Resist material and pattern forming method

Abstract

The invention provides a resist material and a pattern forming method. [Problem] To provide a resist material having high sensitivity and improved LWR and CDU, and a pattern forming method using the same. [Solution] A resist material which contains a base polymer that contains a repeating unit (a) that is formed from a substituted or unsubstituted aryl sulfonic acid anion that is bonded to a polymer main chain having a group that contains an iodine atom or a bromine atom and an onium cation.

Description

Technical Field

[0001] The present invention relates to a resist material and a pattern forming method. Background Art

[0002] With the high integration and high speed of LSI, the pattern rules are being miniaturized rapidly. This is because: 5G high-speed communication and artificial intelligence (AI) are becoming more and more popular, and high-performance equipment is needed to process them. As the most advanced miniaturization technology, extreme ultraviolet (EUV) lithography with a wavelength of 13.5nm is used to mass-produce 5nm node equipment. Furthermore, research is being conducted on the use of EUV lithography in the next generation of 3nm node equipment and the next generation of 2nm node equipment. IMEC in Belgium has already clarified the development of 1nm and 0.7nm equipment.

[0003] While miniaturization is being carried out, image blurring caused by acid diffusion becomes a problem. In order to ensure the resolution in fine patterns with a size of less than 45nm, it is proposed that it is not only important to improve the dissolution contrast as previously proposed, but also to control the acid diffusion (Non-Patent Document 1). However, chemically amplified resist materials improve sensitivity and contrast by acid diffusion. Therefore, if you want to reduce the post-exposure baking (PEB) temperature or shorten the time to suppress the acid diffusion to the limit, the sensitivity and contrast will be significantly reduced.

[0004] Sensitivity, resolution, and edge roughness (LWR) show a triangular trade-off relationship. In order to improve the resolution, it is necessary to suppress the diffusion of acid, but when the acid diffusion distance becomes shorter, the sensitivity decreases.

[0005] It is effective to add an acid generator that generates a large volume of acid to inhibit acid diffusion. Therefore, it is proposed that the polymer contains a repeating unit derived from an onium salt having a polymerizable unsaturated bond. In this case, the polymer also functions as an acid generator (polymer-bonded acid generator). Patent document 1 proposes a sulfonium salt obtained by directly bonding a sulfonic acid to a main chain.

[0006] A resist material containing a polymer having an onium salt structure having an iodine atom or a bromine atom in the linking group portion between the polymer main chain and fluorosulfonic acid has been proposed (Patent Documents 2 and 3). Iodine atoms have high absorption for EUV light, and bromine atoms are ionized by EUV irradiation, and both of them have improved sensitivity and physical contrast.

[0007] The mechanism of acid generation under high-energy rays represented by EB and EUV light is advocated (non-patent document 2). Therefore, in EB and EUV exposure, the polymer is ionized to generate secondary electrons and diffuse, which transfer energy to the acid generator to generate acid. According to the results of the resist pattern transfer and simulation, it can be estimated that the distance from the light absorption point to the point where the acid is generated is 2.4nm (non-patent document 3). This distance includes the diffusion distance of the secondary electrons. It is recorded in this document that when the PEB temperature is changed, the total of the acid diffusion distance and the diffusion distance from the light absorption point to the point where the acid is generated is 4 to 8nm. Therefore, when the acid diffusion is suppressed in the application of low-temperature PEB, anionic bonded PAG polymers, etc., half of the diffusion distance is occupied by the diffusion from the light absorption point to the point where the acid is generated. In other words, it can be said that for miniaturization, it is not only important to control the acid diffusion, but also it is important to control the diffusion from the light absorption point to the point where the acid is generated, that is, the diffusion of secondary electrons.

[0008] Perfluoroalkyl compounds (PFAS) have been pointed out to have health effects, and there is a trend that European REACH will impose restrictions on the manufacture and sale of PFAS. Due to semiconductor lithography, a large number of compounds containing PFAS are currently used. For example, materials containing structures containing PFAS are used in surfactants, acid generators, etc.

[0009] Prior art literature

[0010] Patent Literature

[0011] Patent Document 1: Japanese Patent Application Publication No. 2006-178317

[0012] Patent Document 2: Japanese Patent Application Publication No. 2018-197853

[0013] Patent Document 3: Japanese Patent Application Publication No. 2019-008280

[0014] Non-patent literature

[0015] Non-patent document 1: SPIE Vol.6520 65203L-1 (2007)

[0016] Non-patent document 2: SPIE Vol. 5753 361 (2005)

[0017] Non-patent document 3: SPIE Vol.7969 796904-1 (2011) Summary of the invention

[0018] Problem that the invention aims to solve

[0019] For resist materials, it is desirable to develop an acid generator that can improve the LWR of line patterns, the size uniformity (CDU) of hole patterns, and also improve sensitivity. To this end, it is necessary to have high decomposition efficiency during exposure, inhibit acid diffusion, and have high affinity with alkaline developer.

[0020] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a resist material having high sensitivity and improved LWR and CDU, particularly among positive resist materials, and a pattern forming method using the same.

[0021] Solutions for solving problems

[0022] The inventors of the present invention have repeatedly conducted in-depth studies to achieve the above-mentioned purpose. As a result, it is believed that by using a base polymer containing a repeating unit a, the acid generator is directly excited by the absorption of iodine atoms or bromine atoms during exposure and generates acid, wherein the repeating unit a is formed by a substituted or unsubstituted aryl sulfonic acid anion and an onium cation, and the substituted or unsubstituted aryl sulfonic acid anion is bonded to a polymer main chain having a group containing an iodine atom or a bromine atom. In the case of a direct excitation mechanism, it is not affected by the diffusion of secondary electrons, so the diffusion becomes lower. It is further found that due to the low acid diffusivity caused by the sulfonic acid bonded to the polymer main chain generated by exposure, or the decomposition efficiency achieved by direct excitation based on exposure by absorption and ionization of iodine atoms or bromine atoms, the acid diffusion can be suppressed at the same time, and the affinity with the alkaline developer is high, so that high sensitivity, low acid diffusion, high contrast and low swelling characteristics can be obtained, thereby, LWR and CDU can be improved, high sensitivity, excellent resolution, and a wide process margin resist material can be obtained, thereby completing the present invention.

[0023] That is, the present invention provides the following resist material and pattern forming method.

[0024] 1. A resist material comprising a base polymer containing a repeating unit a, wherein the repeating unit a is formed of a substituted or unsubstituted arylsulfonic acid anion and an onium cation, wherein the substituted or unsubstituted arylsulfonic acid anion is bonded to a polymer main chain having a group containing an iodine atom or a bromine atom.

[0025] 2. The resist material according to 1, wherein the repeating unit a is represented by the following formula (a1) or (a2).

[0026]

[0027] (Wherein, m is an integer from 0 to 5.

[0028] R A A hydrogen atom or a methyl group.

[0029] R Bis a hydrogen atom or optionally with X 1 bonded to form a ring.

[0030] X 1 It is a single bond, a phenylene group, a naphthalene ring, an ester bond or an amide bond.

[0031] X 2A It is a divalent organic group having 1 to 24 carbon atoms and having at least one iodine atom or bromine atom, and optionally has at least one selected from the group consisting of an oxygen atom, a nitrogen atom and a sulfur atom.

[0032] X 2B It is a monovalent organic group having 1 to 10 carbon atoms and having at least one iodine atom or bromine atom, and may have at least one selected from the group consisting of an oxygen atom, a nitrogen atom and a sulfur atom.

[0033] X 3 It is a single bond, an ether bond, an ester bond, a thioether bond or an alkanediyl group having 1 to 6 carbon atoms.

[0034] X 4 It is a trivalent organic group having 1 to 12 carbon atoms, and may have at least one selected from an oxygen atom, a nitrogen atom and a sulfur atom.

[0035] The group R is an (m+2)-valent aromatic hydrocarbon group having 6 to 10 carbon atoms.

[0036] R 1 It is a saturated hydrocarbon group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a fluorine atom, a trifluoromethoxy group, a difluoromethoxy group, a cyano group or a nitro group.

[0037] M + is a sulfonium cation or an iodonium cation. )

[0038] 3. The resist material according to 1 or 2, wherein the base polymer further comprises a repeating unit represented by the following formula (b1) or a repeating unit represented by the following formula (b2).

[0039]

[0040] (Where R A Each is independently a hydrogen atom or a methyl group.

[0041] Y 1 It is a single bond, a linking group having 1 to 12 carbon atoms and containing at least one selected from the group consisting of a phenylene group or a naphthylene group, or an ester bond, an ether bond, a lactone ring, a hydroxyl group, and a halogen atom.

[0042] Y 2 It is a single bond or an ester bond.

[0043] Y 3 It is a single bond, an ether bond or an ester bond.

[0044] R 11 and R 12 Each is independently an acid-labile group.

[0045] R 13 It is a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a trifluoromethyl group, a cyano group, a saturated hydrocarbon group having 1 to 6 carbon atoms, a saturated hydrocarbonoxy group having 1 to 6 carbon atoms, a saturated hydrocarboncarbonyl group having 2 to 7 carbon atoms, a saturated hydrocarboncarbonyloxy group having 2 to 7 carbon atoms, or a saturated hydrocarbonoxycarbonyl group having 2 to 7 carbon atoms.

[0046] R 14 It is a single bond or an alkanediyl group having 1 to 6 carbon atoms, and a part of -CH2- in the alkanediyl group may be replaced by an ether bond or an ester bond.

[0047] a is 1 or 2. b is an integer from 0 to 4. Wherein, 1≤a+b≤5. )

[0048] 4. The resist material according to 3, which is a chemically amplified positive resist material.

[0049] 5. The resist material according to any one of 1 to 4, further comprising an organic solvent.

[0050] 6. The anti-corrosion material according to any one of 1 to 5, further comprising a surfactant.

[0051] 7. A pattern forming method, comprising: a step of forming a resist film on a substrate using the resist material of any one of 1 to 6; a step of exposing the resist film to high-energy rays; and a step of developing the exposed resist film using a developer.

[0052] 8. The pattern forming method according to 7, wherein the high-energy radiation is KrF excimer laser, ArF excimer laser, electron beam (EB) or EUV having a wavelength of 3 to 15 nm.

[0053] Effects of the Invention

[0054] The sensitivity and contrast of the resist material containing a base polymer containing a repeating unit a composed of a substituted or unsubstituted arylsulfonic acid anion and an onium cation bonded to a polymer main chain having a group containing an iodine atom or a bromine atom are improved by the iodine atom or the bromine atom. The arylsulfonic acid anion is bonded to the polymer main chain, so the acid diffusion distance is short, and the alkali dissolution rate is improved due to the generation of a carboxyl group. Thus, a resist material with improved LWR and CDU can be constructed. DETAILED DESCRIPTION

[0055] [Resist material]

[0056] The anti-corrosion material of the present invention comprises a base polymer containing a repeating unit a, wherein the repeating unit a is formed of a substituted or unsubstituted arylsulfonic acid anion and an onium cation, wherein the substituted or unsubstituted arylsulfonic acid anion is bonded to a polymer main chain having a group containing an iodine atom or a bromine atom. The repeating unit a functions as an acid generator, and therefore the base polymer is a polymer-bonded acid generator.

[0057] [Base polymer]

[0058] The repeating unit a is preferably a repeating unit represented by the following formula (a1) (hereinafter also referred to as repeating unit a1) or a repeating unit represented by the following formula (a2) (hereinafter also referred to as repeating unit a2).

[0059]

[0060] In the formulas (a1) and (a2), m is an integer of 0-5.

[0061] In formula (a1) and (a2), R A is a hydrogen atom or a methyl group. B is a hydrogen atom or optionally with X 1 bonded to form a ring.

[0062] In formula (a1) and (a2), X 1 It is a single bond, a phenylene group, a naphthalene ring, an ester bond or an amide bond.

[0063] In formula (a1), X 2A It is a divalent organic group having 1 to 24 carbon atoms and having at least one iodine atom or bromine atom, and optionally has at least one selected from the group consisting of an oxygen atom, a nitrogen atom and a sulfur atom.

[0064] X 2AThe divalent organic group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include alkylene groups having 1 to 24 carbon atoms in which a part or all of the hydrogen atoms are replaced by iodine atoms or bromine atoms. Examples of the alkylene group having 1 to 24 carbon atoms include alkanediyl groups such as methanediyl, ethane-1,1-diyl, ethane-1,2-diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, decane-1,10-diyl, undecane-1,11-diyl, dodecane-1,12-diyl, tridecane-1,13-diyl, tetradecane-1,14-diyl, pentadecane-1,15-diyl, hexadecane-1,16-diyl, heptadecane-1,17-diyl, octadecane-1,18-diyl, nonadecane-1,19-diyl and eicosane-1,20-diyl; and cyclopentanediyl groups such as cyclopentane-1,1-diyl, cyclopentane-1,1-diyl, cyclopentane-1,1-diyl, cyclopentane-1,1-diyl, cyclopentane-1,1-diyl, cyclopentane-1,1-diyl, cyclopentane-1,1-diyl, cyclopentane-1,1-diyl, cyclopentane-1,1 cyclopentanediyl, methylcyclopentanediyl, dimethylcyclopentanediyl, trimethylcyclopentanediyl, tetramethylcyclopentanediyl, cyclohexanediyl, methylcyclohexanediyl, dimethylcyclohexanediyl, trimethylcyclohexanediyl, tetramethylcyclohexanediyl, norbornanediyl, adamantanediyl and the like; arylene groups such as phenylene, methylphenylene, ethylphenylene, n-propylphenylene, isopropylphenylene, n-butylphenylene, isobutylphenylene, sec-butylphenylene, tert-butylphenylene, naphthylene, methylnaphthylene, ethylnaphthylene, n-propylnaphthylene, isopropylnaphthylene, n-butylnaphthylene, isobutylnaphthylene, sec-butylnaphthylene, tert-butylnaphthylene, biphenyldiyl, methylbiphenyldiyl, dimethylbiphenyldiyl and the like; and groups obtained by combining these. In addition, X 2A Some or all of the hydrogen atoms in X are optionally substituted by a group containing at least one selected from an oxygen atom, a nitrogen atom and a sulfur atom, 2A A portion of -CH2- is optionally substituted by a group containing at least one selected from an oxygen atom, a nitrogen atom and a sulfur atom, and as a result, optionally contains a hydroxyl group, an ester bond, an ether bond, an amide bond, a urethane bond, a urea bond or the like.

[0065] In formula (a2), X 2B It is a monovalent organic group having 1 to 10 carbon atoms and having at least one iodine atom or bromine atom, and may have at least one selected from the group consisting of an oxygen atom, a nitrogen atom and a sulfur atom.

[0066] X 2BThe monovalent organic group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include hydrocarbon groups having 1 to 10 carbon atoms in which a part or all of the hydrogen atoms are replaced by iodine atoms or bromine atoms. Examples of the hydrocarbon group having 1 to 10 carbon atoms include alkyl groups having 1 to 10 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, 3-pentyl, tert-pentyl, neopentyl, n-hexyl, n-octyl, n-nonyl, and n-decyl; cyclic saturated hydrocarbon groups having 3 to 10 carbon atoms such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, adamantyl, norbornyl, cyclopropylmethyl, cyclopropylethyl, cyclobutylmethyl, cyclobutylethyl, cyclopentylmethyl, cyclopentylethyl, cyclohexylmethyl, cyclohexylethyl, methylcyclopropyl, methylcyclobutyl, methylcyclopentyl, methylcyclohexyl, ethylcyclopropyl, ethylcyclobutyl, ethylcyclopentyl, and ethylcyclohexyl; and vinyl, 1-propenyl, 2-propenyl, 10 alkenyl groups having 2 to 10 carbon atoms, such as thienyl, propynyl, butynyl, pentynyl, hexynyl, heptynyl, octynyl, nonynyl, and decenyl; alkynyl groups having 2 to 10 carbon atoms, such as ethynyl, propynyl, butynyl, pentynyl, hexynyl, heptynyl, octynyl, nonynyl, and decynyl; cyclic unsaturated aliphatic hydrocarbon groups having 3 to 10 carbon atoms, such as cyclopentenyl, cyclohexenyl, methylcyclopentenyl, methylcyclohexenyl, ethylcyclopentenyl, ethylcyclohexenyl, and norbornenyl; aryl groups having 6 to 10 carbon atoms, such as phenyl, methylphenyl, ethylphenyl, n-propylphenyl, isopropylphenyl, n-butylphenyl, isobutylphenyl, sec-butylphenyl, tert-butylphenyl, and naphthyl; aralkyl groups having 7 to 10 carbon atoms, such as benzyl, phenethyl, phenylpropyl, and phenylbutyl; and groups obtained by combining these. In addition, X 2B Some or all of the hydrogen atoms in X are optionally substituted by a group containing at least one selected from an oxygen atom, a nitrogen atom and a sulfur atom, 2B A portion of -CH2- is optionally substituted by a group containing at least one selected from an oxygen atom, a nitrogen atom and a sulfur atom, and as a result, optionally contains a hydroxyl group, an ester bond, an ether bond, an amide bond, a urethane bond, a urea bond or the like.

[0067] In formula (a1) and (a2), X 3 It is a single bond, an ether bond, an ester bond, a thioether bond or an alkanediyl group having 1 to 6 carbon atoms.

[0068] In formula (a2), X 4 X is a trivalent organic group having 1 to 12 carbon atoms, and may have at least one selected from an oxygen atom, a nitrogen atom and a sulfur atom. 4The trivalent organic group shown may be saturated or unsaturated, and may be any of linear, branched, and cyclic. As a specific example, a group obtained by further removing one hydrogen atom from an alkylene group having 1 to 12 carbon atoms may be listed. As the aforementioned alkylene group having 1 to 12 carbon atoms, an alkylene group having 1 to 12 carbon atoms among the aforementioned alkylene groups having 1 to 24 carbon atoms may be listed. In addition, X 4 Some or all of the hydrogen atoms in X are optionally substituted by a group containing at least one selected from an oxygen atom, a nitrogen atom and a sulfur atom, 4 A portion of -CH2- is optionally substituted by a group containing at least one selected from an oxygen atom, a nitrogen atom and a sulfur atom, and as a result, optionally contains a hydroxyl group, an ester bond, an ether bond, an amide bond, a urethane bond, a urea bond or the like.

[0069] In formulae (a1) and (a2), R is an (m+2)-valent aromatic hydrocarbon group having 6 to 10 carbon atoms. Specific examples of the (m+2)-valent aromatic hydrocarbon group include groups obtained by removing (m+2) hydrogen atoms from aromatic hydrocarbons such as benzene and naphthalene.

[0070] In formula (a1) and (a2), R 1 It is a saturated hydrocarbon group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a fluorine atom, a trifluoromethoxy group, a difluoromethoxy group, a cyano group or a nitro group.

[0071] Specific examples of anions of the repeating unit a include the following, but are not limited to these. BI is an iodine atom or a bromine atom.

[0072]

[0073]

[0074]

[0075]

[0076]

[0077]

[0078]

[0079]

[0080]

[0081]

[0082]

[0083]

[0084]

[0085]

[0086]

[0087]

[0088] In formulas (a1) and (a2), M + It is a sulfonium cation or an iodonium cation. The sulfonium cation is preferably a sulfonium cation represented by the following formula (M-1), and the iodonium cation is preferably an iodonium cation represented by the following formula (M-2).

[0089]

[0090] In formula (M-1) and (M-2), R 2 ~R 6 Each is independently a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom.

[0091] As R 2 ~R 6 Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

[0092] R 2 ~R 6The hydrocarbon group having 1 to 20 carbon atoms shown in the figure may be saturated or unsaturated, and may be any of straight chain, branched chain, and cyclic. Specific examples thereof include alkyl groups having 1 to 20 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, n-hexyl, n-octyl, n-nonyl, n-decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, heptadecyl, octadecyl, nonadecyl, and eicosyl; cyclic saturated hydrocarbon groups having 3 to 20 carbon atoms, such as cyclopropyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norbornyl, and adamantyl; and saturated hydrocarbon groups having 2 to 20 carbon atoms, such as vinyl, propenyl, butenyl, and hexenyl. alkenyl; alkynyl having 2 to 20 carbon atoms such as ethynyl, propynyl and butynyl; cyclic unsaturated aliphatic hydrocarbon groups having 3 to 20 carbon atoms such as cyclohexenyl and norbornenyl; aryl groups having 6 to 20 carbon atoms such as phenyl, methylphenyl, ethylphenyl, n-propylphenyl, isopropylphenyl, n-butylphenyl, isobutylphenyl, sec-butylphenyl, tert-butylphenyl, naphthyl, methylnaphthyl, ethylnaphthyl, n-propylnaphthyl, isopropylnaphthyl, n-butylnaphthyl, isobutylnaphthyl, sec-butylnaphthyl and tert-butylnaphthyl; aralkyl groups having 7 to 20 carbon atoms such as benzyl and phenethyl; groups obtained by combining them, etc.

[0093] In addition, a part or all of the hydrogen atoms of the aforementioned hydrocarbon group may be optionally substituted by a group containing a hetero atom such as an oxygen atom, a sulfur atom, a nitrogen atom, or a halogen atom, and a part of the aforementioned hydrocarbon group -CH2- may be optionally replaced by a group containing a hetero atom such as an oxygen atom, a sulfur atom, a nitrogen atom, or the like. As a result, it may optionally contain a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a nitro group, a mercapto group, a carbonyl group, an ether bond, an ester bond, a sulfonate bond, a carbonate bond, a lactone ring, a sultone ring, a carboxylic anhydride (-C(=O)-OC(=O)-), a haloalkyl group, or the like.

[0094] In addition, R 2 and R 3 They may be bonded to each other to form a ring together with the sulfur atom to which they are bonded. In this case, the ring preferably has the structure shown below.

[0095]

[0096] (In the formula, the dotted line represents the connecting bond.)

[0097] Specific examples of the sulfonium cation include the following, but are not limited to these.

[0098]

[0099]

[0100]

[0101]

[0102]

[0103]

[0104]

[0105]

[0106]

[0107]

[0108]

[0109]

[0110]

[0111]

[0112]

[0113]

[0114]

[0115] Examples of the iodonium cation include the iodonium cations shown below, but the iodonium cations are not limited to these.

[0116]

[0117] As a method for synthesizing a sulfonium salt monomer providing a repeating unit a, a method of ion-exchanging a salt formed by the sulfonium cation and a weak acid anion with an ammonium salt having the anion can be cited. The sulfonium cation can be obtained by, for example, the method described in paragraphs

[0094] to

[0097] of Japanese Patent Application Laid-Open No. 2022-68394. In the case of an iodonium salt monomer, the same ion exchange method as described above can be cited.

[0118] In the case of a positive type resist material, the base polymer preferably further comprises a repeating unit containing an acid labile group. As a repeating unit containing an acid labile group, it is preferably a repeating unit shown in the following formula (b1) (hereinafter also referred to as repeating unit b1) or a repeating unit shown in the following formula (b2) (hereinafter also referred to as repeating unit b2). In the exposure portion, not only the repeating unit b1 or b2 containing an acid labile group in the base polymer, but also the repeating unit a containing an acid generator will also be accelerated by the catalytic reaction relative to the developer, and therefore, a positive type resist material with extremely high sensitivity can be made.

[0119]

[0120] In formula (b1) and (b2), R A Each is independently a hydrogen atom or a methyl group. 1 Y is a single bond, a linking group having 1 to 12 carbon atoms and containing at least one selected from a phenylene group or a naphthylene group, or an ester bond, an ether bond, a lactone ring, a hydroxyl group, and a halogen atom. 2 is a single bond or an ester bond. 3 is a single bond, an ether bond or an ester bond. 11 and R 12 Each is independently an acid-labile group. 13 R is a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a trifluoromethyl group, a cyano group, a saturated hydrocarbon group having 1 to 6 carbon atoms, a saturated hydrocarbonoxy group having 1 to 6 carbon atoms, a saturated hydrocarboncarbonyl group having 2 to 7 carbon atoms, a saturated hydrocarboncarbonyloxy group having 2 to 7 carbon atoms, or a saturated hydrocarbonoxycarbonyl group having 2 to 7 carbon atoms. 14 It is a single bond or an alkanediyl group having 1 to 6 carbon atoms, and a part of the alkanediyl group -CH2- is optionally replaced by an ether bond or an ester bond. a is 1 or 2. b is an integer from 0 to 4. 1≤a+b≤5.

[0121] Examples of monomers that provide the repeating unit b1 include the following monomers, but are not limited thereto. A and R 11 Same as above.

[0122]

[0123] As the monomer providing the repeating unit b2, the following monomers can be cited, but are not limited thereto. A and R 12 Same as above.

[0124]

[0125] In formulas (b1) and (b2), R11 and R 12 Examples of the acid-labile group include groups described in JP-A-2013-80033 and JP-A-2013-83821.

[0126] Typically, the acid-labile group includes groups represented by the following formulae (AL-1) to (AL-3).

[0127]

[0128] (In the formula, the dashed line is the connecting bond.)

[0129] In formula (AL-1) and (AL-2), R L1 and R L2 Each is independently a hydrocarbon group having 1 to 40 carbon atoms, and may contain heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and fluorine atoms. The hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. The hydrocarbon group is preferably a saturated hydrocarbon group having 1 to 40 carbon atoms or an unsaturated hydrocarbon group having 2 to 40 carbon atoms, and more preferably a saturated hydrocarbon group having 1 to 20 carbon atoms or an unsaturated hydrocarbon group having 2 to 20 carbon atoms.

[0130] In the formula (AL-1), c is an integer of 0-10, and preferably an integer of 1-5.

[0131] In formula (AL-2), R L3 and R L4 Each independently represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and may optionally contain heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and fluorine atoms. The hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. The hydrocarbon group is preferably a saturated hydrocarbon group having 1 to 20 carbon atoms. L2 , R L3 and R L4 Any two of the above may be bonded to each other to form a ring having 3 to 20 carbon atoms together with the carbon atom or the carbon atom and oxygen atom to which they are bonded. The above ring is preferably a ring having 4 to 16 carbon atoms, and is particularly preferably an alicyclic ring.

[0132] In formula (AL-3), R L5 , R L6 and R L7 Each independently represents a hydrocarbon group having 1 to 20 carbon atoms, and may contain heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and fluorine atoms. The hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. The hydrocarbon group is preferably a saturated hydrocarbon group having 1 to 20 carbon atoms. L5 , RL6 and R L7 Any two of them may be bonded to each other to form a ring having 3 to 20 carbon atoms together with the carbon atoms to which they are bonded. The ring is preferably a ring having 4 to 16 carbon atoms, particularly preferably an alicyclic ring, and the ring may have a double bond or a triple bond.

[0133] As the acid-labile group represented by formula (AL-3), an acid-labile group containing an aromatic group described in Japanese Patent No. 5655754, Japanese Patent No. 5655755, Japanese Patent No. 5655756, Japanese Patent No. 5407941, Japanese Patent No. 5434983, Japanese Patent No. 5565293 and Japanese Patent Publication No. 2007-279699; an acid-labile group containing a triple bond described in Japanese Patent Publication No. 2008-268741; and an acid-labile group containing a double bond or a triple bond described in Japanese Patent Publication No. 2021-50307 can also be used.

[0134] The base polymer may further include a repeating unit c containing a phenolic hydroxyl group as an adhesive group. The monomers providing the repeating unit c include the following monomers, but are not limited to them. It should be noted that in the following formula, R A Same as above.

[0135]

[0136] The base polymer may include, as other adhesive groups, repeating units d containing hydroxyl groups other than phenolic hydroxyl groups, lactone rings, sultone rings, ether bonds, ester bonds, sulfonate bonds, carbonyl groups, sulfonyl groups, cyano groups, or carboxyl groups. The monomers providing the repeating units d include the following monomers, but are not limited to them. It should be noted that in the following formula, R A Same as above.

[0137]

[0138]

[0139]

[0140]

[0141]

[0142]

[0143]

[0144]

[0145] The aforementioned base polymer may further contain repeating unit e derived from indene, benzofuran, benzothiophene, acenaphthylene, chromone, coumarin, norbornadiene, or derivatives thereof. As monomers providing repeating unit e, the monomers shown below can be cited, but are not limited thereto.

[0146]

[0147] The aforementioned base polymer may further contain repeating unit f derived from styrene, vinylnaphthalene, vinylanthracene, vinylpyrene, methyleneindan, vinylpyridine, or vinylcarbazole.

[0148] The aforementioned base polymer necessarily has repeating unit a. When repeating unit a is repeating unit a1 or a2, the content ratios of repeating units a1, a2, b, c, d, e, and f are preferably 0 ≤ a1 ≤ 0.5, 0 ≤ a2 ≤ 0.5, 0 < a1 + a2 ≤ 0.5, 0 ≤ b1 ≤ 0.8, 0 ≤ b2 ≤ 0.8, 0.1 ≤ b1 + b2 ≤ 0.8, 0 ≤ c ≤ 0.9, 0 ≤ d ≤ 0.8, 0 ≤ e ≤ 0.8, and 0 ≤ f ≤ 0.5, more preferably 0 ≤ a1 ≤ 0.4, 0 ≤ a2 ≤ 0.4, 0.02 ≤ a1 + a2 ≤ 0.4, 0 ≤ b1 ≤ 0.7, 0 ≤ b2 ≤ 0.7, 0.15 ≤ b1 + b2 ≤ 0.7, 0 ≤ c ≤ 0.8, 0 ≤ d ≤ 0.7, 0 ≤ e ≤ 0.7, and 0 ≤ f ≤ 0.4, and still more preferably 0 ≤ a1 ≤ 0.35, 0 ≤ a2 ≤ 0.35, 0.05 ≤ a1 + a2 ≤ 0.35, 0 ≤ b1 ≤ 0.65, 0 ≤ b2 ≤ 0.65, 0.2 ≤ b1 + b2 ≤ 0.65, 0 ≤ c ≤ 0.7, 0 ≤ d ≤ 0.6, 0 ≤ e ≤ 0.6, and 0 ≤ f ≤ 0.3. It should be noted that a1 + a2 + b1 + b2 + c + d + e + f = 1.0.

[0149] To synthesize the aforementioned base polymer, for example, with respect to the monomers providing the aforementioned repeating units, it is only necessary to add a radical polymerization initiator to an organic solvent and heat for polymerization.

[0150] As the organic solvent used in the polymerization, toluene, benzene, tetrahydrofuran (THF), diethyl ether, dioxane, etc. can be cited. As the polymerization initiator, 2,2'-azobisisobutyronitrile (AIBN), 2,2'-azobis(2,4-dimethylvaleronitrile), dimethyl-2,2-azobis(2-methylpropionate), benzoyl peroxide, lauroyl peroxide, etc. can be cited. The temperature during polymerization is preferably 50 to 80°C. The reaction time is preferably 2 to 100 hours, more preferably 5 to 20 hours.

[0151] When copolymerizing monomers containing a hydroxyl group, the hydroxyl group may be replaced with an acetal group such as ethoxyethoxy that is easily deprotected by an acid during polymerization, and then deprotected using a weak acid and water after polymerization. Alternatively, the hydroxyl group may be replaced with an acetyl group, a formyl group, a pivaloyl group, etc., and then hydrolyzed with an alkali after polymerization.

[0152] When hydroxystyrene and hydroxyvinylnaphthalene are copolymerized, acetoxystyrene and acetoxyvinylnaphthalene may be used instead of hydroxystyrene and hydroxyvinylnaphthalene, and after polymerization, the acetoxy group may be deprotected by the above-mentioned alkaline hydrolysis to obtain hydroxystyrene and hydroxyvinylnaphthalene.

[0153] As the base for alkaline hydrolysis, aqueous ammonia, triethylamine, etc. can be used. The reaction temperature is preferably -20 to 100° C., more preferably 0 to 60° C. The reaction time is preferably 0.2 to 100 hours, more preferably 0.5 to 20 hours.

[0154] The polystyrene-equivalent weight average molecular weight (Mw) of the base polymer measured by gel permeation chromatography (GPC) using THF as a solvent is preferably 1000 to 500000, more preferably 2000 to 30000. When Mw is within the above range, the heat resistance and solubility in an alkaline developer of the resist film are good.

[0155] In addition, when the molecular weight distribution (Mw / Mn) of the aforementioned base polymer is wide, there will be low molecular weight and high molecular weight polymers, so it is possible that foreign matter is observed on the pattern after exposure or the shape of the pattern is deteriorated. As the pattern rules become finer, the influence of Mw and Mw / Mn tends to become greater. Therefore, in order to obtain a resist material suitable for a fine pattern size, the Mw / Mn of the aforementioned base polymer is preferably narrowly dispersed to 1.0 to 2.0, and particularly preferably narrowly dispersed to 1.0 to 1.5.

[0156] In order to obtain a narrowly dispersed polymer, not only conventional radical polymerization but also living radical polymerization can be used. Examples of living radical polymerization include living radical polymerization using nitroxide radicals (Nitroxide-Mediated Radical Polymerization: NMP), atom transfer radical polymerization (Atom Transfer Radical Polymerization: ATRP), and reversible addition-fragmentation chain transfer (Reversible Addition-Fragmentation Chain Transfer: RAFT) polymerization.

[0157] The base polymer may include two or more polymers having different composition ratios, Mw, and Mw / Mn.

[0158] [Organic solvents]

[0159] The anti-etching material of the present invention may contain an organic solvent. The aforementioned organic solvent is not particularly limited as long as it can dissolve the aforementioned components and the components described below. Examples of the aforementioned organic solvent include ketones such as cyclohexanone, cyclopentanone, methyl-2-n-pentyl ketone, and 2-heptanone described in paragraphs

[0144] to

[0145] of Japanese Patent Publication No. 2008-111103; alcohols such as 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, and diacetone alcohol; propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, and ethylene glycol monoethyl ether. Ethers such as propylene glycol dimethyl ether and diethylene glycol dimethyl ether; esters such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl lactate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, tert-butyl acetate, tert-butyl propionate, propylene glycol mono-tert-butyl ether acetate, methyl 2-hydroxyisobutyrate, ethyl 2-hydroxyisobutyrate, propyl 2-hydroxyisobutyrate, butyl 2-hydroxyisobutyrate; lactones such as γ-butyrolactone, etc.

[0160] In the resist material of the present invention, the content of the organic solvent is preferably 100 to 10,000 parts by mass, more preferably 200 to 8,000 parts by mass, based on 100 parts by mass of the base polymer. The organic solvent may be used alone or in combination of two or more.

[0161] [Acid generator]

[0162] The positive resist material of the present invention may further include an acid generator (hereinafter also referred to as an additive acid generator) that generates a strong acid. The strong acid mentioned here refers to a compound having sufficient acidity for the deprotection reaction of the acid-labile group of the base polymer. As the aforementioned acid generator, for example, a compound (photoacid generator) that generates an acid by induction of active light or radiation can be cited. As a photoacid generator, any photoacid generator can be used as long as it is a compound that generates an acid by irradiation with high-energy rays, and preferably a photoacid generator that generates sulfonic acid, imidic acid or methylated acid. As suitable photoacid generators, there are sulfonium salts, iodonium salts, sulfonyldiazomethane, N-sulfonyloxyimide, oxime-O-sulfonate acid generators, etc. As specific examples of photoacid generators, examples recorded in paragraphs

[0122] to

[0142] of Japanese Patent Publication No. 2008-111103 can be cited.

[0163] In addition, as the photoacid generator, a sulfonium salt represented by the following formula (1-1) or an iodonium salt represented by the following formula (1-2) can also be preferably used.

[0164]

[0165] In formula (1-1) and (1-2), R 101 ~R 105 Each is independently a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms, which may contain a hetero atom. The hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include the same as those described for R in formulas (M-1) and (M-2): 2 ~R 6 The hydrocarbon group shown is the same as the group exemplified. 101 and R 102 The rings may be bonded to each other to form a ring together with the sulfur atom to which they are bonded. In this case, examples of the ring include the same as those mentioned as R in the description of formulae (M-1) and (M-2). 2 and R 3 The rings are the same as those exemplified above and can form a ring together with the sulfur atom to which they are bonded.

[0166] In formula (1-1) and (1-2), Xa - It is an anion selected from the following formulae (1A) to (1D).

[0167]

[0168] In formula (1A), R fa is a fluorine atom or a hydrocarbon group having 1 to 40 carbon atoms which may contain a hetero atom. The hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include the following: fa1 The hydrocarbon groups shown are the same groups as those exemplified.

[0169] As the anion represented by the formula (1A), an anion represented by the following formula (1A′) is preferred.

[0170]

[0171] In formula (1A'), R HF is a hydrogen atom or a trifluoromethyl group, preferably a trifluoromethyl group. fa1 The hydrocarbon group is a hydrocarbon group having 1 to 38 carbon atoms and optionally containing a hetero atom. The hetero atom is preferably an oxygen atom, a nitrogen atom, a sulfur atom, a halogen atom, etc., and more preferably an oxygen atom. The hydrocarbon group is particularly preferably a hydrocarbon group having 6 to 30 carbon atoms from the viewpoint of obtaining a high resolution in fine pattern formation.

[0172] R fa1The hydrocarbon group shown may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include alkyl groups having 1 to 38 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, pentyl, neopentyl, hexyl, heptyl, 2-ethylhexyl, nonyl, undecyl, tridecyl, pentadecyl, heptadecyl, and eicosyl; cyclic saturated hydrocarbon groups having 3 to 38 carbon atoms, such as cyclopentyl, cyclohexyl, 1-adamantyl, 2-adamantyl, 1-adamantylmethyl, norbornyl, norbornylmethyl, tricyclodecanyl, tetracyclododecyl, tetracyclododecylmethyl, and dicyclohexylmethyl; unsaturated hydrocarbon groups having 2 to 38 carbon atoms, such as allyl and 3-cyclohexenyl; aryl groups having 6 to 38 carbon atoms, such as phenyl, 1-naphthyl, and 2-naphthyl; aralkyl groups having 7 to 38 carbon atoms, such as benzyl and diphenylmethyl; and groups obtained by combining these.

[0173] In addition, part or all of the hydrogen atoms of the aforementioned hydrocarbon group may be substituted by a group containing a hetero atom such as an oxygen atom, a sulfur atom, a nitrogen atom, or a halogen atom, and part of the aforementioned hydrocarbon group -CH2- may be replaced by a group containing a hetero atom such as an oxygen atom, a sulfur atom, or a nitrogen atom, and as a result, a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a nitro group, a carbonyl group, an ether bond, an ester bond, a sulfonate bond, a carbonate bond, a lactone ring, a sultone ring, a carboxylic anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc. may be optionally contained. Examples of the hydrocarbon group containing a hetero atom include a tetrahydrofuranyl group, a methoxymethyl group, an ethoxymethyl group, a methylthiomethyl group, an acetamidomethyl group, a trifluoroethyl group, a (2-methoxyethoxy)methyl group, an acetoxymethyl group, a 2-carboxy-1-cyclohexyl group, a 2-oxopropyl group, a 4-oxo-1-adamantyl group, and a 3-oxocyclohexyl group.

[0174] For the synthesis of the sulfonium salt containing the anion represented by formula (1A'), see Japanese Patent Publication No. 2007-145797, Japanese Patent Publication No. 2008-106045, Japanese Patent Publication No. 2009-7327, Japanese Patent Publication No. 2009-258695, etc. In addition, the sulfonium salts described in Japanese Patent Publication No. 2010-215608, Japanese Patent Publication No. 2012-41320, Japanese Patent Publication No. 2012-106986, Japanese Patent Publication No. 2012-153644, etc. can also be suitably used.

[0175] Examples of the anion represented by formula (1A) include the same anions as those exemplified as the anion represented by formula (1A) in JP-A-2018-197853.

[0176] In formula (1B), R fb1 and R fb2Each independently represents a fluorine atom or a hydrocarbon group having 1 to 40 carbon atoms and optionally containing a heteroatom. The hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include the following: fa1 The hydrocarbon group shown in the figure is the same group as the group exemplified. fb1 and R fb2 , preferably a fluorine atom or a linear fluoroalkyl group having 1 to 4 carbon atoms. fb1 With R fb2 Optionally bonded to each other and to the groups to which they are bonded (-CF2-SO2-N - -SO2-CF2-) together to form a ring, at this time, R fb1 With R fb2 The groups obtained by bonding to each other are preferably fluoroethylene groups or fluoropropylene groups.

[0177] In formula (1C), R fc1 , R fc2 and R fc3 Each independently represents a fluorine atom or a hydrocarbon group having 1 to 40 carbon atoms and optionally containing a heteroatom. The hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include the following: fa1 The hydrocarbon group shown in the figure is the same group as the group exemplified. fc1 , R fc2 and R fc3 , preferably a fluorine atom or a linear fluoroalkyl group having 1 to 4 carbon atoms. fc1 With R fc2 Optionally bonded to each other and to the groups to which they are bonded (-CF2-SO2-C - -SO2-CF2-) together to form a ring, at this time, R fc1 With R fc2 The groups obtained by bonding to each other are preferably fluoroethylene groups or fluoropropylene groups.

[0178] In formula (1D), R fd is a hydrocarbon group having 1 to 40 carbon atoms and optionally containing a heteroatom. The hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include the following: fa1 The hydrocarbon groups shown are the same groups as those exemplified.

[0179] For details on the synthesis of the sulfonium salt containing the anion represented by the formula (1D), see Japanese Patent Application Laid-Open Nos. 2010-215608 and 2014-133723.

[0180] Examples of the anion represented by the formula (1D) include the same anions as those exemplified as the anion represented by the formula (1D) in JP-A-2018-197853.

[0181] It should be noted that the photoacid generator containing the anion represented by formula (1D) has no fluorine atom at the α position of the sulfonic group but has two trifluoromethyl groups at the β position, and therefore has sufficient acidity to cleave the acid-labile group in the base polymer. Therefore, it can be used as a photoacid generator.

[0182] Furthermore, as the photoacid generator, a photoacid generator represented by the following formula (2) can also be preferably used.

[0183]

[0184] In formula (2), R 201 and R 202 Each is independently a halogen atom or a hydrocarbon group having 1 to 30 carbon atoms which may contain a hetero atom. 203 is a alkylene group having 1 to 30 carbon atoms which may contain a hetero atom. 201 , R 202 and R 203 Any two of them are optionally bonded to each other to form a ring together with the sulfur atom to which they are bonded. In this case, examples of the aforementioned ring include the same as those mentioned as R in the description of formulas (M-1) and (M-2). 2 and R 3 The rings are the same as those exemplified above and can form a ring together with the sulfur atom to which they are bonded.

[0185] R 201 and R 202 The hydrocarbon group shown may be saturated or unsaturated, and may be any of linear, branched, and cyclic. Specific examples thereof include alkyl groups having 1 to 30 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, tert-pentyl, n-hexyl, n-octyl, 2-ethylhexyl, n-nonyl, and n-decyl; cyclopentyl, cyclohexyl, cyclopentylmethyl, cyclopentylethyl, cyclopentylbutyl, cyclohexylmethyl, cyclohexylethyl, cyclohexylbutyl, norbornyl, tricyclo[5.2.1.0 2,6] cyclic saturated hydrocarbon groups having 3 to 30 carbon atoms, such as decyl and adamantyl; aryl groups having 6 to 30 carbon atoms, such as phenyl, methylphenyl, ethylphenyl, n-propylphenyl, isopropylphenyl, n-butylphenyl, isobutylphenyl, sec-butylphenyl, tert-butylphenyl, naphthyl, methylnaphthyl, ethylnaphthyl, n-propylnaphthyl, isopropylnaphthyl, n-butylnaphthyl, isobutylnaphthyl, sec-butylnaphthyl, tert-butylnaphthyl and anthracenyl; groups obtained by combining them, etc. In addition, a part or all of the hydrogen atoms of the aforementioned hydrocarbon group may be optionally substituted by a group containing a hetero atom such as an oxygen atom, a sulfur atom, a nitrogen atom, or a halogen atom, and a part of the aforementioned hydrocarbon group -CH2- may be optionally replaced by a group containing a hetero atom such as an oxygen atom, a sulfur atom, a nitrogen atom, etc. As a result, it may optionally contain a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a carbonyl group, an ether bond, an ester bond, a sulfonate bond, a carbonate bond, a lactone ring, a sultone ring, a carboxylic anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc.

[0186] R 203 The alkylene group shown may be saturated or unsaturated, and may be any of a straight chain, a branched chain, or a cyclic chain. Specific examples thereof include methanediyl, ethane-1,1-diyl, ethane-1,2-diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, decane-1,10-diyl, undecane-1,11-diyl, dodecane-1,12-diyl, tridecane-1,13-diyl, tetradecane-1,14-diyl, pentadecane-1,15-diyl, hexadecane-1,16-diyl, heptadecane-1,17-diyl, and octadecane-1,18-diyl. Alkanediyl groups having 1 to 30 carbon atoms such as cyclopentanediyl, cyclohexanediyl, norbornanediyl and adamantanediyl; arylene groups having 6 to 30 carbon atoms such as phenylene, methylphenylene, ethylphenylene, n-propylphenylene, isopropylphenylene, n-butylphenylene, isobutylphenylene, sec-butylphenylene, tert-butylphenylene, naphthylene, methylnaphthylene, ethylnaphthylene, n-propylnaphthylene, isopropylnaphthylene, n-butylnaphthylene, isobutylnaphthylene, sec-butylnaphthylene and tert-butylnaphthylene; groups obtained by combining these groups, etc. In addition, part or all of the hydrogen atoms of the aforementioned alkylene group may be substituted by a group containing a hetero atom such as an oxygen atom, a sulfur atom, a nitrogen atom, or a halogen atom, and part of the aforementioned alkylene group -CH2- may be replaced by a group containing a hetero atom such as an oxygen atom, a sulfur atom, or a nitrogen atom, and as a result, a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a nitro group, a carbonyl group, an ether bond, an ester bond, a sulfonate bond, a carbonate bond, a lactone ring, a sultone ring, a carboxylic anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc. may be optionally contained. As the aforementioned hetero atom, an oxygen atom is preferably used.

[0187] In formula (2), L A is a single bond, an ether bond, or an alkylene group having 1 to 20 carbon atoms and optionally containing a hetero atom. The alkylene group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include the following: 203 The same groups as those exemplified for the alkylene groups shown in FIG.

[0188] In formula (2), X A , X B , X C and X D Each independently represents a hydrogen atom, a fluorine atom or a trifluoromethyl group. A , X B , X C and X D At least one of them is a fluorine atom or a trifluoromethyl group.

[0189] In formula (2), k is an integer from 0 to 3.

[0190] The photoacid generator represented by the formula (2) is preferably a photoacid generator represented by the following formula (2').

[0191]

[0192] In formula (2'), L A Same as above. X e is a hydrogen atom or a trifluoromethyl group, preferably a trifluoromethyl group. 301 , R 302 and R 303 Each is independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms and optionally containing a heteroatom. The hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include the following: fa1 The hydrocarbon groups shown in the figure are the same as the groups exemplified above. x and y are each independently an integer of 0 to 5, and z is an integer of 0 to 4.

[0193] Examples of the photoacid generator represented by formula (2) include the same substances as those exemplified as the photoacid generator represented by formula (2) in JP-A-2017-026980.

[0194] Among the above-mentioned photoacid generators, the photoacid generator containing an anion represented by formula (1A') or (1D) is particularly preferred because it has low acid diffusion and excellent solubility in solvents. In addition, the photoacid generator represented by formula (2') is particularly preferred because it has extremely low acid diffusion.

[0195] As the photoacid generator, a sulfonium salt or iodonium salt having an anion containing an aromatic ring substituted with an iodine atom or a bromine atom may be used. Examples of such salts include salts represented by the following formula (3-1) or (3-2).

[0196]

[0197] In formulas (3-1) and (3-2), p is an integer satisfying 1≤p≤3. q and r are integers satisfying 1≤q≤5, 0≤r≤3, and 1≤q+r≤5. q is preferably an integer satisfying 1≤q≤3, more preferably 2 or 3. r is preferably an integer satisfying 0≤r≤2.

[0198] In formulas (3-1) and (3-2), X BI is an iodine atom or a bromine atom, and when p and / or q is 2 or more, they may be the same as or different from each other.

[0199] In formulas (3-1) and (3-2), L 1 It is a single bond, an ether bond or an ester bond, or a saturated alkylene group having 1 to 6 carbon atoms which may contain an ether bond or an ester bond. The saturated alkylene group may be linear, branched or cyclic.

[0200] In formulas (3-1) and (3-2), when p is 1, L 2 is a single bond or a divalent linking group having 1 to 20 carbon atoms, and when p is 2 or 3, L 2 It is a (p+1)-valent linking group having 1 to 20 carbon atoms, and the linking group may contain an oxygen atom, a sulfur atom or a nitrogen atom.

[0201] In formulas (3-1) and (3-2), R 401 is a hydroxyl group, a carboxyl group, a fluorine atom, a chlorine atom, a bromine atom or an amino group; or a hydrocarbon group having 1 to 20 carbon atoms, a hydrocarbonoxy group having 1 to 20 carbon atoms, a hydrocarboncarbonyl group having 2 to 20 carbon atoms, a hydrocarbonoxycarbonyl group having 2 to 10 carbon atoms, a hydrocarboncarbonyloxy group having 2 to 20 carbon atoms or a hydrocarbonsulfonyloxy group having 1 to 20 carbon atoms, which may contain a fluorine atom, a chlorine atom, a bromine atom, a hydroxyl group, an amino group or an ether bond; or -N(R 401A )(R 401B )、-N(R 401C )-C(=O)-R 401D or -N(R 401C )-C(=O)-OR 401D . R 401A and R 401B Each R is independently a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms. 401CR is a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms, which may contain a halogen atom, a hydroxyl group, a saturated hydrocarbonoxy group having 1 to 6 carbon atoms, a saturated hydrocarboncarbonyl group having 2 to 6 carbon atoms, or a saturated hydrocarboncarbonyloxy group having 2 to 6 carbon atoms. 401D It is an aliphatic hydrocarbon group having 1 to 16 carbon atoms, an aryl group having 6 to 14 carbon atoms, or an aralkyl group having 7 to 15 carbon atoms, and may contain a halogen atom, a hydroxyl group, a saturated hydrocarbonoxy group having 1 to 6 carbon atoms, a saturated hydrocarboncarbonyl group having 2 to 6 carbon atoms, or a saturated hydrocarboncarbonyloxy group having 2 to 6 carbon atoms. The aforementioned aliphatic hydrocarbon group may be saturated or unsaturated, and may be any of a straight chain, a branched chain, or a cyclic chain. The aforementioned hydrocarbon group, hydrocarbonoxy group, hydrocarbonoxycarbonyl group, hydrocarboncarbonyl group, hydrocarboncarbonyloxy group, and hydrocarbonsulfonyloxy group may be any of a straight chain, a branched chain, or a cyclic chain. When p and / or r are 2 or more, each R 401 They are optionally the same as or different from each other.

[0202] Among these, R 401 , preferably hydroxyl, -N(R 401C )-C(=O)-R 401D 、-N(R 401C )-C(=O)-OR 401D , fluorine atom, chlorine atom, bromine atom, methyl group, methoxy group and the like.

[0203] In formula (3-1) and (3-2), Rf 1 ~Rf 4 Each independently represents a hydrogen atom, a fluorine atom or a trifluoromethyl group, and at least one of these is a fluorine atom or a trifluoromethyl group. 1 With Rf 2 Optionally, they may also form a carbonyl group. 3 and Rf 4 All are fluorine atoms.

[0204] In formulas (3-1) and (3-2), R 402 ~R 406 Each independently represents a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms and optionally containing a heteroatom. The hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include the same as those used as R in the description of formulas (M-1) and (M-2): 2 ~R 6 The hydrocarbon group shown in the figure is the same as the group exemplified in the figure. In addition, some or all of the hydrogen atoms of the aforementioned hydrocarbon group may be substituted with a hydroxyl group, a carboxyl group, a halogen atom, a cyano group, a nitro group, a mercapto group, a sultone group, a sulfonium group or a group containing a sulfonium salt, and a part of the aforementioned hydrocarbon group -CH2- may be replaced with an ether bond, an ester bond, a carbonyl group, an amide bond, a carbonate bond or a sulfonate bond. Furthermore, R 402 and R 403The rings may be bonded to each other to form a ring together with the sulfur atom to which they are bonded. In this case, examples of the ring include the same as those mentioned as R in the description of formulae (M-1) and (M-2). 2 and R 3 The rings are the same as those exemplified above and can form a ring together with the sulfur atom to which they are bonded.

[0205] Examples of the cation of the sulfonium salt represented by the formula (3-1) include the cations corresponding to M in the formulas (a1) and (a2). + The sulfonium cations shown in the formula (3-2) are the same as those shown in the formula (a1) and (a2). + The iodonium cations shown and exemplified are the same iodonium cations.

[0206] Examples of the anion of the onium salt represented by formula (3-1) or (3-2) include the anions shown below, but are not limited to these. BI Same as above.

[0207]

[0208]

[0209]

[0210]

[0211]

[0212]

[0213]

[0214]

[0215]

[0216]

[0217]

[0218]

[0219]

[0220]

[0221]

[0222]

[0223]

[0224]

[0225]

[0226]

[0227]

[0228] As the photoacid generator, a sulfonium salt or iodonium salt of fluorobenzenesulfonic acid bonded with iodinated benzoic acid represented by the following formula (3-3) or (3-4) may be used.

[0229]

[0230] In formulas (3-3) and (3-4), n1 is an integer of 1 to 5. n2 is an integer of 0 to 3. n3 is an integer of 1 to 4.

[0231] In formulas (3-3) and (3-4), R 411 is a hydroxyl group, a carboxyl group, an alkoxycarbonyl group, a fluorine atom, a chlorine atom, a bromine atom, or an amino group; or a saturated hydrocarbon group having 1 to 20 carbon atoms, a saturated hydrocarbonoxy group having 1 to 20 carbon atoms, or a saturated hydrocarboncarbonyloxy group having 2 to 20 carbon atoms, which may contain a fluorine atom, a chlorine atom, a bromine atom, a hydroxyl group, an amino group, or an alkoxy group; or -N(R 411A )-C(=O)-R 411B or -N(R 411A )-C(=O)-OR 411B , R 411A R is a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms. 411B It is an aliphatic hydrocarbon group having 1 to 16 carbon atoms, an aryl group having 6 to 14 carbon atoms, or an aralkyl group having 7 to 15 carbon atoms, and optionally contains a halogen atom, a hydroxyl group, a saturated hydrocarbonoxy group having 1 to 6 carbon atoms, a saturated hydrocarboncarbonyl group having 2 to 6 carbon atoms, or a saturated hydrocarboncarbonyloxy group having 2 to 6 carbon atoms.

[0232] In formulas (3-3) and (3-4), L 3 It is a single bond or a divalent linking group having 1 to 20 carbon atoms, and the linking group may contain an oxygen atom, a sulfur atom or a nitrogen atom.

[0233] In formula (3-3) and (3-4), Rf 11 is a fluorine atom or a trifluoromethyl group.

[0234] In formulas (3-3) and (3-4), R412 ~R 416 Each independently represents a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms and optionally containing a heteroatom. The hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include the same as those used as R in the description of formulas (M-1) and (M-2): 2 ~R 6 The hydrocarbon group shown in the figure is the same as the group exemplified in the figure. In addition, some or all of the hydrogen atoms of the aforementioned hydrocarbon group may be substituted with a hydroxyl group, a carboxyl group, a halogen atom, a cyano group, a nitro group, a mercapto group, a sultone group, a sulfonium group or a group containing a sulfonium salt, and a part of the aforementioned hydrocarbon group -CH2- may be replaced with an ether bond, an ester bond, a carbonyl group, an amide bond, a carbonate bond or a sulfonate bond. Furthermore, R 402 and R 403 The rings may be bonded to each other to form a ring together with the sulfur atom to which they are bonded. In this case, examples of the ring include the same as those mentioned as R in the description of formulae (M-1) and (M-2). 2 and R 3 The rings are the same as those exemplified above and can form a ring together with the sulfur atom to which they are bonded.

[0235] Examples of the cation of the sulfonium salt represented by the formula (3-3) include the cations corresponding to M in the formulas (a1) and (a2). + The sulfonium cations shown in the formula (3-4) are the same as those shown in the formula (a1) and (a2). + The iodonium cations shown and exemplified are the same iodonium cations.

[0236] Examples of the anion of the onium salt represented by the formula (3-3) or (3-4) include the anions shown below, but are not limited to these.

[0237]

[0238]

[0239]

[0240]

[0241]

[0242] When the anti-corrosion material of the present invention contains the aforementioned additive acid generator, its content is preferably 0.1 to 50 parts by mass, and more preferably 1 to 40 parts by mass relative to 100 parts by mass of the aforementioned base polymer. The aforementioned additive acid generator can be used alone or in combination of two or more. By making the aforementioned base polymer contain repeating unit a, and / or, by containing an additive acid generator, the anti-corrosion material of the present invention can function as a chemically amplified anti-corrosion material.

[0243] [Quencher]

[0244] The resist material of the present invention may contain a quencher. The quencher is a compound that can prevent the acid generated by the acid generator in the resist material from diffusing to the unexposed area by trapping the acid.

[0245] As the aforementioned quencher, existing basic compounds can be cited. As existing basic compounds, primary, secondary, and tertiary aliphatic amines, mixed amines, aromatic amines, heterocyclic amines, nitrogen-containing compounds having carboxyl groups, nitrogen-containing compounds having sulfonyl groups, nitrogen-containing compounds having hydroxyl groups, nitrogen-containing compounds having hydroxyphenyl groups, alcoholic nitrogen-containing compounds, amides, imides, and carbamates can be cited. In particular, the primary, secondary, and tertiary amine compounds described in paragraphs

[0146] to

[0164] of Japanese Patent Publication No. 2008-111103 are preferred, and amine compounds having hydroxyl groups, ether bonds, ester bonds, lactone rings, cyano groups, and sulfonate bonds or compounds having carbamate groups described in Japanese Patent Publication No. 3790649 are particularly preferred. By adding such basic compounds, it is possible to further suppress the diffusion rate of acid in the resist film or to trim the shape, for example.

[0246] In addition, as the above-mentioned quencher, there can be mentioned onium salts such as sulfonium salts, iodonium salts, and ammonium salts of sulfonic acids, carboxylic acids, or fluorinated alkoxides at the α-position that are not fluorinated as described in Japanese Patent Application Laid-Open No. 2008-158339. The sulfonic acid, imidic acid, or methylated acid at the α-position that is fluorinated is necessary for deprotecting the acid-labile group of the carboxylate, but the sulfonic acid, carboxylic acid, or fluoroalcohol at the α-position that is not fluorinated is released by salt exchange with the onium salt at the α-position that is not fluorinated. Since the sulfonic acid, carboxylic acid, and fluorinated alcohol at the α-position that are not fluorinated do not undergo deprotection reaction, they function as quenchers.

[0247] Examples of such quenchers include compounds represented by the following formula (4-1) (onium salt of sulfonic acid not fluorinated at the α-position), compounds represented by the following formula (4-2) (onium salt of carboxylic acid), and compounds represented by the following formula (4-3) (onium salt of alkoxide).

[0248]

[0249] In formula (4-1), R 501 It is a hydrogen atom or a hydrocarbon group having 1 to 40 carbon atoms which may contain a hetero atom, but does not include a group in which the hydrogen atom bonded to the carbon atom at the α position of the sulfonic group is substituted by a fluorine atom or a fluoroalkyl group.

[0250] R 501 The hydrocarbon group having 1 to 40 carbon atoms shown in the figure may be saturated or unsaturated, and may be any of linear, branched, and cyclic. Specific examples thereof include alkyl groups having 1 to 40 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, tert-pentyl, n-hexyl, n-octyl, 2-ethylhexyl, n-nonyl, and n-decyl; cyclopentyl, cyclohexyl, cyclopentylmethyl, cyclopentylethyl, cyclopentylbutyl, cyclohexylmethyl, cyclohexylethyl, cyclohexylbutyl, norbornyl, tricyclo[5.2.1.0 2,6 ] Cyclic saturated hydrocarbon groups having 3 to 40 carbon atoms, such as decyl, adamantyl, and adamantylmethyl; alkenyl groups having 2 to 40 carbon atoms, such as vinyl, allyl, propenyl, butenyl, and hexenyl; cyclic unsaturated aliphatic hydrocarbon groups having 3 to 40 carbon atoms, such as cyclohexenyl; aryl groups having 6 to 40 carbon atoms, such as phenyl, naphthyl, alkylphenyl (2-methylphenyl, 3-methylphenyl, 4-methylphenyl, 4-ethylphenyl, 4-tert-butylphenyl, 4-n-butylphenyl, etc.), dialkylphenyl (2,4-dimethylphenyl, 2,4,6-triisopropylphenyl, etc.), alkylnaphthyl (methylnaphthyl, ethylnaphthyl, etc.), dialkylnaphthyl (dimethylnaphthyl, diethylnaphthyl, etc.); aralkyl groups having 7 to 40 carbon atoms, such as benzyl, 1-phenylethyl, and 2-phenylethyl, etc.

[0251] In addition, a part or all of the hydrogen atoms of the aforementioned hydrocarbon group may be optionally substituted by a group containing a hetero atom such as an oxygen atom, a sulfur atom, a nitrogen atom, or a halogen atom, and a part of the aforementioned hydrocarbon group -CH2- may be optionally replaced by a group containing a hetero atom such as an oxygen atom, a sulfur atom, or a nitrogen atom, and as a result, a hydroxyl group, a cyano group, a carbonyl group, an ether bond, an ester bond, a sulfonate bond, a carbonate bond, a lactone ring, a sultone ring, a carboxylic anhydride (-C(=O)-OC(=O)-), a haloalkyl group, etc. may be optionally contained. Examples of the hydrocarbon group containing a heteroatom include heteroaryl groups such as thienyl; alkoxyphenyl groups such as 4-hydroxyphenyl, 4-methoxyphenyl, 3-methoxyphenyl, 2-methoxyphenyl, 4-ethoxyphenyl, 4-tert-butoxyphenyl, and 3-tert-butoxyphenyl; alkoxynaphthyl groups such as methoxynaphthyl, ethoxynaphthyl, n-propoxynaphthyl, and n-butoxynaphthyl; dialkoxynaphthyl groups such as dimethoxynaphthyl and diethoxynaphthyl; aryloxyalkyl groups such as 2-aryl-2-oxoethyl groups such as 2-phenyl-2-oxoethyl, 2-(1-naphthyl)-2-oxoethyl, and 2-(2-naphthyl)-2-oxoethyl; and the like.

[0252] In formula (4-2), R 502 is a hydrocarbon group having 1 to 40 carbon atoms which may contain a hetero atom. 502 The hydrocarbon group shown in FIG. 1 may be exemplified as R 501 In addition, as other specific examples, fluoroalkyl groups such as trifluoromethyl, trifluoroethyl, 2,2,2-trifluoro-1-methyl-1-hydroxyethyl, 2,2,2-trifluoro-1-(trifluoromethyl)-1-hydroxyethyl; fluorinated aryl groups such as pentafluorophenyl and 4-trifluoromethylphenyl can also be listed.

[0253] In formula (4-3), R 503 It is a saturated hydrocarbon group having 1 to 8 carbon atoms and having at least 3 fluorine atoms, or an aryl group having 6 to 10 carbon atoms and having at least 3 fluorine atoms, and may contain a nitro group.

[0254] In formulas (4-1), (4-2) and (4-3), Mq + It is an onium cation. As the onium cation, a sulfonium cation, an iodonium cation or an ammonium cation is preferred, and a sulfonium cation is more preferred. As the sulfonium cation, the sulfonium cation described in Japanese Patent Application Laid-Open No. 2017-219836 can be cited.

[0255] As the quencher, a sulfonium salt of a carboxylic acid containing an iodinated benzene ring represented by the following formula (4-4) can also be preferably used.

[0256]

[0257] In formula (4-4), R 511 is a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an amino group, a nitro group, a cyano group; or a saturated hydrocarbon group having 1 to 6 carbon atoms, a saturated hydrocarbonoxy group having 1 to 6 carbon atoms, a saturated hydrocarboncarbonyloxy group having 2 to 6 carbon atoms, or a saturated hydrocarbonsulfonyloxy group having 1 to 4 carbon atoms, in which a part or all of the hydrogen atoms are optionally substituted with halogen atoms; or -N(R 511A )-C(=O)-R 511B or -N(R 511A )-C(=O)-OR 511B . R 511A R is a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms. 511B It is a saturated hydrocarbon group having 1 to 6 carbon atoms or an unsaturated aliphatic hydrocarbon group having 2 to 8 carbon atoms.

[0258] In formula (4-4), x' is an integer of 1 to 5. y' is an integer of 0 to 3. z' is an integer of 1 to 3. L 11is a single bond or a (z'+1)-valent linking group having 1 to 20 carbon atoms, and optionally contains at least one selected from an ether bond, a carbonyl group, an ester bond, an amide bond, a sultone ring, a lactam ring, a carbonate bond, a halogen atom, a hydroxyl group, and a carboxyl group. The saturated hydrocarbon group, saturated hydrocarbon oxy group, saturated hydrocarbon carbonyloxy group, and saturated hydrocarbon sulfonyloxy group may be any of a linear, branched, or cyclic group. When y' and / or z' is 2 or more, each R 511 They are optionally the same as or different from each other.

[0259] In formula (4-4), R 512 , R 513 and R 514 Each independently represents a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms and optionally containing a heteroatom. The hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include the same as those used as R in the description of formulas (M-1) and (M-2): 2 ~R 6 The hydrocarbon groups shown are the same groups as those exemplified.

[0260] Specific examples of the compound represented by formula (4-4) include those described in JP-A-2017-219836 and JP-A-2021-91666.

[0261] As another example of the quencher, there can be cited the polymer quencher described in Japanese Patent Publication No. 2008-239918. The polymer quencher improves the rectangularity of the resist pattern by being oriented along the surface of the resist film. The polymer quencher also has the effect of preventing the film loss of the pattern when applying the protective film for immersion exposure and the chamfering (rounding) of the top of the pattern.

[0262] Furthermore, betaine-type sulfonium salts described in Japanese Patent Nos. 6848776 and 2020-37544, methylated acids containing no fluorine atoms described in 2020-55797, sulfonium salts of sulfonamides described in 5807552, and sulfonium salts of sulfonamides containing iodine atoms described in 2019-211751 can also be used as quenchers.

[0263] When the resist material of the present invention contains the quencher, the content thereof is preferably 0 to 5 parts by mass, more preferably 0 to 4 parts by mass, based on 100 parts by mass of the base polymer. The quencher may be used alone or in combination of two or more.

[0264] [Other ingredients]

[0265] The resist material of the present invention may contain a surfactant, a dissolution inhibitor, a water repellency improver, acetylene alcohols, and the like in addition to the above-mentioned components.

[0266] As the above-mentioned surfactant, the surfactant described in paragraphs

[0165] to

[0166] of Japanese Patent Publication No. 2008-111103 can be cited. By adding a surfactant, the coating property of the anti-corrosion material can be further improved or controlled. When the anti-corrosion material of the present invention contains the above-mentioned surfactant, its content is preferably 0.0001 to 10 parts by mass relative to 100 parts by mass of the base polymer. The above-mentioned surfactant can be used alone or in combination of two or more.

[0267] When the resist material of the present invention is positive type, by mixing a dissolution inhibitor, the difference in dissolution rate between the exposed part and the unexposed part can be further increased, and the resolution can be further improved. As the above-mentioned dissolution inhibitor, there can be listed: a compound having a molecular weight of preferably 100 to 1000, more preferably 150 to 800, and containing two or more phenolic hydroxyl groups in the molecule, wherein the hydrogen atoms of the phenolic hydroxyl group are replaced by an acid-labile group at a ratio of 0 to 100 mol% as a whole, or a compound containing a carboxyl group in the molecule, wherein the hydrogen atoms of the carboxyl group are replaced by an acid-labile group at a ratio of 50 to 100 mol% as a whole. Specifically, there can be listed compounds in which the hydrogen atoms of the hydroxyl group and the carboxyl group of bisphenol A, trisphenol, phenolphthalein, cresol novolac, naphthalenecarboxylic acid, adamantanecarboxylic acid, and bile acid are replaced by acid-labile groups, for example, as described in paragraphs

[0155] to

[0178] of Japanese Patent Publication No. 2008-122932.

[0268] When the resist material of the present invention is positive type and contains the dissolution inhibitor, the content thereof is preferably 0 to 50 parts by mass, more preferably 5 to 40 parts by mass, based on 100 parts by mass of the base polymer. The dissolution inhibitor may be used alone or in combination of two or more.

[0269] The aforementioned water repellency improver can improve the water repellency of the surface of the resist film and can be used for immersion photolithography without topcoating. As the aforementioned water repellency improver, preferably a polymer containing a fluoroalkyl group, a polymer containing a 1,1,1,3,3,3-hexafluoro-2-propanol residue of a specific structure, etc., more preferably a substance exemplified in Japanese Patent Publication No. 2007-297590, Japanese Patent Publication No. 2008-111103, etc. The aforementioned water repellency improver needs to be dissolved in an alkaline developer or an organic solvent developer. The aforementioned specific water repellency improver having a 1,1,1,3,3,3-hexafluoro-2-propanol residue has good solubility in a developer. As a water repellency improver, a polymer containing a repeating unit containing an amino group or an amine salt has a high effect of preventing acid evaporation in PEB and preventing poor opening of the hole pattern after development. When the resist material of the present invention contains the water repellency improver, the content thereof is preferably 0 to 20 parts by mass, more preferably 0.5 to 10 parts by mass, based on 100 parts by mass of the base polymer. The water repellency improver may be used alone or in combination of two or more.

[0270] Examples of the acetylene alcohols include those described in paragraphs

[0179] to

[0182] of Japanese Patent Application Laid-Open No. 2008-122932. When the anti-corrosion material of the present invention contains acetylene alcohols, the content thereof is preferably 0 to 5 parts by mass relative to 100 parts by mass of the base polymer. The acetylene alcohols may be used alone or in combination of two or more.

[0271] The anti-corrosion material of the present invention can be prepared by fully mixing the aforementioned components, adjusting the sensitivity and film thickness in a prescribed range, and filtering the resulting solution. The filtering process is important for reducing the defects of the anti-corrosion pattern after development. The caliber of the membrane used for filtering is preferably less than 1 μm, more preferably less than 10 nm, and more preferably less than 5 nm. The smaller the caliber, the more it can suppress the generation of defects in the fine pattern. As the raw materials of the membrane, tetrafluoroethylene, polyethylene, polypropylene, nylon, polyurethane, polycarbonate, polyimide, polyamide-imide, polysulfone, etc. can be listed. It is also possible to use a membrane whose surface of tetrafluoroethylene, polyethylene, polypropylene, etc. is modified to improve the adsorption capacity. Tetrafluoroethylene, polyethylene and polypropylene do not have polarity, so they do not have the adsorption capacity of gel and metal ions due to polarity like the membranes of nylon, polyurethane, polycarbonate, polyimide, etc., but by surface modification based on polar functional groups, the adsorption capacity of gel and metal ions can be improved. In particular, by modifying the surface of polyethylene or polypropylene films that can form films with smaller pore sizes, it is possible to reduce not only fine particles but also polar particles and metal ions. It is possible to use films made of different materials stacked together or films made of films with different pore sizes stacked together.

[0272] A membrane having an ion exchange capability may also be used. In the case of an ion exchange membrane that adsorbs cations, metal impurities can be reduced by adsorbing metal ions.

[0273] When filtering, multiple filters may be connected. The types and calibers of the membranes of the multiple filters may be the same or different. Filtering may be performed in a pipe connecting multiple containers, or an outlet and an inlet may be provided for one container and the pipes may be connected for circulation filtration. The filters for filtering may be connected by serial pipes or by parallel pipes.

[0274] [Pattern Formation Method]

[0275] When the resist material of the present invention is used to manufacture various integrated circuits, known photolithography techniques can be applied. For example, as a pattern forming method, a method including the following steps can be cited: a step of forming a resist film on a substrate using the resist material; a step of exposing the resist film using high-energy rays; and a step of developing the exposed resist film using a developer.

[0276] First, the anti-corrosion material of the present invention is applied to a substrate for integrated circuit manufacturing (Si, SiO2, SiN, SiON, TiN, WSi, BPSG, SOG, organic anti-reflection film, etc.) or a substrate for mask circuit manufacturing (Cr, CrO, CrON, CrN, MoSi2, SiO2, MoSi2 laminated film, Ta, TaN, TaCN, Ru, Nb, Mo, Mn, Co, Ni or their alloys, etc.) by a suitable coating method such as spin coating, roller coating, flow coating, dip coating, spray coating, scraping coating, etc., so that the coating film thickness becomes 0.01 to 2 μm. It is preferably pre-baked at 60 to 150° C. for 10 seconds to 30 minutes, more preferably at 80 to 120° C. for 30 seconds to 20 minutes on a hot plate to form an anti-corrosion film.

[0277] Next, the resist film is exposed using high-energy radiation. Examples of the high-energy radiation include ultraviolet rays, far ultraviolet rays, EB, EUV with a wavelength of 3 to 15 nm, X-rays, soft X-rays, excimer lasers, gamma rays, synchrotron radiation, etc. When ultraviolet rays, far ultraviolet rays, EUV, X-rays, soft X-rays, excimer lasers, gamma rays, synchrotron radiation, etc. are used as the high-energy radiation, the exposure is preferably 1 to 200 mJ / cm directly or using a mask for forming a target pattern. 2 More preferably, it is 10 to 100 mJ / cm 2 When EB is used as high energy radiation, the exposure dose is preferably 0.1 to 300 μC / cm 2More preferably, 0.5 to 200 μC / cm 2 It should be noted that the resist material of the present invention is particularly suitable for fine patterning based on KrF excimer laser, ArF excimer laser, EB, EUV, X-ray, soft X-ray, gamma ray, synchrotron radiation among high-energy rays, and is particularly suitable for fine patterning based on EB or EUV.

[0278] After the exposure, PEB is preferably performed on a hot plate or in an oven at 30 to 150° C. for 10 seconds to 30 minutes, more preferably at 50 to 120° C. for 30 seconds to 20 minutes, but it is not necessarily performed.

[0279] After exposure or PEB, a developer of an alkaline aqueous solution of 0.1 to 10% by mass, preferably 2 to 5% by mass, such as tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), tetrapropylammonium hydroxide (TPAH), tetrabutylammonium hydroxide (TBAH), etc. is used to develop the exposed resist film for 3 seconds to 3 minutes, preferably 5 seconds to 2 minutes, by conventional methods such as a dip method, a puddle method, and a spray method, thereby forming a target pattern. In the case of a positive resist material, the portion irradiated with light is dissolved in the developer, and the portion not exposed is not dissolved, thereby forming a positive pattern as the target on the substrate. In the case of a negative resist material, in contrast to the case of a positive resist material, the portion irradiated with light is not dissolved in the developer, and the portion not exposed is dissolved.

[0280] A negative pattern can also be obtained by developing with an organic solvent using a positive resist material containing a base polymer having an acid-labile group. Examples of the developer used at this time include 2-octanone, 2-nonanone, 2-heptanone, 3-heptanone, 4-heptanone, 2-hexanone, 3-hexanone, diisobutyl ketone, methylcyclohexanone, acetophenone, methylacetophenone, propyl acetate, butyl acetate, isobutyl acetate, amyl acetate, butyl acetate, isoamyl acetate, propyl formate, butyl formate, isobutyl formate, amyl formate, isoamyl formate, methyl valerate, methyl pentenoate, methyl crotonate, and crotonic acid. ethyl ester, methyl propionate, ethyl propionate, ethyl 3-ethoxypropionate, methyl lactate, ethyl lactate, propyl lactate, butyl lactate, isobutyl lactate, amyl lactate, isoamyl lactate, methyl 2-hydroxyisobutyrate, ethyl 2-hydroxyisobutyrate, methyl benzoate, ethyl benzoate, phenyl acetate, benzyl acetate, methyl phenylacetate, benzyl formate, phenylethyl formate, methyl 3-phenylpropionate, benzyl propionate, ethyl phenylacetate, 2-phenylethyl acetate, etc. These organic solvents may be used alone or in combination of two or more.

[0281] At the end of the development, rinsing is performed. As the rinsing solution, a solvent that is miscible with the developer and does not dissolve the resist film is preferred. As such a solvent, alcohols having 3 to 10 carbon atoms, ether compounds having 8 to 12 carbon atoms, alkanes, alkenes, alkynes, and aromatic solvents having 6 to 12 carbon atoms are preferably used.

[0282] Examples of the alcohol having 3 to 10 carbon atoms include n-propanol, isopropanol, 1-butanol, 2-butanol, isobutanol, tert-butanol, 1-pentanol, 2-pentanol, 3-pentanol, tert-pentanol, neopentyl alcohol, 2-methyl-1-butanol, 3-methyl-1-butanol, 3-methyl-3-pentanol, cyclopentanol, 1-hexanol, 2-hexanol, 3-hexanol, 2,3-dimethyl-2-butanol, 3,3-dimethyl-1-butanol, 3,3-dimethyl-2-butanol, 2-ethyl-1-butanol, 2-methyl-1-pentanol, 2-methyl-2-pentanol, 2-methyl-3-pentanol, 3-methyl-1-pentanol, 3-methyl-2-pentanol, 3-methyl-3-pentanol, 4-methyl-1-pentanol, 4-methyl-2-pentanol, 4-methyl-3-pentanol, cyclohexanol, and 1-octanol.

[0283] Examples of the ether compound having 8 to 12 carbon atoms include di-n-butyl ether, diisobutyl ether, di-sec-butyl ether, di-n-amyl ether, diisoamyl ether, di-sec-amyl ether, di-tert-amyl ether, and di-n-hexyl ether.

[0284] Examples of the aforementioned alkanes having 6 to 12 carbon atoms include hexane, heptane, octane, nonane, decane, undecane, dodecane, methylcyclopentane, dimethylcyclopentane, cyclohexane, methylcyclohexane, dimethylcyclohexane, cycloheptane, cyclooctane, and cyclononane. Examples of the aforementioned alkenes having 6 to 12 carbon atoms include hexene, heptene, octene, cyclohexene, methylcyclohexene, dimethylcyclohexene, cycloheptene, and cyclooctene. Examples of the aforementioned alkynes having 6 to 12 carbon atoms include hexyne, heptyne, and octyne.

[0285] Examples of the aromatic solvent include toluene, xylene, ethylbenzene, cumene, tert-butylbenzene, and mesitylene.

[0286] By performing rinsing, the occurrence of collapse and defects of the resist pattern can be reduced. In addition, rinsing is not necessarily required, and the amount of solvent used can be reduced by not performing rinsing.

[0287] The hole pattern and groove pattern after development can also be shrunk by heat flow, RELACS technology or DSA technology. A shrinking agent is applied to the hole pattern, and the shrinking agent is cross-linked on the surface of the resist film by diffusion of the acid catalyst from the resist film during baking, and the shrinking agent adheres to the side wall of the hole pattern. The baking temperature is preferably 70 to 180°C, more preferably 80 to 170°C, and the baking time is preferably 10 to 300 seconds, and the excess shrinking agent is removed to shrink the hole pattern.

[0288] Example

[0289] Hereinafter, the present invention will be specifically described with reference to synthesis examples, examples and comparative examples, but the present invention is not limited to the following examples.

[0290] The monomers PM-1 to PM-18, cPM-1, cPM-2, AM-1 to AM-7 and FM-1 used for synthesizing the base polymer are shown below. PM-1 to PM-14 were synthesized by ion exchange of ammonium salt of fluorinated benzenesulfonic acid providing the following anions and sulfonium chloride providing the following cations. In addition, the Mw of the polymer is a polystyrene conversion measurement value based on GPC using THF as a solvent.

[0291]

[0292]

[0293]

[0294]

[0295] [Synthesis Example 1] Synthesis of Polymer P-1

[0296] To a 2L flask, add 8.4g of 1-methyl-1-cyclopentyl methacrylate, 4.8g of 4-hydroxystyrene, 8.8g of PM-1, and 40g of THF as a solvent. The reaction vessel was cooled to -70°C under a nitrogen atmosphere, and the reduced pressure degassing and nitrogen blowing were repeated 3 times. After warming to room temperature, 1.2g of AIBN was added as a polymerization initiator, and the temperature was raised to 60°C and reacted for 15 hours. The reaction solution was added to 1L of isopropanol, and the precipitated white solid was filtered out. The obtained white solid was dried under reduced pressure at 60°C to obtain polymer P-1. The composition of polymer P-1 is determined by 13 C-NMR and 1 The molecular weight was confirmed by H-NMR, and the Mw and Mw / Mn were confirmed by GPC.

[0297]

[0298] [Synthesis Example 2] Synthesis of Polymer P-2

[0299] To a 2L flask, add 9.0 g of 1-vinyl-1-cyclopentyl methacrylate, 4.8 g of 3-hydroxystyrene, 8.6 g of PM-2, and 40 g of THF as a solvent. The reaction vessel was cooled to -70°C under a nitrogen atmosphere, and the reduced pressure degassing and nitrogen blowing were repeated 3 times. After warming to room temperature, 1.2 g of AIBN was added as a polymerization initiator, and the temperature was raised to 60°C and reacted for 15 hours. The reaction solution was added to 1L of isopropanol, and the precipitated white solid was filtered out. The obtained white solid was dried under reduced pressure at 60°C to obtain polymer P-2. The composition of polymer P-2 is determined by 13 C-NMR and 1 The molecular weight was confirmed by H-NMR, and the Mw and Mw / Mn were confirmed by GPC.

[0300]

[0301] [Synthesis Example 3] Synthesis of Polymer P-3

[0302] To a 2L flask, add 11.1g of AM-1, 4.8g of 3-hydroxystyrene, 11.6g of PM-3, and 40g of THF as a solvent. The reaction vessel was cooled to -70°C under a nitrogen atmosphere, and the reduced pressure degassing and nitrogen blowing were repeated 3 times. After warming to room temperature, 1.2g of AIBN as a polymerization initiator was added, and the temperature was raised to 60°C and reacted for 15 hours. The reaction solution was added to 1L of isopropanol, and the precipitated white solid was filtered out. The obtained white solid was dried under reduced pressure at 60°C to obtain polymer P-3. The composition of polymer P-3 is determined by 13 C-NMR and 1 The molecular weight was confirmed by H-NMR, and the Mw and Mw / Mn were confirmed by GPC.

[0303]

[0304] [Synthesis Example 4] Synthesis of Polymer P-4

[0305] To a 2L flask, add 8.1g of AM-2, 2.7g of AM-4, 4.8g of 3-hydroxystyrene, 10.1g of PM-4 and 40g of THF as a solvent. Cool the reaction vessel to -70°C under a nitrogen atmosphere, and repeat the reduced pressure degassing and nitrogen blowing 3 times. After warming to room temperature, add 1.2g of AIBN as a polymerization initiator, heat to 60°C and react for 15 hours. Add the reaction solution to 1L of isopropanol, and filter out the precipitated white solid. The obtained white solid is dried under reduced pressure at 60°C to obtain polymer P-4. The composition of polymer P-4 is determined by 13 C-NMR and 1The molecular weight was confirmed by H-NMR, and the Mw and Mw / Mn were confirmed by GPC.

[0306]

[0307] [Synthesis Example 5] Synthesis of Polymer P-5

[0308] To a 2L flask, add 11.6g of AM-3, 5.2g of 3-hydroxystyrene, 8.3g of PM-5, and 40g of THF as a solvent. The reaction vessel was cooled to -70°C under a nitrogen atmosphere, and the reduced pressure degassing and nitrogen blowing were repeated 3 times. After warming to room temperature, 1.2g of AIBN as a polymerization initiator was added, and the temperature was raised to 60°C and reacted for 15 hours. The reaction solution was added to 1L of isopropanol, and the precipitated white solid was filtered out. The obtained white solid was dried under reduced pressure at 60°C to obtain polymer P-5. The composition of polymer P-5 is determined by 13 C-NMR and 1 The molecular weight was confirmed by H-NMR, and the Mw and Mw / Mn were confirmed by GPC.

[0309]

[0310] [Synthesis Example 6] Synthesis of Polymer P-6

[0311] To a 2L flask, add 8.3g of AM-5, 4.8g of 3-hydroxystyrene, 8.2g of PM-6 and 40g of THF as a solvent. The reaction vessel was cooled to -70°C under a nitrogen atmosphere, and the reduced pressure degassing and nitrogen blowing were repeated 3 times. After warming to room temperature, 1.2g of AIBN was added as a polymerization initiator, and the temperature was raised to 60°C and reacted for 15 hours. The reaction solution was added to 1L of isopropanol, and the precipitated white solid was filtered out. The obtained white solid was dried under reduced pressure at 60°C to obtain polymer P-6. The composition of polymer P-6 is determined by 13 C-NMR and 1 The molecular weight was confirmed by H-NMR, and the Mw and Mw / Mn were confirmed by GPC.

[0312]

[0313] [Synthesis Example 7] Synthesis of Polymer P-7

[0314] To a 2L flask, add 11.1g of AM-1, 3.4g of 3-hydroxystyrene, 3.2g of monomer FM-1, 10.7g of PM-7 and 40g of THF as a solvent. The reaction vessel was cooled to -70°C under a nitrogen atmosphere, and the reduced pressure degassing and nitrogen blowing were repeated 3 times. After warming to room temperature, 1.2g of AIBN as a polymerization initiator was added, and the temperature was raised to 60°C and reacted for 15 hours. The reaction solution was added to 1L of isopropanol, and the precipitated white solid was filtered out. The obtained white solid was dried under reduced pressure at 60°C to obtain polymer P-7. The composition of polymer P-7 is determined by 13 C-NMR and 1 The molecular weight was confirmed by H-NMR, and the Mw and Mw / Mn were confirmed by GPC.

[0315]

[0316] [Synthesis Example 8] Synthesis of Polymer P-8

[0317] To a 2L flask, add 11.1g of AM-1, 4.8g of 3-hydroxystyrene, 9.1g of PM-8, and 40g of THF as a solvent. Cool the reaction vessel to -70°C under a nitrogen atmosphere, and repeat the reduced pressure degassing and nitrogen blowing 3 times. After warming to room temperature, add 1.2g of AIBN as a polymerization initiator, heat to 60°C and react for 15 hours. Add the reaction solution to 1L of isopropanol, and filter out the precipitated white solid. The obtained white solid is dried under reduced pressure at 60°C to obtain polymer P-8. The composition of polymer P-8 is determined by 13 C-NMR and 1 The molecular weight was confirmed by H-NMR, and the Mw and Mw / Mn were confirmed by GPC.

[0318]

[0319] [Synthesis Example 9] Synthesis of Polymer P-9

[0320] To a 2L flask, add 12.1g of AM-6, 4.8g of 4-hydroxystyrene, 9.2g of PM-9 and 40g of THF as a solvent. Cool the reaction vessel to -70°C under a nitrogen atmosphere, and repeat the reduced pressure degassing and nitrogen blowing 3 times. After warming to room temperature, add 1.2g of AIBN as a polymerization initiator, heat to 60°C and react for 15 hours. Add the reaction solution to 1L of isopropanol, and filter out the precipitated white solid. The obtained white solid is dried under reduced pressure at 60°C to obtain polymer P-9. The composition of polymer P-9 is determined by 13 C-NMR and 1 The molecular weight was confirmed by H-NMR, and the Mw and Mw / Mn were confirmed by GPC.

[0321]

[0322] [Synthesis Example 10] Synthesis of Polymer P-10

[0323] To a 2L flask, add 12.0g of AM-7, 4.8g of 4-hydroxystyrene, 8.9g of PM-10 and 40g of THF as a solvent. The reaction vessel was cooled to -70°C under a nitrogen atmosphere, and the reduced pressure degassing and nitrogen blowing were repeated 3 times. After warming to room temperature, 1.2g of AIBN was added as a polymerization initiator, and the temperature was raised to 60°C and reacted for 15 hours. The reaction solution was added to 1L of isopropanol, and the precipitated white solid was filtered out. The obtained white solid was dried under reduced pressure at 60°C to obtain polymer P-10. The composition of polymer P-10 is determined by 13 C-NMR and 1 The molecular weight was confirmed by H-NMR, and the Mw and Mw / Mn were confirmed by GPC.

[0324]

[0325] [Synthesis Example 11] Synthesis of Polymer P-11

[0326] To a 2L flask, add 11.1g of AM-1, 4.8g of 3-hydroxystyrene, 7.7g of PM-11, and 40g of THF as a solvent. The reaction vessel was cooled to -70°C under a nitrogen atmosphere, and the reduced pressure degassing and nitrogen blowing were repeated 3 times. After warming to room temperature, 1.2g of AIBN was added as a polymerization initiator, and the temperature was raised to 60°C and reacted for 15 hours. The reaction solution was added to 1L of isopropanol, and the precipitated white solid was filtered out. The obtained white solid was dried under reduced pressure at 60°C to obtain polymer P-11. The composition of polymer P-11 is determined by 13 C-NMR and 1 The molecular weight was confirmed by H-NMR, and the Mw and Mw / Mn were confirmed by GPC.

[0327]

[0328] [Synthesis Example 12] Synthesis of Polymer P-12

[0329] To a 2L flask, add 11.1g of AM-1, 4.8g of 3-hydroxystyrene, 11.1g of PM-12, and 40g of THF as a solvent. Cool the reaction vessel to -70°C under a nitrogen atmosphere, and repeat the reduced pressure degassing and nitrogen blowing three times. After warming to room temperature, add 1.2g of AIBN as a polymerization initiator, heat to 60°C and react for 15 hours. Add the reaction solution to 1L of isopropanol, and filter out the precipitated white solid. The obtained white solid is dried under reduced pressure at 60°C to obtain polymer P-12. The composition of polymer P-12 is determined by 13 C-NMR and 1 The molecular weight was confirmed by H-NMR, and the Mw and Mw / Mn were confirmed by GPC.

[0330]

[0331] [Synthesis Example 13] Synthesis of Polymer P-13

[0332] To a 2L flask, add 11.1g of AM-1, 4.8g of 3-hydroxystyrene, 12.0g of PM-13 and 40g of THF as a solvent. The reaction vessel was cooled to -70°C under a nitrogen atmosphere, and the reduced pressure degassing and nitrogen blowing were repeated 3 times. After warming to room temperature, 1.2g of AIBN was added as a polymerization initiator, and the temperature was raised to 60°C and reacted for 15 hours. The reaction solution was added to 1L of isopropanol, and the precipitated white solid was filtered out. The obtained white solid was dried under reduced pressure at 60°C to obtain polymer P-13. The composition of polymer P-13 is determined by 13 C-NMR and 1 The molecular weight was confirmed by H-NMR, and the Mw and Mw / Mn were confirmed by GPC.

[0333]

[0334] [Synthesis Example 14] Synthesis of Polymer P-14

[0335] To a 2L flask, add 11.1g of AM-1, 4.8g of 3-hydroxystyrene, 11.9g of PM-14, and 40g of THF as a solvent. Cool the reaction vessel to -70°C under a nitrogen atmosphere, and repeat the reduced pressure degassing and nitrogen blowing three times. After warming to room temperature, add 1.2g of AIBN as a polymerization initiator, heat to 60°C and react for 15 hours. Add the reaction solution to 1L of isopropanol, and filter out the precipitated white solid. The obtained white solid is dried under reduced pressure at 60°C to obtain polymer P-14. The composition of polymer P-14 is determined by 13 C-NMR and 1 The molecular weight was confirmed by H-NMR, and the Mw and Mw / Mn were confirmed by GPC.

[0336]

[0337] [Synthesis Example 15] Synthesis of Polymer P-15

[0338] To a 2L flask, add 11.1g of AM-1, 4.8g of 3-hydroxystyrene, 10.8g of PM-15, and 40g of THF as a solvent. Cool the reaction vessel to -70°C under a nitrogen atmosphere, and repeat the reduced pressure degassing and nitrogen blowing three times. After warming to room temperature, add 1.2g of AIBN as a polymerization initiator, heat to 60°C and react for 15 hours. Add the reaction solution to 1L of isopropanol, and filter out the precipitated white solid. The obtained white solid is dried under reduced pressure at 60°C to obtain polymer P-15. The composition of polymer P-15 is determined by 13 C-NMR and 1 The molecular weight was confirmed by H-NMR, and the Mw and Mw / Mn were confirmed by GPC.

[0339]

[0340] [Synthesis Example 16] Synthesis of Polymer P-16

[0341] To a 2L flask, add 11.1g of AM-1, 4.8g of 3-hydroxystyrene, 11.4g of PM-16, and 40g of THF as a solvent. The reaction vessel was cooled to -70°C under a nitrogen atmosphere, and the reduced pressure degassing and nitrogen blowing were repeated 3 times. After warming to room temperature, 1.2g of AIBN was added as a polymerization initiator, and the temperature was raised to 60°C and reacted for 15 hours. The reaction solution was added to 1L of isopropanol, and the precipitated white solid was filtered out. The obtained white solid was dried under reduced pressure at 60°C to obtain polymer P-16. The composition of polymer P-16 is determined by 13 C-NMR and 1 The molecular weight was confirmed by H-NMR, and the Mw and Mw / Mn were confirmed by GPC.

[0342]

[0343] [Synthesis Example 17] Synthesis of Polymer P-17

[0344] To a 2L flask, add 11.1g of AM-1, 4.8g of 3-hydroxystyrene, 11.0g of PM-17, and 40g of THF as a solvent. The reaction vessel was cooled to -70°C under a nitrogen atmosphere, and the reduced pressure degassing and nitrogen blowing were repeated 3 times. After warming to room temperature, 1.2g of AIBN as a polymerization initiator was added, and the temperature was raised to 60°C and reacted for 15 hours. The reaction solution was added to 1L of isopropanol, and the precipitated white solid was filtered out. The obtained white solid was dried under reduced pressure at 60°C to obtain polymer P-17. The composition of polymer P-17 is determined by 13 C-NMR and 1 The molecular weight was confirmed by H-NMR, and the Mw and Mw / Mn were confirmed by GPC.

[0345]

[0346] [Synthesis Example 18] Synthesis of Polymer P-18

[0347] To a 2L flask, add 11.1g of AM-1, 4.8g of 3-hydroxystyrene, 10.1g of PM-18, and 40g of THF as a solvent. Cool the reaction vessel to -70°C under a nitrogen atmosphere, and repeat the reduced pressure degassing and nitrogen blowing three times. After warming to room temperature, add 1.2g of AIBN as a polymerization initiator, heat to 60°C and react for 15 hours. Add the reaction solution to 1L of isopropanol, and filter out the precipitated white solid. The obtained white solid is dried under reduced pressure at 60°C to obtain polymer P-18. The composition of polymer P-18 is determined by 13 C-NMR and 1 The molecular weight was confirmed by H-NMR, and the Mw and Mw / Mn were confirmed by GPC.

[0348]

[0349] [Comparative Synthesis Example 1] Synthesis of Comparative Polymer cP-1

[0350] A comparative polymer cP-1 was synthesized by the same method as in Synthesis Example 1 except that PM-1 was changed to cPM-1.

[0351]

[0352] [Comparative Synthesis Example 2] Synthesis of Comparative Polymer cP-2

[0353] Comparative polymer cP-2 was synthesized by the same method as in Synthesis Example 1 except that PM-1 was changed to cPM-2.

[0354]

[0355] [Examples 1 to 21, Comparative Examples 1 and 2] Preparation and Evaluation of Anti-Corrosion Materials

[0356] (1) Preparation of anti-corrosion materials

[0357] A solution in which each component was dissolved in the composition shown in Table 1 was filtered using a filter having a size of 0.2 μm to prepare a resist material.

[0358] In Table 1, the components are as follows.

[0359] Organic solvent: PGMEA (propylene glycol monomethyl ether acetate)

[0360] EL(ethyl lactate)

[0361] DAA (Diacetone Alcohol)

[0362] Acid generator: PAG-1~PAG-3

[0363]

[0364] ·Quencher: Q-1~Q-6

[0365]

[0366] (2) EUV lithography evaluation

[0367] Each resist material shown in Table 1 was spin-coated on a Si substrate formed with a silicon-containing spin-coated hard mask SHB-A940 (silicon content of 43% by mass) manufactured by Shin-Etsu Chemical Co., Ltd. with a film thickness of 20 nm, and pre-baked at 105° C. for 60 seconds using a hot plate to prepare a resist film with a film thickness of 60 nm. The resist film was exposed using an EUV scanner NXE3400 manufactured by ASML (NA of 0.33, σ of 0.9 / 0.6, quadruple illumination, a mask with a hole pattern having a size of 40 nm on the wafer and a bias voltage of +20%), and PEB was performed for 60 seconds on a hot plate at the temperature described in Table 1, and developed for 30 seconds using a 2.38% by mass TMAH aqueous solution to form a hole pattern having a size of 20 nm.

[0368] The exposure amount when a hole with a size of 20 nm was formed was measured using a length measurement SEM (CG6300) manufactured by Hitachi High-Technologies Corporation, and this was taken as the sensitivity. In addition, the sizes of 50 holes at this time were measured, and the value (3σ) three times the standard deviation (σ) calculated from the results was taken as CDU. The results are shown in Table 1.

[0369] [Table 1]

[0370]

[0371] The results shown in Table 1 show that the resist material of the present invention including a base polymer containing repeating unit a composed of a substituted or unsubstituted arylsulfonic acid anion and an onium cation bonded to a polymer main chain having a group containing an iodine atom or a bromine atom has good CDU.

Claims

1. A resist material comprising a base polymer containing a repeating unit a, wherein the repeating unit a is formed of a substituted or unsubstituted arylsulfonic acid anion and an onium cation, wherein the substituted or unsubstituted arylsulfonic acid anion is bonded to a polymer main chain having a group containing an iodine atom or a bromine atom.

2. The anti-corrosion material according to claim 1, wherein The repeating unit a is represented by the following formula (a1) or (a2), Wherein, m is an integer from 0 to 5; R A is a hydrogen atom or a methyl group; R B is a hydrogen atom or optionally with X 1 Bond to form a ring; X 1 is a single bond, a phenylene ring, a naphthalene ring, an ester bond or an amide bond; X 2A is a divalent organic group having 1 to 24 carbon atoms and having at least one iodine atom or bromine atom, and optionally having at least one selected from an oxygen atom, a nitrogen atom and a sulfur atom; X 2B is a monovalent organic group having 1 to 10 carbon atoms and having at least one iodine atom or bromine atom, and optionally having at least one selected from an oxygen atom, a nitrogen atom and a sulfur atom; X 3 It is a single bond, an ether bond, an ester bond, a thioether bond or an alkane diyl group having 1 to 6 carbon atoms; X 4 is a trivalent organic group having 1 to 12 carbon atoms, optionally having at least one selected from an oxygen atom, a nitrogen atom and a sulfur atom; R is an (m+2)-valent aromatic hydrocarbon group having 6 to 10 carbon atoms; R 1 is a saturated hydrocarbon group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a fluorine atom, a trifluoromethoxy group, a difluoromethoxy group, a cyano group or a nitro group; M + It is a sulfonium cation or an iodonium cation.

3. The anti-corrosion material according to claim 1, wherein The base polymer further comprises a repeating unit represented by the following formula (b1) or a repeating unit represented by the following formula (b2), In the formula, R A are each independently a hydrogen atom or a methyl group; Y 1 is a single bond, a linking group having 1 to 12 carbon atoms and containing at least one selected from a phenylene group or a naphthylene group, or an ester bond, an ether bond, a lactone ring, a hydroxyl group, and a halogen atom; Y 2 is a single bond or an ester bond; Y 3 is a single bond, an ether bond or an ester bond; R 11 and R 12 are each independently an acid-labile group; R 13 is a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a trifluoromethyl group, a cyano group, a saturated hydrocarbon group having 1 to 6 carbon atoms, a saturated hydrocarbonoxy group having 1 to 6 carbon atoms, a saturated hydrocarboncarbonyl group having 2 to 7 carbon atoms, a saturated hydrocarboncarbonyloxy group having 2 to 7 carbon atoms, or a saturated hydrocarbonoxycarbonyl group having 2 to 7 carbon atoms; R 14 It is a single bond or an alkanediyl group having 1 to 6 carbon atoms, wherein a part of the -CH2- of the alkanediyl group is optionally replaced by an ether bond or an ester bond; a is 1 or 2, b is an integer from 0 to 4, wherein 1≤a+b≤5. The resist material according to claim 3 , which is a chemically amplified positive resist material. The resist material according to claim 1 , further comprising an organic solvent. The anti-corrosion material according to claim 1 , further comprising a surfactant.

7. A pattern forming method, comprising: A step of forming a resist film on a substrate using the resist material according to any one of claims 1 to 6; a step of exposing the resist film to high-energy radiation; and a step of developing the exposed resist film using a developer.

8. The pattern forming method according to claim 7, wherein: The high-energy rays are KrF excimer laser, ArF excimer laser, electron beam or extreme ultraviolet rays with a wavelength of 3 to 15 nm.

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