably, the photoresist comprises 92% to 95% of the colloidal matrix and 5% to 8% of the silicon-containing acrylate coupling agent by mass percentage.

[0029] In a specific embodiment of the present invention, the silicon-containing acrylate coupling agent is selected from any one or more of propyltrimethoxysilyl methacrylate, propyltrimethoxysilyl acrylate, propyldimethoxymethylsilyl methacrylate, propyldimethoxymethylsilyl acrylate, methyltrimethoxysilyl methacrylate, methyltrimethoxysilyl acrylate, methyldimethoxymethylsilyl methacrylate and methyldimethoxysilyl acrylate.

[0030] In a specific embodiment of the present invention, the colloidal matrix comprises the following components in parts by weight:

[0031] 10 to 25 parts of acrylate, 1 to 6 parts of photoinitiator, 5 to 15 parts of active diluent and 30 to 70 parts of solvent.

[0032] For example, in different embodiments, in the colloidal matrix, the amount of acrylate can be 10 parts, 12 parts, 15 parts, 18 parts, 20 parts, 22 parts, 25 parts, etc.; the amount of photoinitiator can be 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, etc.; the amount of active diluent can be 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, etc.; the amount of solvent can be 30 parts, 35 parts, 40 parts, 45 parts, 50 parts, 55 parts, 60 parts, 65 parts, 70 parts, etc.

[0033] In a specific embodiment of the present invention, the photoinitiator includes any one or more of 2-methyl-1-(4-methylthiophenyl)-2-morpholine-1-propanone, isopropyl thioxanthone, 2,4-diethyl thioxanthone, 2,4,6-trimethylbenzoyldiphenyl phosphine oxide, 4-(N,N'-dimethyl-amino) benzophenone, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl 1-propanone and benzophenone.

[0034] In a specific embodiment of the present invention, the reactive diluent includes any one or more of isobornyl acrylate, tripropylene glycol diacrylate, trimethylolpropane triacrylate, dimethylolpropane tetraacrylate and 1,6-hexanediol diacrylate.

[0035] In a specific embodiment of the present invention, the solvent includes any one or more of propylene glycol monomethyl ether, propylene glycol monobutyl ether, diethylene glycol dimethyl ether, diethylene glycol monomethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol monomethyl ether, propylene glycol methyl ether acetate, butyl acetate and butyl lactate.

[0036] The present invention also provides a method for preparing the above-mentioned photoresist for nanoimprinting process, comprising the following steps:

[0037] Mix the components in proportion.

[0038] The invention also provides application of the photoresist used in the nanoimprint process in the nanoimprint process.

[0039] Preferably, the nanoimprinting method comprises: coating the photoresist on the surface of a purified substrate and pre-baking it, then imprinting a pattern and curing the pattern, and then stripping the pattern to obtain an imprinted photoresist pattern.

[0040] More preferably, the nanoimprinting method specifically includes the following steps: coating the photoresist on a purified substrate, and pre-baking it on a hot plate at 110°C / 90s to remove residual solvent in the film, then imprinting the pattern and curing the imprinted pattern through i-line ultraviolet exposure on an exposure machine, and separating the imprint template from the photoresist to obtain an imprinted photoresist pattern.

[0041] Example 1

[0042] The photoresist for nanoimprinting process of this embodiment includes:

[0043] 1.0 g of propyltrimethoxysilyl methacrylate, 10.0 g of acrylate, 0.5 g of photoinitiator PI 907, 2.5 g of reactive diluent isobornyl acrylate, and 24.8 g of solvent propylene glycol methyl ether acetate.

[0044] The method for preparing the photoresist for the nanoimprint process comprises the following steps: mixing the above components, stirring and dissolving them fully, and filtering them with a filter with a pore size of 0.2 μm to obtain the photoresist.

[0045] The process of using the photoresist for nanoimprinting comprises the following steps:

[0046] The photoresist is coated on the purified substrate and pre-baked on a hot plate at 110°C / 90s to remove residual solvent in the film. The pattern is then imprinted and cured by i-line ultraviolet exposure on an exposure machine. The imprint template is separated from the photoresist to obtain an imprinted photoresist pattern.

[0047] Example 2

[0048] The photoresist for nanoimprinting process of this embodiment includes:

[0049] 0.5 g of propyltrimethoxysilane acrylate, 5.0 g of acrylate, 3.0 g of photoinitiator isopropyl thioxanthone, 7.0 g of active diluent tripropylene glycol diacrylate, and 35.0 g of solvent propylene glycol monomethyl ether.

[0050] The method for preparing the photoresist for the nanoimprint process comprises the following steps: mixing the above components, stirring and dissolving them fully, and filtering them with a filter with a pore size of 0.2 μm to obtain the photoresist.

[0051] The process of using the photoresist for nanoimprinting comprises the following steps:

[0052] The photoresist is coated on the purified substrate and pre-baked on a hot plate at 110°C / 90s to remove residual solvent in the film. The pattern is then imprinted and cured by i-line ultraviolet exposure on an exposure machine. The imprint template is separated from the photoresist to obtain an imprinted photoresist pattern.

[0053] Example 3

[0054] The photoresist for nanoimprinting process of this embodiment includes:

[0055] 5.5 g of propyl dimethoxymethylsilyl methacrylate, 12.5 g of acrylate, 1.0 g of photoinitiator 1-hydroxycyclohexyl phenyl ketone, 5.0 g of active diluent trimethylolpropane triacrylate, and 15.0 g of solvent diethylene glycol monomethyl ether.

[0056] The method for preparing the photoresist for the nanoimprint process comprises the following steps: mixing the above components, stirring and dissolving them fully, and filtering them with a filter with a pore size of 0.2 μm to obtain the photoresist.

[0057] The process of using the photoresist for nanoimprinting comprises the following steps:

[0058] The photoresist is coated on the purified substrate and pre-baked on a hot plate at 110°C / 90s to remove residual solvent in the film. The pattern is then imprinted and cured by i-line ultraviolet exposure on an exposure machine. The imprint template is separated from the photoresist to obtain an imprinted photoresist pattern.

[0059] Example 4

[0060] The photoresist for nanoimprinting process of this embodiment includes:

[0061] 4.0 g of propyl dimethoxymethylsilyl methacrylate, 10.0 g of acrylate, 2.0 g of photoinitiator 2,4-diethylthioxanthone, 6.0 g of active diluent dimethylolpropane tetraacrylate, and 30.0 g of solvent propylene glycol monobutyl ether.

[0062] The method for preparing the photoresist for the nanoimprint process comprises the following steps: the above components are mixed and fully stirred to dissolve, and then filtered with a filter with a pore size of 0.2 μm to obtain the photoresist.

[0063] The process of using the photoresist for nanoimprinting comprises the following steps: coating the photoresist on a purified substrate, pre-baking with a hot plate at 110° C. / 90 s to remove residual solvent in the film, then imprinting a pattern and curing the imprinted pattern through i-line ultraviolet exposure on an exposure machine, and separating the imprint template from the photoresist to obtain an imprinted photoresist pattern.

[0064] Example 5

[0065] The photoresist for nanoimprinting process of this embodiment includes:

[0066] 6.0 g of methyldimethoxysilyl acrylate, 10.0 g of acrylate, 2.5 g of photoinitiator PI 907, 7.5 g of reactive diluent isobornyl acrylate, and 25.0 g of solvent butyl lactate.

[0067] The method for preparing the photoresist for the nanoimprint process comprises the following steps: mixing the above components, stirring and dissolving them fully, and filtering them with a filter with a pore size of 0.2 μm to obtain the photoresist.

[0068] The process of using the photoresist for nanoimprinting comprises the following steps: coating the photoresist on a purified substrate, pre-baking with a hot plate at 110° C. / 90 s to remove residual solvent in the film, then imprinting a pattern and curing the imprinted pattern through i-line ultraviolet exposure on an exposure machine, and separating the imprint template from the photoresist to obtain an imprinted photoresist pattern.

[0069] Comparative Example 1

[0070] The photoresist provided in this comparative example includes:

[0071] Acrylate 10.0g, photoinitiator 0.5g, active diluent isobornyl acrylate 2.5g, solvent propylene glycol methyl ether acetate 24.8g.

[0072] The preparation method of the photoresist and the process for using it for nanoimprinting are exactly the same as those in Example 1.

[0073] Comparative Example 2

[0074] The components of the photoresist provided in this comparative example are substantially the same as those of Example 1, except that the amount of propyltrimethoxysilyl methacrylate is replaced with 9.0 g.

[0075] The preparation method of the photoresist and the process for using it for nanoimprinting are exactly the same as those in Example 1.

[0076] Comparative Example 3

[0077] The components of the photoresist provided in this comparative example are substantially the same as those in Example 1, except that the amount of acrylate is replaced with 20.0 g.

[0078] The preparation method of the photoresist and the process for using it for nanoimprinting are exactly the same as those in Example 1.

[0079] Experimental example

[0080] The photoresists prepared in the above embodiments and comparative examples were tested for adhesion, dry etching resistance and demolding difficulty. The results are shown in Table 1 below.

[0081] The criteria for determining the degree of demoulding difficulty are as follows: 1-easy demoulding; 2-relatively easy demoulding; 3-not easy demoulding; 4-relatively difficult demoulding; 5-difficult demoulding (i.e., from 1 to 5, from easy to difficult).

[0082] Adhesion is measured using the 100-grid scratch test method, which is performed in accordance with industry standards. Adhesion test results are marked with ASTM grades.

[0083] The dry etching performance is determined by using ICP dry etching to measure the column height H of the imprinted glue before etching. R, and the cone height H of the sapphire substrate surface obtained after etching S Then use H R :H S As a standard for measuring the dry-etching resistance of photoresist, the smaller the ratio is, the higher the height of the sapphire cone obtained under the same conditions, and the better the dry-etching resistance is.

[0084] Table 1 Performance test results of each group of photoresists

[0085]

[0086] It can be seen from Table 1 that the photoresist for nanoimprinting process provided by the present invention has excellent adhesion and dry etching resistance, and is easier to demold after imprinting.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A photoresist for nanoimprinting process, characterized in that: It includes 85% to 99.9% of a colloid matrix and 0.1% to 15% of a silicon-containing acrylate coupling agent by mass percentage; The silicon-containing acrylate coupling agent is selected from any one or more of propyl trimethoxysilyl methacrylate, propyl trimethoxysilyl acrylate, propyl dimethoxymethyl methacrylate, propyl dimethoxymethyl acrylate, methyl trimethoxysilyl methacrylate, methyl trimethoxysilyl acrylate, methyl dimethoxymethyl methacrylate and methyl dimethoxysilyl acrylate; The colloidal matrix comprises the following components by weight: 10-25 parts of acrylate, 1-6 parts of photoinitiator, 5-15 parts of reactive diluent and 30-70 parts of solvent; The photoinitiator includes any one of 2-methyl-1-(4-methylthiophenyl)-2-morpholine-1-propanone, isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 4-(N,N'-dimethyl-amino)benzophenone, 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-2-methyl-1-phenyl-1-propanone and benzophenone; The reactive diluent includes any one or more of isobornyl acrylate, tripropylene glycol diacrylate, trimethylolpropane triacrylate, dimethylolpropane tetraacrylate and 1,6-hexanediol diacrylate.

2. The photoresist for nanoimprinting process according to claim 1, characterized in that: The invention comprises 88% to 99% of a colloid matrix and 1% to 12% of a silicon-containing acrylate coupling agent in percentage by mass.

3. The photoresist for nanoimprinting process according to claim 1, characterized in that: The photoresist comprises 92% to 94% of a colloid matrix and 6% to 8% of a silicon-containing acrylate coupling agent in percentage by mass.

4. The photoresist for nanoimprinting process according to claim 1, characterized in that: The solvent includes any one or more of propylene glycol monomethyl ether, propylene glycol monobutyl ether, diethylene glycol dimethyl ether, diethylene glycol monomethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol monomethyl ether, propylene glycol methyl ether acetate, butyl acetate and butyl lactate.

5. The method for preparing a photoresist for nanoimprinting process according to any one of claims 1 to 4, characterized in that: The steps include: Mix the components in proportion.

6. Use of the photoresist for nanoimprint process according to any one of claims 1 to 4 in nanoimprinting.

7. The use according to claim 6, characterized in that: The nano-imprinting method comprises: coating the photoresist on the surface of the substrate after purification and then pre-baking, then imprinting a pattern and solidifying the pattern, and then stripping the film to obtain an imprinted photoresist pattern.

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