Resist composition and method for forming patterned film by plasma CVD method

Abstract

To provide a resist composition enabling formation of a film that allows easy removal without a stripping liquid and that exhibits thermal resistance adequate to endure high-temperature plasma CVD, a cured product of the resist composition, a patterned resist film composed of the cured product, and a pattern forming method by plasma CVD using the resist composition.SOLUTION: The resist composition comprises a silsesquioxane (A1) having a (meth)acryloyl group, a silsesquioxane (A2) having an oxetanyl group, a radical polymerization initiator (B1), a cationic polymerization initiator (B2), and a particulate filler (C).SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a resist composition, a cured product of the resist composition, a patterned resist film made of the cured product, and a method for forming a patterned film by a plasma CVD method using the resist composition. [Background technology]

[0002] Resist materials are used as protective materials when forming electrode circuits in semiconductors, plate making, printed circuit boards, etc. Resist materials are indispensable for the manufacture of electronic parts for home appliances, industrial use, automotive use, aviation, or space use, industrial robots, solar cells, etc.

[0003] Resist materials are typically patterned by methods such as printing, photolithography, etc. Patterned films made of resist materials are used as etching masks or molds for plating, CVD, etc. Generally, a patterned film formed using a resist material is often peeled off from a substrate using an alkaline developer or an organic solvent.

[0004] A method for obtaining a resist material that can be pattern-printed by a printing method such as screen printing includes, for example, imparting thixotropy to the resist material. Specifically, the resist material contains an inorganic thixotropic agent such as hydrophobic silica or clay for the purpose of imparting thixotropy.

[0005] However, films made of such resist materials are difficult to peel off from substrates. To peel off such films made of resist materials, a method has been proposed in which an alkaline stripping solution is sprayed onto the substrate to forcibly peel off the film made of resist material (Patent Document 1). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 3421333 Summary of the Invention [Problem to be solved by the invention]

[0007] However, when an alkaline stripping solution is sprayed onto a substrate, the substrate may be damaged depending on the material of the substrate. Also, for the purpose of shortening the time required for a processing process using a film made of a resist material, there is a demand for a resist material that can form a film that can be easily stripped from a substrate without using a stripping solution. Furthermore, in terms of compatibility with plasma CVD, the film made of the resist material is also required to have heat resistance that can withstand plasma CVD, which is performed at high temperatures.

[0008] The present invention has been made in view of the above-mentioned problems, and has an object to provide a resist composition that can be easily stripped without the use of a stripping solution and that can form a film that has heat resistance sufficient to withstand plasma CVD performed at high temperatures; a cured product of the resist composition; a patterned resist film made of the cured product; and a method of forming a pattern by plasma CVD that uses the resist composition. [Means for solving the problem]

[0009] The present inventors have discovered that the above-mentioned problems can be solved by incorporating into a resist composition a silsesquioxane (A1) having a (meth)acryloyl group, a silsesquioxane (A2) having an oxetanyl group, a radical polymerization initiator (B1), a cationic polymerization initiator (B2), and a particulate filler (C), and have thus completed the present invention.

[0010] More specifically, the present invention provides the following (1) to (10). (1) A composition comprising a silsesquioxane (A), a polymerization initiator (B), and a fine particle filler (C), The silsesquioxane (A) contains a silsesquioxane (A1) having a (meth)acryloyl group and a silsesquioxane (A2) having an oxetanyl group, A resist composition, wherein the polymerization initiator (B) comprises a radical polymerization initiator (B1) and a cationic polymerization initiator (B2). (2) The resist composition according to (1), wherein the ratio of the mass of the silsesquioxane (A1) to the total mass of the silsesquioxane (A1) and the mass of the silsesquioxane (A2) is 10 mass % or more and 90 mass % or less. (3) Silsesquioxane (A1) is a (meth)acryloyloxy group C bonded to a silicon atom 1-10 The silsesquioxane (A2) has an alkyl group, and the silsesquioxane (A2) has a 3-ethyloxetan-3-yl C 1-4 Alkyloxy C 1-10 The resist composition according to (1) or (2), which has an alkyl group. (4) The resist composition according to any one of (1) to (3), wherein the fine particle filler (C) comprises silica fine particles and / or acrylic resin fine particles. (5) The resist composition according to (4), wherein the particulate filler (C) contains silica fine particles, and the silica fine particles have been surface-treated with silicone oil or hexamethyldisilazane. (6) A cured product of the resist composition according to any one of (1) to (5). (7) A patterned resist film comprising the cured product according to (6). (8) Printing the resist composition according to any one of (1) to (5) onto a substrate to form a patterned resist composition film; curing the patterned resist composition film by exposure and / or heating to form a patterned resist film; forming a film on the surface of the substrate on which the resist film is formed by a plasma CVD method; peeling the patterned resist film from the substrate; A method for forming a patterned film by a plasma CVD method, comprising: (9) The substrate has a smooth main surface, printing a resist composition onto the smooth main surface; The method for forming a patterned film by a plasma CVD method according to (8), wherein the ratio of the mass of the silsesquioxane (A1) to the total mass of the silsesquioxane (A1) and the silsesquioxane (A2) is 45 mass% or more and 70 mass% or less. (10) The substrate has a main surface having projections and recesses, a resist composition is printed on the main surface having the irregularities; The method for forming a patterned film by a plasma CVD method according to (8), wherein the ratio of the mass of the silsesquioxane (A1) to the total mass of the silsesquioxane (A1) and the silsesquioxane (A2) is 45 mass% or more and 75 mass% or less. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a resist composition that can form a film that can be easily stripped without using a stripping solution and that has heat resistance sufficient to withstand plasma CVD performed at high temperatures; a cured product of the resist composition; a patterned resist film made of the cured product; and a method of forming a pattern by plasma CVD that uses the resist composition. DETAILED DESCRIPTION OF THE INVENTION

[0012] The present invention will be described in detail below.

[0013] <Resist composition> The resist composition includes a silsesquioxane (A), a polymerization initiator (B), and a particulate filler (C). The silsesquioxane (A) includes a silsesquioxane (A1) having a (meth)acryloyl group and a silsesquioxane (A2) having an oxetanyl group. The polymerization initiator (B) includes a radical polymerization initiator (B1) and a cationic polymerization initiator (B2). The resist composition may contain various components that have conventionally been added to various resist compositions, so long as the desired effect is not impaired.

[0014] By using the above resist composition, it is possible to form a resist film that can be easily stripped without using a stripping solution and has heat resistance that can withstand plasma CVD performed at high temperatures. As described above, the resist film formed using the resist composition can be easily stripped without using a stripping solution. Therefore, the use of the resist composition can reduce the cost of disposing of the used stripping solution and also reduce the environmental impact caused by disposing of a large amount of stripping solution and a large amount of rinse water generated when rinsing the substrate after stripping.

[0015] Essential and optional components that the resist composition may contain will be described below.

[0016] <Silsesquioxane (A)> The resist composition contains a silsesquioxane (A). The silsesquioxane (A) contains a silsesquioxane (A1) having a (meth)acryloyl group and a silsesquioxane (A2) having an oxetanyl group. The silsesquioxane (A) may contain, in addition to the silsesquioxane (A1) and the silsesquioxane (A2), another silsesquioxane (A3).

[0017] The ratio of the total mass of the silsesquioxane (A1) and the silsesquioxane (A2) to the mass of the silsesquioxane (A) is preferably 50% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, even more preferably 90% by mass or more, and particularly preferably 100% by mass.

[0018] The structure of the silsesquioxane (A) is not particularly limited, and the silsesquioxane (A) may be a cage silsesquioxane, a ladder silsesquioxane, an incomplete cage silsesquioxane, or a random silsesquioxane. The silsesquioxane (A) may contain two or more types selected from a cage silsesquioxane, a ladder silsesquioxane, an incomplete cage silsesquioxane, and a random silsesquioxane.

[0019] As the cage silsesquioxane, any of T8 silsesquioxane containing 8 silicon atoms, T10 silsesquioxane containing 10 silicon atoms, and T12 silsesquioxane containing 12 silicon atoms can be used.

[0020] [Silsesquioxane (A1)] The silsesquioxane (A1) is a silsesquioxane having a (meth)acryloyl group. The (meth)acryloyl group is usually bonded to a silicon atom in the silsesquioxane skeleton via a linking group having a valence of 2 or more. When the linking group is an n-valent group, n-1 (meth)acryloyl groups are bonded to one silicon atom via the linking group. Here, n is an integer of 2 or more, preferably an integer of 2 to 4, and more preferably 2 or 3.

[0021] The silsesquioxane (A1) is preferably composed of units represented by the following formula (1). The silsesquioxane (A1) may be composed of only one type of unit corresponding to the unit represented by formula (1), or may be composed of two or more types of units corresponding to the unit represented by formula (1). The silsesquioxane (A1) is preferably composed of only one type of unit corresponding to the unit represented by formula (1). CH=CHR 1 -CO-XR 2 -SiO 3 / 2 (1) In the above formula (1), R 1 is a hydrogen atom or a methyl group. 2is a hydrocarbon group having 1 to 10 carbon atoms. X is -O- or -NH-.

[0022] R 2 is a hydrocarbon group having 1 to 10 carbon atoms. 2 The hydrocarbon group as R may be an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a combination of an aliphatic hydrocarbon group and an aromatic hydrocarbon group. 2 The hydrocarbon group as is preferably an aliphatic hydrocarbon group.

[0023] R 2 The structure of the aliphatic hydrocarbon group as R may be a chain structure, a cyclic structure, or a combination of a chain structure and a cyclic structure, and is preferably a chain structure. 3 The chain aliphatic hydrocarbon group as may be a straight-chain aliphatic hydrocarbon group or a branched-chain aliphatic hydrocarbon group, and is preferably a straight-chain aliphatic hydrocarbon group.

[0024] R 2 The aliphatic hydrocarbon group as may be a saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group, and is preferably a saturated aliphatic hydrocarbon group. In other words, R 2 The hydrocarbon group as is preferably an alkylene group, and more preferably a straight-chain alkylene group.

[0025] Preferred specific examples of the straight-chain alkylene group include a methylene group, an ethane-1,2-diyl group (ethylene group), a propane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a heptane-1,7-diyl group, an octane-1,8-diyl group, a nonane-1,9-diyl group, and a decane-1,10-diyl group. Among these, ethane-1,2-diyl (ethylene), propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, and octane-1,8-diyl groups are preferred, and ethane-1,2-diyl (ethylene), propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, and hexane-1,6-diyl groups are more preferred.

[0026] In the above formula (1), X is —O— or —NH—, and is preferably —O—.

[0027] According to the above, the silsesquioxane (A1) is a (meth)acryloyloxy group bonded to a silicon atom. 1-10 (Meth)acryloylamino C bonded to an alkyl group or silicon atom 1-10 Preferably, the alkyl group is (meth)acryloyloxy C bonded to a silicon atom. 1-10 It is more preferred that it has an alkyl group.

[0028] As the constitutional unit represented by formula (1), units represented by the following formulae (1a) to (1j) are preferred, and units represented by the following formulae (1a) to (1e) are more preferred. CH=CHR 1 -CO-O-(CH2)2-SiO 3 / 2 (1a) CH=CHR 1 -CO-O-(CH2)3-SiO 3 / 2 (1b) CH=CHR 1 -CO-O-(CH2)4-SiO 3 / 2 (1c) CH=CHR1 -CO-O-(CH2)5-SiO 3 / 2 (1d) CH=CHR 1 -CO-O-(CH2)6-SiO 3 / 2 (1e) CH=CHR 1 -CO-NH-(CH2)2-SiO 3 / 2 (1f) CH=CHR 1 -CO-NH-(CH2)3-SiO 3 / 2 (1g) CH=CHR 1 -CO-NH-(CH2)4-SiO 3 / 2 ···(1h) CH=CHR 1 -CO-NH-(CH2)5-SiO 3 / 2 (1i) CH=CHR 1 -CO-NH-(CH2)6-SiO 3 / 2 ···(1j)

[0029] [Silsesquioxane (A2)] The silsesquioxane (A2) is a silsesquioxane having an oxetanyl group. The oxetanyl group is usually bonded to a silicon atom in the silsesquioxane skeleton via a linking group having a valence of 2 or more. When the linking group is an m-valent group, m-1 oxetanyl groups are bonded to one silicon atom via the linking group. Here, m is an integer of 2 or more, preferably an integer of 2 to 4, and more preferably 2 or 3.

[0030] The oxetanyl group of the silsesquioxane (A2) may have a substituent, which is preferably an alkyl group having 1 to 4 carbon atoms, more preferably an ethyl group.

[0031] The silsesquioxane (A2) is preferably composed of units represented by the following formula (2). The silsesquioxane (A2) may be composed of only one type of unit corresponding to the unit represented by formula (2), or may be composed of two or more types of units corresponding to the unit represented by formula (2). The silsesquioxane (A2) is preferably composed of only one type of unit corresponding to the unit represented by formula (2). OX-R 3 -OR 4 -SiO 3 / 2 (2) In the above formula (2), OX is a 3-ethyloxetan-3-yl group. 3 is an alkylene group having 1 to 4 carbon atoms. 4 is a hydrocarbon group having from 1 to 10 carbon atoms.

[0032] R 3 The alkylene group as R may be a linear alkyl group or a branched alkyl group, and is preferably a linear alkyl group. 3 Suitable examples of the alkylene group as include a methylene group, an ethane-1,2-diyl group (ethylene group), a propane-1,3-diyl group, and a butane-1,4-diyl group.

[0033] R 4 The hydrocarbon group having 1 to 10 carbon atoms as R in formula (1) 2 The same applies to hydrocarbon groups having 1 to 10 carbon atoms as above.

[0034] According to the above, the silsesquioxane (A2) is 3-ethyloxetan-3-yl C 1-4 Alkyloxy C 1-10 It preferably has an alkyl group.

[0035] As the constitutional unit represented by formula (2), units represented by the following formulae (2a) to (2e) are preferred. OX-CH2-O-(CH2)2-SiO 3 / 2 (2a) OX-CH2-O-(CH2)3-SiO 3 / 2(2b) OX-CH2-O-(CH2)4-SiO 3 / 2 (2c) OX-CH2-O-(CH2)5-SiO 3 / 2 (2d) OX-CH2-O-(CH2)6-SiO 3 / 2 (2e)

[0036] [Other silsesquioxanes (A3)] In addition to the silsesquioxane (A1) and the silsesquioxane (A2), the resist composition may contain another silsesquioxane (A3) that does not fall under the category of the silsesquioxane (A1) and the silsesquioxane (A2). The type of the other silsesquioxane (A3) is not particularly limited as long as the desired effect is not impaired.

[0037] Other silsesquioxanes (A3) include, for example, silsesquioxanes composed of units represented by the following formulae (3a) to (3g): In the following formulae, Ph is a phenyl group, Gly is a glycidyl group, and Chx is a 3,4-epoxycyclohexyl group. CH2=CH-SiO 3 / 2 (3a) Ph-SiO 3 / 2 (3b) HS-(CH2)3-SiO 3 / 2 (3c) Gly-O-(CH2)3-Si(CH3)2-O-SiO 3 / 2 (3d) Chx-(CH2)2-Si(CH3)2-O-SiO 3 / 2 (3e) CH2=CH-Si(CH3)2-O-SiO 3 / 2 (3f) HO-(CH2)3-Si(CH3)2-O-SiO 3 / 2 ···(3g)

[0038] In the resist composition, the ratio of the mass of the silsesquioxane (A1) to the total mass of the silsesquioxane (A1) and the silsesquioxane (A2) is preferably 10 mass% or more and 90 mass% or less, more preferably 20 mass% or more and 85 mass% or less, and even more preferably 30 mass% or more and 80 mass% or less.

[0039] When the resist composition is applied to a smooth main surface of a substrate having such a smooth main surface, the ratio of the mass of the silsesquioxane (A1) to the total mass of the silsesquioxane (A1) and the silsesquioxane (A2) is preferably 45 mass% or more and 70 mass% or less. Here, a smooth surface is, for example, a surface having a surface roughness Ra of 2 nm or less.

[0040] When the resist composition is applied to a main surface having irregularities on a substrate having the main surface, the ratio of the mass of the silsesquioxane (A1) to the total mass of the silsesquioxane (A1) and the silsesquioxane (A2) is preferably 45 mass% or more and 75 mass% or less. A preferred uneven structure is a structure in which a plurality of quadrangular pyramidal protrusions are regularly arranged adjacent to each other. The height of the protrusions (depth of the valleys between the protrusions) is, for example, about 0.5 μm to 10 μm, preferably 1 μm to 7 μm, and more preferably 1 μm to 5 μm.

[0041] <Polymerization initiator (B)> The resist composition contains a polymerization initiator (B) as a component that cures the silsesquioxane (A). The polymerization initiator (B) contains a combination of a radical polymerization initiator (B1) as a component that cures the silsesquioxane (A1) having a (meth)acryloyl group, and a cationic polymerization initiator (B2) as a component that cures the silsesquioxane (A2) having an oxetanyl group.

[0042] The polymerization initiator (B) may be a thermal polymerization initiator that promotes curing by heating, or a photopolymerization initiator that promotes curing by exposure to light. Either a thermal polymerization initiator or a photopolymerization initiator may be used as the polymerization initiator (B), and it is preferable to use a photopolymerization initiator.

[0043] [Radical polymerization initiator (B1)] As the radical polymerization initiator (B1), any known radical polymerization initiator can be used without any particular limitation.

[0044] Suitable examples of the radical polymerization initiator (B1) include benzophenone, methyl o-benzoylbenzoate, 4,4-bis(dimethylamine)benzophenone, 4,4-bis(diethylamine)benzophenone, α-aminoacetophenone, 4,4-dichlorobenzophenone, 4-benzoyl-4-methyldiphenyl ketone, dibenzyl ketone, fluorenone, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2-hydroxy-2-methylpropiophenone, p-tert -butyldichloroacetophenone, thioxanthone, 2-methylthioxanthone, 2-chlorothioxanthone, 2-isopropylthioxanthone, diethylthioxanthone, benzyl dimethyl ketal, benzyl methoxyethyl acetal, benzoin methyl ether, benzoin butyl ether, anthraquinone, 2-tert-butylanthraquinone, 2-amylanthraquinone, β-chloroanthraquinone, anthrone, benzanthrone, dibenzsuberone, methyleneanthrone, 4-azidobenzyl acetophenone, 2,6-bis(p-azidobenzylidene)cyclohexane, 2,6-bis(p-azidobenzylidene)-4-methylcyclohexanone, 2-phenyl-1,2-butadione-2-(o-methoxycarbonyl)oxime, 1-phenyl-propanedione-2-(o-ethoxycarbonyl)oxime, 1,3-diphenyl-propanetrione-2-(o-ethoxycarbonyl)oxime, 1-phenyl-3-ethoxy-propanetrione-2-(o-benzoyl)oxime, Michler's ketone, Examples include 2-methyl-1[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone, naphthalenesulfonyl chloride, quinolinesulfonyl chloride, n-phenylthioacridone, 4,4-azobisisobutyronitrile, diphenyl disulfide, benzthiazole disulfide, triphenylphosphine, camphorquinone, carbon tetrabromide, tribromophenyl sulfone, and benzoin peroxide.

[0045] These radical polymerization initiators (B1) may be used singly or in combination of two or more.

[0046] The amount of the radical polymerization initiator (B1) used is preferably 0.01 to 10 parts by mass, more preferably 0.05 to 5 parts by mass, and even more preferably 0.1 to 3 parts by mass, per 100 parts by mass of the silsesquioxane (A1).

[0047] [Cationic Polymerization Initiator (B2)] As the cationic polymerization initiator (B2), any known cationic polymerization initiator can be used without any particular limitation. As the cationic polymerization initiator (B2), onium salts such as iodonium salts, sulfonium salts, ammonium salts, and phosphonium salts are preferred. Among these, iodonium salts and sulfonium salts are preferred because of their ease of availability and handling.

[0048] Suitable examples of iodonium ions constituting iodonium salts include iodonium ions such as diphenyliodonium, di-p-tolyliodonium, bis(4-dodecylphenyl)iodonium, bis(4-methoxyphenyl)iodonium, (4-octyloxyphenyl)phenyliodonium, bis(4-decyloxy)phenyliodonium, 4-(2-hydroxytetradecyloxy)phenylphenyliodonium, 4-isopropyl-4′-methyldiphenyliodonium, 4-isobutylphenyl(p-tolyl)iodonium, and 2,4,6-trimethylphenyl(4-nitrophenyl)iodonium.

[0049] Suitable examples of sulfonium ions constituting the sulfonium salt include triphenylsulfonium, tri-p-tolylsulfonium, tri-o-tolylsulfonium, tris(4-methoxyphenyl)sulfonium, 1-naphthyldiphenylsulfonium, 2-naphthyldiphenylsulfonium, tris(4-fluorophenyl)sulfonium, tri-1-naphthylsulfonium, tri-2-naphthylsulfonium, tris(4-hydroxyphenyl)sulfonium, 4-(phenylthio)phenyldiphenylsulfonium, 4-(p-tolylthio)phenyldi-p-tolylsulfonium, 4-(4-methoxyphenylthio)phenylbis(4-methoxyphenyl)sulfonium, 4-(phenylthio)phenylbis(4-fluorophenyl)sulfonium, 4-(phenylthio)phenylbis(4-methoxyphenyl)sulfonium, 4-(phenylthio)phenyldi-p-tolylsulfonium, [4-(4-biphenylylthio)phenyl]-4-biphenylylphenylsulfonium, [4-(2-thio oxanthonylthio)phenyl]diphenylsulfonium, bis[4-(diphenylsulfonio)phenyl]sulfide, bis[4-{bis[4-(2-hydroxyethoxy)phenyl]sulfonio}phenyl]sulfide, bis{4-[bis(4-fluorophenyl)sulfonio]phenyl}sulfide, bis{4-[bis(4-methylphenyl)sulfonio]phenyl}sulfide, bis{4-[bis(4-methoxyphenyl)sulfonio]phenyl}sulfide, 4-(4-benzoyl-2-chloride 4-(4-benzoyl-2-chlorophenylthio)phenylbis(4-fluorophenyl)sulfonium, 4-(4-benzoyl-2-chlorophenylthio)phenyldiphenylsulfonium, 4-(4-benzoylphenylthio)phenylbis(4-fluorophenyl)sulfonium, 4-(4-benzoylphenylthio)phenyldiphenylsulfonium, 7-isopropyl-9-oxo-10-thia-9,10-dihydroanthracen-2-yldi-p-tolylsulfonium, 7-isopropyl-9-oxo-10-thia-9,10-dihydroanthracen-2-yldi-p-tolylsulfonium,10-Dihydroanthracen-2-yldiphenylsulfonium, 2-[(di-p-tolyl)sulfonio]thioxanthone, 2-[(diphenyl)sulfonio]thioxanthone, 4-(9-oxo-9H-thioxanthen-2-yl)thiophenyl-9-oxo-9H-thioxanthen-2-ylphenylsulfonium, 4-[4-(4-tert-butylbenzoyl)phenylthio]phenyldi-p-tolylsulfonium, 4-[4-(4-tert-butylbenzoyl)phenylthio]phenyl ]phenyldiphenylsulfonium, 4-[4-(benzoylphenylthio)]phenyldi-p-tolylsulfonium, 4-[4-(benzoylphenylthio)]phenyldiphenylsulfonium, 5-(4-methoxyphenyl)thiaanthrenenium, 5-phenylthiaanthrenenium, 5-tolylthiaanthrenenium, 5-(4-ethoxyphenyl)thiaanthrenenium, and triarylsulfonium such as 5-(2,4,6-trimethylphenyl)thiaanthrenenium.

[0050] The anions that constitute the onium salts include tetrakis(pentafluorophenyl)boron anion, tetrakis(3,4,5-trifluorophenyl)boron anion, tetrakis(4-nonafluorobiphenyl)boron anion, tetrakis(1-heptafluoronaphthyl)boron anion, tetrakis(2-nonaphenylbiphenyl)boron anion, tetrakis(2-heptafluoronaphthyl)boron anion, tetrakis(7-nonafluoroanthryl)boron anion, tetrakis(4'-(methoxy)octafluorobiphenyl)boron anion, tetrakis(2,4,6-tris(trifluoromethyl)phenyl)boron anion, tetrakis(3,5-bis(trifluoromethyl)phenyl)boron anion, tetrakis(2,3-bis(pentafluorophenyl)boron) Preferred are tetrakis(pentafluoroethyl)naphthyl)boron anion, tetrakis(2-isopropoxy-hexafluoronaphthyl)boron anion, tetrakis(9,10-bis(heptafluoropropyl)heptafluoroanthryl)boron anion, tetrakis(9-nonafluorophenanthryl)boron anion, tetrakis(4-[tri(isopropyl)silyl]-tetrafluorophenyl)boron anion, tetrakis(9,10-bis(p-tolyl)-heptafluorophenanthryl)boron anion, tetrakis(4-[dimethyl(t-butyl)silyl]-tetrafluorophenyl)boron anion, monophenyltris(pentafluorophenyl)boron anion, and monoperfluorobutyltris(pentafluorophenyl)boron anion.

[0051] These cationic polymerization initiators (B2) may be used singly or in combination of two or more.

[0052] The amount of the cationic polymerization initiator (B2) used is preferably 0.01 to 10 parts by mass, more preferably 0.05 to 5 parts by mass, and even more preferably 0.1 to 3 parts by mass, per 100 parts by mass of the silsesquioxane (A1).

[0053] <Fine particle filler (C)> The resist composition contains a fine particle filler (C) for the purposes of adjusting the viscosity of the resist composition, increasing the flexibility of the resist film formed using the resist composition, and suppressing warpage. The type of particulate filler (C) is not particularly limited as long as the desired effect is not impaired. The particulate filler (C) may be inorganic fine particles made of an inorganic material or resin fine particles made of an organic material such as a resin.

[0054] The particulate filler (C) preferably contains silica fine particles and / or acrylic resin fine particles, and more preferably is silica fine particles and / or acrylic resin fine particles.

[0055] From the viewpoint of the thixotropy of the resist composition, hydrophobic silica particles are preferred as the silica particles. Suitable hydrophobic silica particles include those whose surfaces have been treated with silicone oil or hexamethyldisilazane.

[0056] The particle size of the particulate filler (C) is not particularly limited as long as the desired effect is not impaired. The average particle size of the particulate filler (C) is preferably 5 nm or more and 50 μm or less in terms of the volume average particle size (D50) measured by a laser diffraction particle size distribution measuring device. The particle size of the particulate filler (C) is appropriately selected depending on the type of the particulate filler (C). For example, the volume average particle diameter (D50) of the silica fine particles is preferably 5 nm or more and 100 nm or less, and more preferably 10 nm or more and 30 nm or less. The volume average particle diameter (D50) of the acrylic resin fine particles is preferably 5 μm or more and 50 μm or less.

[0057] The amount of the fine particle filler (C) used is preferably 1 part by mass or more and 30 parts by mass or less, and more preferably 5 parts by mass or more and 20 parts by mass or less, per 100 parts by mass of the silsesquioxane (A).

[0058] <Other ingredients> The resist composition may contain components other than the above-mentioned silsesquioxane (A), polymerization initiator (B), and fine particle filler (C), as long as the desired effects are not impaired. Examples of other components include surfactants, antioxidants, resins, thermal polymerization inhibitors, antifoaming agents, silane coupling agents, dyes, pigments, etc. The amounts of these components used are determined appropriately taking into consideration the amounts of these components conventionally blended in resist compositions.

[0059] <Method of manufacturing resist composition> A resist composition can be produced by mixing the desired amounts of each of the components described above. There are no particular limitations on the equipment used for mixing, as long as it can uniformly mix and disperse the components contained in the resist composition.

[0060] The resist composition described above is printed on a desired substrate and then cured by exposure and / or heating to form a cured product. In this case, a patterned film made of the resist composition is formed by printing, and then the patterned film is cured to obtain a patterned resist film made of the cured product of the resist composition.

[0061] <Method for forming a patterned film using plasma CVD> printing the resist composition on a substrate to form a patterned resist composition film; curing the patterned resist composition film by exposure and / or heating to form a patterned resist film; forming a film on the surface of the substrate on which the resist film is formed by a plasma CVD method; Stripping the patterned resist film from the substrate; By the method including the above, a patterned film can be formed by plasma CVD.

[0062] An example of a method for printing the resist composition onto a substrate is screen printing, which makes it possible to easily form a resist composition film patterned into a desired shape.

[0063] The substrate is not particularly limited as long as the desired effect is not impaired. The surface of the substrate may be smooth or may have irregularities. When the surface of the substrate is irregular, the irregularities may be regular or irregular. A preferred uneven structure is a structure in which a plurality of quadrangular pyramidal protrusions are regularly arranged so that the protrusions are adjacent to each other.

[0064] The material of the substrate is not particularly limited as long as it does not soften, melt, decompose, or chemically degrade under the high temperatures encountered during plasma CVD. Typical substrate materials include silicon, silicon carbide, gallium nitride, germanium, gallium arsenide, and glass.

[0065] The exposure conditions or heating conditions for curing the patterned resist composition film are not particularly limited as long as the curing of the resist composition proceeds satisfactorily. The exposure conditions or heating conditions are appropriately determined taking into consideration, for example, the type and amount of polymerization initiator (B) used.

[0066] Next, a film is formed by plasma CVD on the surface of the substrate on which the patterned resist film has been formed. In this case, the patterned resist film is used as a template for forming a patterned film by plasma CVD. As a result, the film formed by plasma CVD fills in areas on the substrate where no resist film is present, and the film formed by plasma CVD is deposited on the resist film. The film deposited on the resist film is peeled off from the substrate together with the resist film in a subsequent step.

[0067] When performing plasma CVD, the resist film is typically exposed to a high temperature of 150°C or higher and 250°C or lower for a period of 5 seconds to 10 minutes. However, the resist film formed using the resist composition exhibits sufficiently high heat resistance, making it difficult to peel off from the substrate under the temperature conditions required for plasma CVD. This allows for successful formation of a patterned film by plasma CVD using the patterned resist film as a mold.

[0068] The material of the film formed by plasma CVD includes hydrogenated amorphous silicon.

[0069] After plasma CVD is completed, the patterned resist film is stripped from the substrate, thereby obtaining a substrate provided with a patterned film formed by plasma CVD. The patterned resist film is usually removed after the substrate has been cooled, preferably to a temperature of about 15°C or higher and 30°C or lower.

[0070] The patterned resist film may be peeled off from the substrate naturally as the substrate cools, or may be peeled off from the substrate by blowing a gas such as air or nitrogen onto the resist film, or may be peeled off by applying an adhesive tape onto the resist film. [Example]

[0071] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples.

[0072] In the examples and comparative examples, the following A1-1 and A1-2 were used as the silsesquioxane (A1). A1-1: CH2=CH―CO-O-(CH2)3-SiO 3 / 2 Silsesquioxane (AC-SQ TA-100, manufactured by Toagosei Co., Ltd.) consisting of units represented by the formula: A1-2:CH2=CCH3―CO-O-(CH2)3-SiO 3 / 2Silsesquioxane (MAC-SQ TM-100, manufactured by Toagosei Co., Ltd.) consisting of units represented by the formula:

[0073] In the examples and comparative examples, the following A2-1 was used as the silsesquioxane (A2). A2-1:OX-CH2-O-(CH2)3-SiO 3 / 2 Silsesquioxane (OX-SQ TX-100, manufactured by Toagosei Co., Ltd.) consisting of a unit represented by the formula: In the above formula, OX is a 3-ethyloxetan-3-yl group.

[0074] In the examples and comparative examples, the following B1 was used as the radical polymerization initiator (B1). B1: 2-hydroxy-2-methylpropiophenone In the examples and comparative examples, the following B2 was used as the cationic polymerization initiator (B2). B2: 4-Isopropyl-4'-methyldiphenyliodonium tetrakis(pentafluorophenyl)borate

[0075] In the examples and comparative examples, the following C1 was used as the fine particle filler (C). C1: Hydrophobic silica microparticles surface-treated with silicone oil (AEROSIL (registered trademark) RY200S (manufactured by Nippon Aerosil Co., Ltd.), average particle size (D50): 15 nm) C2: Acrylic resin microparticles (SE-006T (manufactured by Negami Chemical Industrial Co., Ltd.), average particle size (D50): 6 μm)

[0076] [Examples 1 to 4 and Comparative Examples 1 to 4] The type and amount of silsesquioxane (A) shown in Table 1, the type and amount of polymerization initiator (B) shown in Table 1, and the type and amount of fine particle filler (C) shown in Table 1 were uniformly mixed to obtain resist compositions of Examples 1 to 4 and Comparative Examples 1 to 4.

[0077] The resulting resist composition was used to form a resist film on a silicon substrate, and the formed resist film was then heated to 220° C., and the substrate was then rapidly cooled from 220° C. to room temperature. 220° C. is a temperature condition equivalent to plasma CVD.

[0078] Specifically, the resist composition was screen-printed onto the smooth surface of a silicon substrate so as to form a resist film with a thickness of 100 μm. The formed film made of the resist composition was exposed for 5 minutes at a high setting using an exposure device manufactured by DYMAX Corp. After exposure, the state of peeling of the formed resist film from the substrate was visually observed. Next, the substrate with the resist film was heated to 220°C over about 10 seconds and held at that temperature for 1 minute, after which the peeling state of the resist film from the substrate was visually observed. After visually observing the resist film, the substrate was rapidly cooled to a temperature close to room temperature to promote peeling of the resist film from the substrate. After cooling the substrate, the peeling state of the resist film from the substrate was visually observed. Table 1 shows the peeling state of the resist film from the substrate after exposure, after heating to 220°C, and after the substrate was rapidly cooled from 220°C. After exposure and heating at 220° C., the peeling state of the resist film from the substrate is as follows, as shown in Table 1. Note that A to C are good observation results. A: The resist film is not lifted from the substrate at all and is not peeled off from the substrate at all. B: Slight lifting of the resist film from the substrate was observed, but the resist film was not peeled off from the substrate. C: Some lifting of the resist film from the substrate is observed, but the resist film is only slightly peeled off from the substrate or not peeled off at all. D: The resist film is not completely peeled off from the substrate, but almost the entire resist film is peeled off or floating off from the substrate. E: The resist film is completely peeled off from the substrate.

[0079] After the substrate was rapidly cooled from 220° C., the peeling state of the resist film from the substrate was as follows, as shown in Table 1. Note that A to C are good observation results. A: The resist film is completely peeled off from the substrate. B: The resist film is not completely peeled off from the substrate, but almost the entire resist film is peeled off or floating off from the substrate. C: Some lifting of the resist film from the substrate is observed, but the resist film is only slightly peeled off from the substrate or not peeled off at all. D: Slight lifting of the resist film from the substrate was observed, but the resist film was not peeled off from the substrate. E: The resist film is not lifted from the substrate at all and is not peeled off from the substrate at all.

[0080] [Table 1]

[0081] Table 1 shows that the resist film formed using the resist composition of the example containing A1-1, which corresponds to silsesquioxane (A1) having a (meth)acryloyl group, A2-1, which corresponds to silsesquioxane (A2) having an oxetanyl group, B1, which is a radical polymerization initiator (B1), B2, which is a cationic polymerization initiator (B2), and particulate filler (C) did not peel excessively after exposure or heating at 220°C, and peeled well from the substrate when cooled after heating at 220°C.

[0082] On the other hand, the resist film formed using the comparative resist composition containing only either the silsesquioxane (A1) or the silsesquioxane (A2) peeled excessively from the substrate after exposure or when heated at 220°C, or did not peel sufficiently from the substrate when cooled after heating at 220°C.

[0083] [Examples 5 to 12 and Comparative Examples 5 to 14] Resist compositions of Examples 5 to 12 and Comparative Examples 5 to 14 were prepared and evaluated in the same manner as in Examples 1 to 4 and Comparative Examples 1 to 4, except that the silicon substrate was changed to a silicon substrate having a textured structure in which square pyramids with a height of approximately 5 μm were regularly arranged adjacent to one another on one main surface, and that the resist composition was screen-printed onto the textured main surface of the silicon substrate. Specifically, the peeling state of the resist film formed using the resulting resist composition from the substrate was evaluated in the same manner as in Examples 1 to 4 and Comparative Examples 1 to 4. The evaluation results are shown in Table 2.

[0084] [Table 2]

[0085] Table 2 shows that the resist film formed using the resist composition of the example containing A1-1, which corresponds to silsesquioxane (A1) having a (meth)acryloyl group, A2-1, which corresponds to silsesquioxane (A2) having an oxetanyl group, B1, which is a radical polymerization initiator (B1), B2, which is a cationic polymerization initiator (B2), and particulate filler (C) did not peel excessively after exposure or heating at 220°C, and peeled well from the substrate when cooled after heating at 220°C.

[0086] On the other hand, the resist film formed using the comparative resist composition containing only either the silsesquioxane (A1) or the silsesquioxane (A2) peeled excessively from the substrate after exposure or when heated at 220°C, or did not peel sufficiently from the substrate when cooled after heating at 220°C.

Claims

1. A composition comprising a silsesquioxane (A), a polymerization initiator (B), and a fine particle filler (C), The silsesquioxane (A) contains a silsesquioxane (A1) having a (meth)acryloyl group and a silsesquioxane (A2) having an oxetanyl group, A resist composition, wherein the polymerization initiator (B) comprises a radical polymerization initiator (B1) and a cationic polymerization initiator (B2).

2. 2. The resist composition according to claim 1, wherein a ratio of the mass of the silsesquioxane (A1) to the total mass of the silsesquioxane (A1) and the silsesquioxane (A2) is 10 mass% or more and 90 mass% or less.

3. The silsesquioxane (A1) is a (meth)acryloyloxy group bonded to a silicon atom. １－１０ The silsesquioxane (A2) has a 3-ethyloxetan-3-yl C １－４ Alkyloxy C １－１０ The resist composition according to claim 1 or 2, which has an alkyl group.

4. 3. The resist composition according to claim 1, wherein the fine particle filler (C) comprises silica fine particles and / or acrylic resin fine particles.

5. 5. The resist composition according to claim 4, wherein the particulate filler (C) contains silica fine particles, and the silica fine particles have been surface-treated with silicone oil or hexamethyldisilazane.

6. A cured product of the resist composition according to claim 1 or 2.

7. A patterned resist film comprising the cured product according to claim 6 .

8. Printing the resist composition according to claim 1 or 2 onto a substrate to form a patterned resist composition film; curing the patterned resist composition film by exposure and / or heating to form a patterned resist film; forming a film on the surface of the substrate on which the resist film is formed by a plasma CVD method; peeling the patterned resist film from the substrate; A method for forming a patterned film by a plasma CVD method, comprising:

9. the substrate has a smooth major surface; The resist composition is printed on the smooth main surface, 9. The method for forming a patterned film by a plasma CVD method according to claim 8, wherein the ratio of the mass of the silsesquioxane (A1) to the total mass of the silsesquioxane (A1) and the silsesquioxane (A2) is 45 mass% or more and 70 mass% or less.

10. the substrate has a main surface having projections and recesses; the resist composition is printed on the main surface having the irregularities; 9. The method for forming a patterned film by a plasma CVD method according to claim 8, wherein the ratio of the mass of the silsesquioxane (A1) to the total mass of the silsesquioxane (A1) and the silsesquioxane (A2) is 45 mass% or more and 75 mass% or less.

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