Resist materials and pattern formation methods

Abstract

This invention relates to resist materials and patterning methods. The objective of this invention is to provide a resist material with high sensitivity and improved LWR and CDU, and a patterning method using the same. The solution to this objective is a resist material comprising: a base polymer having a repeating unit a having a salt structure consisting of a sulfonic acid anion bonded to the polymer backbone and a sulfonium cation represented by the following formula (1).

Description

Technical Field

[0001] This invention relates to a resist material and a method for forming patterns. Background Technology

[0002] With the increasing integration and speed of LSI (Lithium-ion Sensors), the miniaturization of patterning is also progressing rapidly. This is because the high-speed communication of 5G and the widespread adoption of artificial intelligence (AI) necessitate high-performance devices to process them. Regarding the most advanced miniaturization technology, mass production of 5nm node devices using 13.5nm extreme ultraviolet (EUV) lithography is already underway. Furthermore, discussions are underway regarding the use of EUV lithography for next-generation 3nm and the next-next-generation 2nm node devices; Belgium's IMEC has already demonstrated the development of 1nm and 0.7nm devices.

[0003] As miniaturization progresses, image blurring caused by acid diffusion becomes a problem. To ensure the resolution of micropatterns smaller than 45 nm, it has been proposed that in addition to the previously advocated improvement in dissolution contrast, the control of acid diffusion is also important (Non-Patent Literature 1). However, since chemically amplified resist materials utilize acid diffusion to enhance sensitivity and contrast, if the post-exposure baking (PEB) temperature is lowered or the time is shortened to suppress acid diffusion to the limit, sensitivity and contrast will also be significantly reduced.

[0004] This illustrates the triangular trade-off between sensitivity, resolution, and edge roughness (LWR). To improve resolution, acid diffusion needs to be suppressed, but shortening the acid diffusion distance will reduce sensitivity.

[0005] Adding acid-generating agents that produce bulky acids is effective in suppressing acid diffusion. Therefore, it has been proposed to include repeating units from onium salts with polymerizable unsaturated bonds in the polymer. In this case, the polymer can also function as an acid-generating agent (polymer-bonded acid-generating agent). Patent Document 1 has proposed sulfonium salts and sulfonium salts with polymerizable unsaturated bonds that produce specific sulfonic acids. Patent Document 2 has proposed sulfonium salts in which sulfonic acids are directly bonded to the main chain.

[0006] To create finer patterns, it's necessary not only to suppress acid diffusion but also to improve solubility contrast. To improve solubility contrast, polarity-converting base polymers that produce phenolic and carboxyl groups through acid-induced deprotection reactions can be used. Resist materials containing these polymers are used, and positive patterns are formed using alkali development or negative patterns using organic solvent development, but the positive patterns exhibit high resolution. This is because alkali development provides higher solubility contrast. Furthermore, carboxyl-producing base polymers have higher alkali solubility than phenolic base polymers, resulting in higher solubility contrast. Therefore, carboxyl-producing base polymers are increasingly being used.

[0007] A non-chemically amplified resist material with a main chain decomposition capability, formed by copolymerizing α-chloroacrylate and α-methylstyrene as the base polymer (whose main chain decomposes upon exposure and whose solubility in organic solvent developers improves due to molecular weight reduction), exhibits low solubility contrast despite the absence of acid diffusion. In contrast, the aforementioned chemically amplified resist material with polarity-changing properties offers high resolution.

[0008] Some have proposed adding an acid-generating agent with polarity-changing properties, in addition to a base polymer with polarity-changing capabilities, to further improve the solubility contrast. Patent documents 3 and 4 disclose resist materials containing sulfonate salts with tertiary ester-type acid-instable groups in the cationic moiety, and patent document 5 discloses resist materials containing polymers with sulfonic acid anions bonded to the polymer backbone and sulfonate cations with acid-instable groups. However, the improvement in solubility contrast and reduction in swelling are insufficient in the alicyclic structure and carbinol-type acid-instable groups described in these documents.

[0009] Existing technical documents

[0010] Patent documents

[0011] [Patent Document 1] Japanese Patent Application Publication No. 2006-045311

[0012] [Patent Document 2] Japanese Patent Application Publication No. 2006-178317

[0013] [Patent Document 3] Japanese Patent Application Publication No. 2011-006400

[0014] [Patent Document 4] Japanese Patent Application Publication No. 2021-070692

[0015] [Patent Document 5] Japanese Patent Application Publication No. 2014-224236

[0016] Non-patent literature

[0017] [Non-Patent Literature 1] SPIE Vol.6520 65203L-1(2007) Summary of the Invention

[0018] [The problem that the invention aims to solve]

[0019] The goal is to develop an acid-generating agent in resist materials that can improve the light-reflection ratio (LWR) of line patterns, the dimensional uniformity (CDU) of hole patterns, and also enhance sensitivity. Therefore, a significant improvement in dissolution contrast during development is required.

[0020] The present invention was made in view of the foregoing circumstances, and aims to provide a resist material, particularly in positive resist materials, that is highly sensitive and improves LWR and CDU, and a method for patterning using the resist material.

[0021] [Methods for solving the problem]

[0022] Through repeated and in-depth exploration in order to achieve the aforementioned objectives, the inventors discovered that a photoresist material containing a repeating unit of a base polymer having a sulfonate anion bonded to the polymer backbone and a sulfonate cation having a triple-bonded tertiary ester-type acid unstable group can achieve low acid diffusion, excellent acid-induced desorption reactivity, and high affinity for alkaline developers. This results in low acid diffusion, high contrast, and low swelling, thereby providing a photoresist material with improved LWR and CDU, excellent resolution, and a wide process tolerance range, thus completing this 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 having a repeating unit a having a salt structure consisting of a sulfonic acid anion bonded to the polymer backbone and a sulfonium cation represented by the following formula (1).

[0025] [Chemistry 1]

[0026]

[0027] In the formula, p is 0 or 1, q is an integer from 0 to 4, r is 1 or 2, and s is an integer from 1 to 3.

[0028] R 1 It can be a single bond, ether bond, thioether bond, or ester bond.

[0029] R 2 It is a single bond or an alkyldiyl group with 1 to 20 carbon atoms, and the alkyldiyl group may also have a fluorine atom or a hydroxyl group.

[0030] R 3 and R 4Each group is independently a saturated hydrocarbon group having 1 to 12 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alkynyl group having 2 to 8 carbon atoms, or an aryl group having 6 to 12 carbon atoms, and the saturated hydrocarbon group, alkenyl group, alkynyl group, and aryl group may also contain an oxygen atom or a sulfur atom. Furthermore, R 3 and R 4 They can also bond to each other and form rings together with the carbon atoms they are bonded to.

[0031] R 5 It is a hydrogen atom, a saturated hydrocarbon group having 1 to 12 carbon atoms, or an aryl group having 6 to 18 carbon atoms, and the saturated hydrocarbon group and aryl group may also have at least one selected from hydroxyl, a saturated hydrocarbon oxy group having 1 to 6 carbon atoms, a saturated hydrocarbon oxy carbonyl group having 2 to 6 carbon atoms, a nitro group, a cyano group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, an amino group, a trifluoromethyl group, a trifluoromethoxy group, and a trifluoromethyl thio group. However, R 3 When R is a substituted or unsubstituted phenyl group, 5 It is not a hydrogen atom.

[0032] R 6 It may be a hydroxyl, carboxyl, nitro, cyano, fluorine atom, chlorine atom, bromine atom, iodine atom or amino group, or may contain at least one of the following: a saturated hydrocarbon group having 1 to 20 carbon atoms, a saturated hydrocarbon oxy group having 1 to 20 carbon atoms, a saturated hydrocarbon carbonyl oxy group having 2 to 20 carbon atoms, a saturated hydrocarbon oxy carbonyl group having 2 to 20 carbon atoms, or a saturated hydrocarbon sulfonyl oxy group having 1 to 4 carbon atoms.

[0033] R 7 It can also be a hydrocarbon group with 1 to 20 carbon atoms that contains heteroatoms. When s = 1, there are 2 R groups. 7 They can be the same or different from each other, and they can also bond to each other and form a ring together with the sulfur atoms they are bonded to.

[0034] 2. The corrosion-resistant material as in 1, wherein the repeating unit a is represented by the following formula (a1) or (a2).

[0035] [Chemistry 2]

[0036]

[0037] In the formula, R A Each can be a hydrogen atom or a methyl group, independently.

[0038] X 1 It is a single bond or an ester bond.

[0039] X 2 For single key, -X 21 -C(=O)-O- or -X 21 -O-。 X 21It is a hydrocarbon group with 1 to 12 carbon atoms, a phenylene group, or a group with 7 to 18 carbon atoms obtained by combining them, and may also contain a carbonyl group, an ester bond, an ether bond, an iodine atom, or a bromine atom.

[0040] X 3 It can be a single bond, methylene, or ethylene.

[0041] X 4 Single bond, methylene, ethylene, phenylene, methylphenylene, dimethylphenylene, fluorinated phenylene, phenylene substituted with trifluoromethyl, -OX 41 -、-C(=O)-OX 41 -or-C(=O)-NH-X 41 -. X 41 It is an aliphatic alkylene group, phenylene, methylphenylene, dimethylphenylene, fluorinated phenylene, or phenylene substituted with trifluoromethyl, having 1 to 6 carbon atoms, and may also contain carbonyl groups, ester bonds, ether bonds, hydroxyl groups, or halogen atoms.

[0042] Rf 1 ~Rf 4 Each of the following can be independently a hydrogen atom, a fluorine atom, or a trifluoromethyl group, but at least one of them must be a fluorine atom or a trifluoromethyl group. Also, Rf 1 and Rf 2 They can also combine to form carbonyl groups.

[0043] M + The sulfonium cation is represented by formula (1).

[0044] 3. As in 1. or 2., the resist materials contain organic solvents.

[0045] 4. The resist material of any one of 1 to 3, wherein the aforementioned base polymer further comprises repeating units represented by formula (b1) or repeating units represented by formula (b2).

[0046] [Chemistry 3]

[0047]

[0048] In the formula, R A Each can be a hydrogen atom or a methyl group, independently.

[0049] Y 1 It is a single bond, a phenylene or naphthylene group, or contains a linking group with 1 to 12 carbon atoms selected from at least one of ester bonds, ether bonds, and lactone rings.

[0050] Y 2 It is a single bond or an ester bond.

[0051] Y 3 It can be a single bond, an ether bond, or an ester bond.

[0052] R 11 and R 12 Each is an acid-labile group.

[0053] R 13 It can be a fluorine atom, trifluoromethyl, cyano, a saturated hydrocarbon group with 1 to 6 carbon atoms, a saturated hydrocarbon oxy group with 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl group with 2 to 7 carbon atoms, a saturated hydrocarbon carbonyl oxy group with 2 to 7 carbon atoms, or a saturated hydrocarbon oxy carbonyl group with 2 to 7 carbon atoms.

[0054] R 14 It is a single bond or an alkyl diene with 1 to 6 carbon atoms, and part of the -CH2- of the alkyl diene may also be replaced by an ether bond or an ester bond.

[0055] a is 1 or 2. b is an integer from 0 to 4. However, 1 ≤ a + b ≤ 5.

[0056] 5. As in 4., the resist material is a chemically amplified positive resist material.

[0057] 6. The resist materials mentioned in any of 1 to 5 contain surfactants.

[0058] 7. A method for forming a pattern, comprising the following steps:

[0059] A resist film is formed on the substrate using any of the resist materials described in 1. to 6.

[0060] The aforementioned resist film was exposed to high-energy radiation, and

[0061] The previously exposed resist film was developed using a developer.

[0062] 8. The pattern forming method as described in 7, wherein the aforementioned high-energy rays are KrF excimer lasers, ArF excimer lasers, electron beams (EB), or EUV with a wavelength of 3 to 15 nm.

[0063] [The effects of the invention]

[0064] Photoresist materials containing a base polymer comprising repeating unit a, when the aforementioned base polymer further contains acid-labile groups, not only improve the alkali dissolution rate by utilizing the polarity change caused by the acid-catalyzed reaction during exposure, but also, regarding the repeating unit a itself, its unexposed portion is insoluble in the developer, while through exposure, it itself generates carboxyl groups due to the generated acid, further improving the alkali dissolution rate. Utilizing these properties, improved LWR and CDU photoresist materials can be constructed. Detailed Implementation

[0065] [Corrosion Resistance Materials]

[0066] The resist material of the present invention comprises a basic polymer having a repeating unit a, which is a salt structure consisting of a sulfonic acid anion bonded to the polymer backbone and a sulfonate cation having a triple-bonded tertiary ester-type acid unstable group. Since the repeating unit a functions as an acid generator, the aforementioned basic polymer is a polymer-bonded acid generator.

[0067] [Basic Polymers]

[0068] The aforementioned sulfonium cation with a triple bond and an unstable tertiary ester acid group is represented by the following formula (1).

[0069] [Chemistry 4]

[0070]

[0071] In equation (1), p is 0 or 1, q is an integer from 0 to 4, r is 1 or 2, and s is an integer from 1 to 3.

[0072] In equation (1), R 1 It can be a single bond, ether bond, thioether bond, or ester bond, and preferably an ether bond or an ester bond.

[0073] In equation (1), R 2 It is a single bond or an alkyldiyl group with 1 to 20 carbon atoms, and the alkyldiyl group may also have a fluorine atom or a hydroxyl group. Examples of the aforementioned alkyldiyl groups include: methanediyl, ethane-1,1-diyl, ethane-1,2-diyl, propane-1,1-diyl, propane-1,2-diyl, propane-1,3-diyl, propane-2,2-diyl, butane-1,1-diyl, butane-1,2-diyl, butane-1,3-diyl, butane-2,3-diyl, butane-1,4-diyl, 1,1-dimethylethane-1,2-diyl, pentane-1,5-diyl, 2-methylbutane-1,2-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, etc.

[0074] In equation (1), R 3 and R 4 Each group is independently a saturated hydrocarbon group having 1 to 12 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alkynyl group having 2 to 8 carbon atoms, or an aryl group having 6 to 12 carbon atoms, and the saturated hydrocarbon group, alkenyl group, alkynyl group, and aryl group may also contain an oxygen atom or a sulfur atom. Furthermore, R 3 and R 4 They can also bond to each other and form rings together with the carbon atoms they are bonded to.

[0075] R 3 and R 4The saturated hydrocarbon group representing 1 to 12 carbon atoms can be linear, branched, or cyclic. Specific examples include: alkyl groups with 1 to 12 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, neopentyl, and n-hexyl; and cyclic saturated hydrocarbon groups with 3 to 12 carbon atoms such as cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl. 3 and R 4 Examples of alkenyl groups representing 2 to 8 carbon atoms include: vinyl, 1-propenyl, 2-propenyl, butenyl, hexenyl, etc. R 3 and R 4 Examples of alkynyl groups representing 2 to 8 carbon atoms include ethynyl and butynyl. R 3 and R 4 Aryl groups representing 6 to 12 carbon atoms can be exemplified by phenyl, naphthyl, etc.

[0076] In equation (1), R 5 It is a hydrogen atom, a saturated hydrocarbon group having 1 to 12 carbon atoms, or an aryl group having 6 to 18 carbon atoms, and the saturated hydrocarbon group and aryl group may also have at least one selected from hydroxyl, a saturated hydrocarbon oxy group having 1 to 6 carbon atoms, a saturated hydrocarbon oxy carbonyl group having 2 to 6 carbon atoms, a nitro group, a cyano group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, an amino group, a trifluoromethyl group, a trifluoromethoxy group, and a trifluoromethyl thio group. However, R 3 When R is a substituted or unsubstituted phenyl group, 5 It is not a hydrogen atom.

[0077] R 5 The saturated hydrocarbon group representing 1 to 12 carbon atoms can be linear, branched, or cyclic, and specific examples can be listed as follows: and are examples of R. 3 and R 4 The same applies to saturated hydrocarbon groups representing 1 to 12 carbon atoms. R 5 Examples of aryl groups representing carbon numbers from 6 to 18 include: phenyl, 2-methylphenyl, 3-methylphenyl, 4-methylphenyl, 4-ethylphenyl, 4-tert-butylphenyl, 4-n-butylphenyl, 2,4-dimethylphenyl, 2,4,6-trimethylphenyl, naphthyl, anthraceneyl, phenalenyl, pyrene, dihydroindene, fluorene, etc.

[0078] In equation (1), R 6 It may be a hydroxyl, carboxyl, nitro, cyano, fluorine atom, chlorine atom, bromine atom, iodine atom or amino group, or may contain at least one of the following: a saturated hydrocarbon group having 1 to 20 carbon atoms, a saturated hydrocarbon oxy group having 1 to 20 carbon atoms, a saturated hydrocarbon carbonyl oxy group having 2 to 20 carbon atoms, a saturated hydrocarbon oxy carbonyl group having 2 to 20 carbon atoms, or a saturated hydrocarbon sulfonyl oxy group having 1 to 4 carbon atoms.

[0079] R6 The saturated hydrocarbon group, saturated hydrocarbon oxy group, saturated hydrocarbon carbonyl oxy group, saturated hydrocarbon oxy carbonyl group, and saturated hydrocarbon sulfonyl oxy group can be any of the following: straight chain, branched, or cyclic. Specific examples include: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, neopentyl, n-hexyl, n-heptyl, n-octyl, 2-ethylhexyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-pentadecanyl, n-hexadecyl, etc.; cyclic saturated hydrocarbon groups such as cyclopentyl and cyclohexyl.

[0080] In equation (1), R 7 It can also be a hydrocarbon group with 1 to 20 carbon atoms, which may contain heteroatoms. The aforementioned hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include: saturated hydrocarbon groups with 1 to 20 carbon atoms, unsaturated aliphatic hydrocarbon groups with 2 to 20 carbon atoms, aryl groups with 6 to 20 carbon atoms, aralkyl groups with 7 to 20 carbon atoms, and groups obtained by combining them.

[0081] The aforementioned saturated hydrocarbon groups can be any of the following: straight-chain, branched, or cyclic. Specific examples include: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, neopentyl, n-hexyl, n-heptyl, n-octyl, 2-ethylhexyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-pentadecanyl, n-hexadecyl, etc.; cyclic saturated hydrocarbon groups such as cyclopentyl and cyclohexyl.

[0082] The aforementioned unsaturated aliphatic hydrocarbon groups can be any of the following: linear, branched, or cyclic. Specific examples include: vinyl, 1-propenyl, 2-propenyl, butenyl, hexenyl, and other alkenyl groups; ethynyl, propynyl, butynyl, and other alkynyl groups; and cyclohexenyl and other cyclic unsaturated hydrocarbon groups.

[0083] The aforementioned aryl groups can be listed as follows: phenyl, tolyl, ethylphenyl, n-propylphenyl, isopropylphenyl, n-butylphenyl, isobutylphenyl, sec-butylphenyl, tert-butylphenyl, naphthyl, methylnaphthyl, ethylnaphthyl, n-propylnaphthyl, isopropylnaphthyl, n-butylnaphthyl, isobutylnaphthyl, sec-butylnaphthyl, tert-butylnaphthyl, etc.

[0084] Examples of aralkyl groups mentioned above include benzyl and phenethyl.

[0085] Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group can be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms. A portion of the -CH2- group in the aforementioned hydrocarbon group can also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, it may contain hydroxyl groups, carboxyl groups, halogen atoms, cyano groups, amino groups, nitro groups, sulfonyl lactone rings, sulfonyl groups, groups containing sulfonium salts, ether bonds, ester bonds, carbonyl groups, thioether bonds, sulfonyl groups, amide bonds, etc.

[0086] When s=1, there are 2 R 7 They can be the same or different from each other, and they can also bond to each other and form a ring together with the sulfur atoms they are bonded to. In this case, the aforementioned ring should preferably have the structure shown below.

[0087] [Chemistry 5]

[0088]

[0089] In the formula, the dashed lines represent the atomic bonds of the aromatic ring in formula (1).

[0090] The cations of the sulfonium salt represented by formula (1) can be listed below, but are not limited to these.

[0091] [Chemistry 6]

[0092]

[0093] [Chemistry 7]

[0094]

[0095] [Chemistry 8]

[0096]

[0097] [Chemistry 9]

[0098]

[0099] [Chemistry 10]

[0100]

[0101] [Chemistry 11]

[0102]

[0103] [Chemistry 12]

[0104]

[0105] [Chemistry 13]

[0106]

[0107] [Chemistry 14]

[0108]

[0109] [Chemistry 15]

[0110]

[0111] [Chemistry 16]

[0112]

[0113] [Chemistry 17]

[0114]

[0115] [Chemistry 18]

[0116]

[0117] [Chemistry 19]

[0118]

[0119] [Chemistry 20]

[0120]

[0121] [Chemistry 21]

[0122]

[0123] [Chemistry 22]

[0124]

[0125] [Chemistry 23]

[0126]

[0127] [Chemistry 24]

[0128]

[0129] [Chemistry 25]

[0130]

[0131] [Chemistry 26]

[0132]

[0133] [Chemistry 27]

[0134]

[0135] [Chemistry 28]

[0136]

[0137] [Chemistry 29]

[0138]

[0139] [Chemistry 30]

[0140]

[0141] [Chemistry 31]

[0142]

[0143] [Chemistry 32]

[0144]

[0145] [Chemistry 33]

[0146]

[0147] [Chemistry 34]

[0148]

[0149] [Chemistry 35]

[0150]

[0151] [Chemistry 36]

[0152]

[0153] [Chemistry 37]

[0154]

[0155] [Chemistry 38]

[0156]

[0157] [Chemistry 39]

[0158]

[0159] [Chemistry 40]

[0160]

[0161] [Chemistry 41]

[0162]

[0163] [Chemistry 42]

[0164]

[0165] [Chemistry 43]

[0166]

[0167] [Chemistry 44]

[0168]

[0169] [Chemistry 45]

[0170]

[0171] [Chemistry 46]

[0172]

[0173] [Chemistry 47]

[0174]

[0175] [Chemistry 48]

[0176]

[0177] [Chemistry 49]

[0178]

[0179] [Transformation 50]

[0180]

[0181] [Chemistry 51]

[0182]

[0183] [Chemistry 52]

[0184]

[0185] [Chemistry 53]

[0186]

[0187] [Chemistry 54]

[0188]

[0189] [Chemistry 55]

[0190]

[0191] [Chemistry 56]

[0192]

[0193] [Chemistry 57]

[0194]

[0195] [Chem.58]

[0196]

[0197] [Chemistry 59]

[0198]

[0199] [Transformation 60]

[0200]

[0201] [Chemistry 61]

[0202]

[0203] [Chemistry 62]

[0204]

[0205] [Chemistry 63]

[0206]

[0207] [Chemistry 64]

[0208]

[0209] [Chemistry 65]

[0210]

[0211] [Chemistry 66]

[0212]

[0213] [Chemistry 67]

[0214]

[0215] [Chemistry 68]

[0216]

[0217] [Chemistry 69]

[0218]

[0219] [Chemistry 70]

[0220]

[0221] [Chemistry 71]

[0222]

[0223] [Chemistry 72]

[0224]

[0225] [Chemistry 73]

[0226]

[0227] [Chemistry 74]

[0228]

[0229] [Chemistry 75]

[0230]

[0231] [Chemistry 76]

[0232]

[0233] The repeating unit a should preferably be represented by the following formula (a1) (hereinafter also referred to as repeating unit a1) or the following formula (a2) (hereinafter also referred to as repeating unit a2).

[0234] [Chemistry 77]

[0235]

[0236] In equations (a1) and (a2), R A Each can be independently a hydrogen atom or a methyl group. X 1 It is a single bond or an ester bond. X 2 For single key, -X 21 -C(=O)-O- or -X 21 -O-。 X 21 It is a hydrocarbon group with 1 to 12 carbon atoms, a phenylene group, or a group with 7 to 18 carbon atoms obtained by combining them, and may also contain a carbonyl group, an ester bond, an ether bond, an iodine atom, or a bromine atom. X 3 It is a single bond, methylene, or ethylene. X 4 Single bond, methylene, ethylene, phenylene, methylphenylene, dimethylphenylene, fluorinated phenylene, phenylene substituted with trifluoromethyl, -OX 41 -、-C(=O)-OX 41 -or-C(=O)-NH-X 41 -. X 41 It is an aliphatic alkylene group, phenylene, methylphenylene, dimethylphenylene, fluorinated phenylene, or phenylene substituted with trifluoromethyl, having 1 to 6 carbon atoms, and may also contain a carbonyl group, ester bond, ether bond, hydroxyl group, or halogen atom. Rf 1 ~Rf 4 Each of the following can be independently a hydrogen atom, a fluorine atom, or a trifluoromethyl group, but at least one of them must be a fluorine atom or a trifluoromethyl group. Also, Rf 1 and Rf 2 They can also combine to form carbonyl groups. M +The sulfonium cation is represented by formula (1).

[0237] Anions of monomers providing repeating unit a1 can be listed below, but are not limited to. Additionally, in the following formula, R... A Same as above.

[0238] [Chemistry 78]

[0239]

[0240] [Chemistry 79]

[0241]

[0242] [Chemistry 80]

[0243]

[0244] [Chemistry 81]

[0245]

[0246] [Chemistry 82]

[0247]

[0248] [Chemistry 83]

[0249]

[0250] [Chemistry 84]

[0251]

[0252] [Chemistry 85]

[0253]

[0254] [Chemistry 86]

[0255]

[0256] [Chemistry 87]

[0257]

[0258] [Chemistry 88]

[0259]

[0260] [Chemistry 89]

[0261]

[0262] [Chemistry 90]

[0263]

[0264] [Chemistry 91]

[0265]

[0266] Anions of monomers providing repeating unit a2 can be listed below, but are not limited to. Additionally, in the following formula, R... A Same as above.

[0267] [Chemistry 92]

[0268]

[0269] Methods for synthesizing sulfonium salts that provide repeating units a1 or a2 include: methods for ion-exchanging a weak acid salt of the aforementioned sulfonium cation with an ammonium salt having the aforementioned anion.

[0270] When the aforementioned base polymer is a positive resist material, it is preferable to further include repeating units containing acid-labile groups. The repeating units containing acid-labile groups are preferably repeating units represented by formula (b1) (hereinafter also referred to as repeating unit b1) or repeating units represented by formula (b2) (hereinafter also referred to as repeating unit b2). In the exposure section, not only the repeating units b1 or b2 containing acid-labile groups in the aforementioned base polymer, but also the repeating units a1 or a2 containing acid-generating agents will accelerate the dissolution rate of the developer due to the catalytic reaction, thus enabling the production of a positive resist material with extremely high sensitivity.

[0271] [Chemistry 93]

[0272]

[0273] In equations (b1) and (b2), R A Each can be independently a hydrogen atom or a methyl group. Y 1 It is a single bond, a phenylene or naphthylene group, or contains a linking group with 1 to 12 carbon atoms selected from ester bonds, ether bonds, and lactone rings. 2 It is a single bond or an ester bond. Y 3 It can be a single bond, an ether bond, or an ester bond. R 11 and R 12 Each is an acid-labile group, independently. R 13 It can be a fluorine atom, trifluoromethyl, cyano, a saturated hydrocarbon group having 1 to 6 carbon atoms, a saturated hydrocarbon oxy group having 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl group having 2 to 7 carbon atoms, a saturated hydrocarbon carbonyl oxy group having 2 to 7 carbon atoms, or a saturated hydrocarbon oxy carbonyl group having 2 to 7 carbon atoms. R 14 It is a single bond or an alkyldiyl group with 1 to 6 carbon atoms, and part of the -CH2- group may be replaced by an ether bond or an ester bond. a is 1 or 2. b is an integer from 0 to 4. However, 1 ≤ a + b ≤ 5.

[0274] The monomers providing the repeating unit b1 can be listed below, but are not limited to. Additionally, in the following formula, R... A and R 11 Same as above.

[0275] [Chemistry 94]

[0276]

[0277] Monomers providing repeating unit b2 can be listed below, but are not limited to. Additionally, in the following formula, R... A and R 12 Same as above.

[0278] [Chem. 95]

[0279]

[0280] In equations (b1) and (b2), R 11 and R 12 Examples of acid-labile unstable groups can be found in Japanese Patent Application Publication No. 2013-80033 and Japanese Patent Application Publication No. 2013-83821.

[0281] For representative purposes, the aforementioned unstable acid groups can be represented by the following formulas (L-1) to (L-3).

[0282] [Chemistry 96]

[0283]

[0284] In the formula, the dashed lines represent atomic bonds.

[0285] In equations (L-1) and (L-2), R L1 and R L2 Each hydrocarbon group is independently composed of 1 to 40 carbon atoms and may also contain heteroatoms such as oxygen, sulfur, nitrogen, and fluorine atoms. The aforementioned hydrocarbon groups can be saturated or unsaturated, and can be linear, branched, or cyclic. Preferably, the aforementioned hydrocarbon groups are saturated hydrocarbon groups with 1 to 40 carbon atoms or unsaturated hydrocarbon groups with 2 to 40 carbon atoms; saturated hydrocarbon groups with 1 to 20 carbon atoms or unsaturated hydrocarbon groups with 2 to 20 carbon atoms are even more preferred.

[0286] In equation (L-1), c is an integer from 0 to 10, and preferably an integer from 1 to 5.

[0287] In equation (L-2), R L3 and R L4Each group is independently composed of a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and may also contain heteroatoms such as oxygen, sulfur, nitrogen, and fluorine atoms. The aforementioned hydrocarbon groups can be saturated or unsaturated, and can be linear, branched, or cyclic. The aforementioned hydrocarbon groups are preferably saturated hydrocarbon groups having 1 to 20 carbon atoms. Furthermore, R... L2 R L3 and R L4 Any two atoms can also bond to each other and together with the carbon atoms they are bonded to, or carbon atoms and oxygen atoms, form a ring with 3 to 20 carbon atoms. The aforementioned ring is preferably a ring with 4 to 16 carbon atoms, and an alicyclic ring is particularly preferred.

[0288] In equation (L-3), R L5 R L6 and R L7 Each hydrocarbon group is independently composed of 1 to 20 carbon atoms and may also contain heteroatoms such as oxygen, sulfur, nitrogen, and fluorine. The aforementioned hydrocarbon groups can be saturated or unsaturated, and can be linear, branched, or cyclic. The aforementioned hydrocarbon groups are preferably saturated hydrocarbon groups with 1 to 20 carbon atoms. Furthermore, R... L5 R L6 and R L7 Any two atoms can also bond to each other and together with the carbon atoms they bond to form a ring with 3 to 20 carbon atoms. The aforementioned ring is preferably a ring with 4 to 16 carbon atoms, and an alicyclic ring is particularly preferred. This ring may also contain double or triple bonds.

[0289] The acid-instable group represented by formula (L-3) may also be an acid-instable group containing an aromatic group as described in Japanese Patent Nos. 5655754, 5655755, 5655756, 5407941, 5434983, 5565293 and 2007-279699, or an acid-instable group containing a triple bond as described in Japanese Patent No. 2008-268741, or an acid-instable group containing a double or triple bond as described in Japanese Patent No. 2021-50307.

[0290] The aforementioned basic polymer may further include repeating unit c containing phenolic hydroxyl groups as binding groups. Monomers providing repeating unit c can be listed below, but are not limited to these. Additionally, in the following formula, R... A Same as above.

[0291] [Chemistry 97]

[0292]

[0293] The aforementioned basic polymer may also contain repeating units d containing hydroxyl groups other than phenolic hydroxyl groups, lactone rings, sulfonyl rings, ether bonds, ester bonds, sulfonate bonds, carbonyl groups, sulfonyl groups, cyano groups, or carboxyl groups as other close-knit groups. Monomers providing repeating units d are listed below, but are not limited to these. Additionally, in the following formula, R... A Same as above.

[0294] [Chem. 98]

[0295]

[0296] [Chemistry 99]

[0297]

[0298] [Chemistry 100]

[0299]

[0300] [Chemistry 101]

[0301]

[0302] [Chemistry 102]

[0303]

[0304] [Chemistry 103]

[0305]

[0306] [Chemistry 104]

[0307]

[0308] [Chemistry 105]

[0309]

[0310] The aforementioned base polymer may further contain repeating units e derived from indene, benzofuran, benzothiophene, acenaphthene, crromone, coumarin, norcamphediene, or derivatives thereof. Monomers providing repeating units e may be listed below, but are not limited thereto.

[0311] [Chemistry 106]

[0312]

[0313] The aforementioned base polymer may also contain repeating units f derived from styrene, ethylene naphthalene, ethylene anthracene, ethylene pyrene, methylene dihydroindene, ethylene pyridine, or ethylene carbazole.

[0314] In the foregoing base polymer, the repeating units a1 or a2 are necessary. At this time, the content ratios of the repeating units a1, a2, b, c, d, e, and f should be 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. It is better that 0≤a1≤0.4, 0≤a2≤0.4, 0.01≤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. It is even better that 0≤a1≤0.35, 0≤a2≤0.35, 0.02≤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. In addition, a1 + a2 + b1 + b2 + c + d + e + f = 1.0.

[0315] When synthesizing the foregoing base polymer, for example, monomers providing the foregoing repeating units are added with a radical polymerization initiator in an organic solvent and then heated to carry out polymerization.

[0316] Examples of the organic solvents used in the polymerization include toluene, benzene, tetrahydrofuran (THF), diethyl ether, dioxane, etc. Examples of the polymerization initiators include 2,2’-azobisisobutyronitrile (AIBN), 2,2’-azobis(2,4-dimethylvaleronitrile), dimethyl 2,2-azobis(2-methylpropionate), benzoyl peroxide, lauroyl peroxide, etc. The temperature during the polymerization should be 50~80°C. The reaction time should be 2~100 hours, and it is better that it is 5~20 hours.

[0317] When copolymerizing a monomer containing a hydroxyl group, the hydroxyl group can be substituted with an acetal group such as ethoxyethoxy that is easily deprotected by an acid in advance during the polymerization, and deprotection can be carried out using a weak acid and water after the polymerization. It can also be substituted with an acetyl group, a formyl group, a trimethylacetyl group, etc. in advance, and base hydrolysis can be carried out after the polymerization.

[0318] When copolymerizing hydroxystyrene and hydroxyvinylnaphthalene, hydroxystyrene and hydroxyvinylnaphthalene can also be replaced with acetoxystyrene and acetoxyvinylnaphthalene, and the acetoxy group can be deprotected to become hydroxystyrene and hydroxyvinylnaphthalene using the foregoing base hydrolysis after the polymerization.

[0319] The base used in the base hydrolysis can be ammonia water, triethylamine, etc. Also, the reaction temperature should be -20~100°C, and it is better that it is 0~60°C. The reaction time should be 0.2~100 hours, and it is better that it is 0.5~20 hours.

[0320] For the aforementioned base polymer, the equivalent weight-average molecular weight (Mw) of polystyrene obtained by gel permeation chromatography (GPC) using THF as a solvent is preferably 1,000–500,000, and more preferably 2,000–30,000. If the Mw is within the aforementioned range, the resist film exhibits good heat resistance and solubility in alkaline developing solutions.

[0321] Furthermore, when the molecular weight distribution (Mw / Mn) of the aforementioned base polymer is wide, the presence of both low and high molecular weight polymers may lead to concerns about the observation of foreign matter or deterioration of the pattern shape after exposure. As the pattern becomes more regular and refined, the influence of Mw and Mw / Mn tends to increase. Therefore, in order to obtain a resist material suitable for use in fine pattern sizes, the Mw / Mn of the aforementioned base polymer should preferably be 1.0 to 2.0, with a narrow dispersion of 1.0 to 1.5 being particularly desirable.

[0322] The aforementioned basic polymer may also include two or more polymers with different composition ratios, Mw, and Mw / Mn.

[0323] [Organic solvents]

[0324] The corrosion resist material of the present invention may also contain organic solvents. There are no particular limitations on the organic solvents used, provided they are capable of dissolving the aforementioned components and the components described below. Examples of such organic solvents include: ketones such as cyclohexanone, cyclopentanone, methyl-2-n-pentyl ketone, and 2-heptanone as described in paragraphs

[0144] to

[0145] of Japanese Patent Application Publication No. 2008-111103; alcohols such as 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, and diacetone alcohol; and 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 monotert-butyl ether acetate, methyl 2-hydroxyisobutyrate, ethyl 2-hydroxyisobutyrate, propyl 2-hydroxyisobutyrate, butyl 2-hydroxyisobutyrate; and lactones such as γ-butyrolactone.

[0325] In the resist material of the present invention, the content of the aforementioned organic solvent relative to 100 parts by weight of the base polymer is preferably 100 to 10,000 parts by weight, and more preferably 200 to 8,000 parts by weight. The aforementioned organic solvent may be used alone or in combination with two or more solvents.

[0326] [Quenching Agent]

[0327] The resist material of the present invention may also contain a quencher. Furthermore, a quencher refers to a compound that can prevent the diffusion of acid generated from an acid-generating agent in the resist material to the unexposed portion.

[0328] The aforementioned quenching agents can include known basic compounds. Known basic compounds include: primary, secondary, and tertiary aliphatic amines, mixed amines, aromatic amines, heterocyclic amines, nitrogen-containing compounds with carboxyl groups, nitrogen-containing compounds with sulfonyl groups, nitrogen-containing compounds with hydroxyl groups, nitrogen-containing compounds with hydroxyl phenyl groups, alcoholic nitrogen-containing compounds, amides, imides, carbamates, etc. Especially preferred are the primary, secondary, and tertiary amine compounds described in paragraphs

[0146] to

[0164] of Japanese Patent Application Publication No. 2008-111103, amine compounds having hydroxyl groups, ether bonds, ester bonds, lactone rings, cyano groups, sulfonate bonds, or compounds having carbamate groups as described in Japanese Patent No. 3790649. By adding such basic compounds, for example, the diffusion rate of acid in the resist film can be further suppressed or the shape can be modified.

[0329] Furthermore, examples of the aforementioned quenchers include onium salts such as sulfonium salts, urethane salts, and ammonium salts of α-unfluorinated sulfonic acids, carboxylic acids, or fluorinated alkoxides, as described in Japanese Patent Application Publication No. 2008-158339. α-fluorinated sulfonic acids, imide acids, or methyl acids are necessary to deprotect the unstable acid groups of carboxylic acid esters. Through salt exchange with α-unfluorinated onium salts, α-unfluorinated sulfonic acids, carboxylic acids, or fluorinated alcohols are released. Since α-unfluorinated sulfonic acids, carboxylic acids, and fluorinated alcohols do not undergo deprotection reactions, they function as quenchers.

[0330] Such quenchers can be exemplified by, for example, compounds represented by formula (2) (onium salt of sulfonic acid without fluorination at the α-position), compounds represented by formula (3) (onium salt of carboxylic acid), and compounds represented by formula (4) (onium salt of alkoxide).

[0331] [Chemistry 107]

[0332]

[0333] In equation (2), R 101 It is a hydrocarbon group with 1 to 40 carbon atoms, which may contain hydrogen atoms or heteroatoms, but excludes those in which the hydrogen atom at the α-position of the sulfonate group is replaced by a fluorine atom or a fluorinated alkyl group.

[0334] R 101The hydrocarbon groups representing 1 to 40 carbon atoms can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, tert-pentyl, n-pentyl, n-hexyl, n-octyl, 2-ethylhexyl, n-nonyl, n-decyl, etc., alkyl groups with 1 to 40 carbon atoms; cyclopentyl, cyclohexyl, cyclopentylmethyl, cyclopentylethyl, cyclopentylbutyl, cyclohexylmethyl, cyclohexylethyl, cyclohexylbutyl, norcamphenyl, tricyclic [5.2.1.0] 2,6 Cyclic saturated hydrocarbon groups with 3 to 40 carbon atoms, such as decyl, adamantyl, and adamantylmethyl; alkenyl groups with 2 to 40 carbon atoms, such as vinyl, allyl, propenyl, butenyl, and hexenyl; cyclic unsaturated aliphatic hydrocarbon groups with 3 to 40 carbon atoms, such as cyclohexenyl; aryl groups with 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, etc.), 2,4,6-triisopropylphenyl, alkylnaphthyl (methylnaphthyl, ethylnaphthyl, etc.), and dialkylnaphthyl (dimethylnaphthyl, diethylnaphthyl, etc.); and aralkyl groups with 7 to 40 carbon atoms, such as benzyl, 1-phenylethyl, and 2-phenylethyl.

[0335] Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group may be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms. A portion of the -CH2- group in the aforementioned hydrocarbon group may also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, it may contain hydroxyl groups, cyano groups, carbonyl groups, ether bonds, ester bonds, sulfonate bonds, carbonate bonds, lactone rings, sulfonolactone rings, carboxylic anhydrides (-C(=O)-OC(=O)-), haloalkyl groups, etc. Examples of hydrocarbon groups containing heteroatoms include: heteroaryl groups such as thiophene; 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; aryloxoalkyl groups such as 2-phenyl-2-oxoethyl, 2-(1-naphthyl)-2-oxoethyl, and 2-(2-naphthyl)-2-oxoethyl; and aryloxoalkyl groups such as 2-aryl-2-oxoethyl.

[0336] In equation (3), R 102 It can also contain hydrocarbon groups with 1 to 40 carbon atoms and heteroatoms. R 102 The hydrocarbon group can be listed and exemplified as R 101The same applies to hydrocarbon groups. Other specific examples can also be listed: fluorinated alkyl groups such as trifluoromethyl, trifluoroethyl, 2,2,2-trifluoro-1-methyl-1-hydroxyethyl, and 2,2,2-trifluoro-1-(trifluoromethyl)-1-hydroxyethyl; fluorinated aryl groups such as pentafluorophenyl and 4-trifluoromethylphenyl.

[0337] In equation (4), R 103 It is a saturated hydrocarbon group having at least 3 fluorine atoms and having 1 to 8 carbon atoms, or an aryl group having at least 3 fluorine atoms and having 6 to 10 carbon atoms, and may also contain a nitro group.

[0338] In equations (2), (3) and (4), Mq + The cation is an onium cation. The aforementioned onium cation is preferably a sulfonium cation, monium cation, or ammonium cation, with a sulfonium cation being more preferred. Examples of sulfonium cations include those described in Japanese Patent Application Publication No. 2017-219836.

[0339] Alternatively, the sulfonium salt of a carboxylic acid containing an iodinated benzene ring, represented by formula (5), can ideally be used as a quencher.

[0340] [Chemistry 108]

[0341]

[0342] In equation (5), R 201 The hydroxyl, fluorine, chlorine, bromine, amino, nitro, cyano, or hydrogen atom may be partially or wholly substituted by a halogen atom, and may be a saturated hydrocarbon group having 1 to 6 carbon atoms, a saturated hydrocarbon oxy group having 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl oxy group having 2 to 6 carbon atoms, or a saturated hydrocarbon sulfonyl oxy group having 1 to 4 carbon atoms, or -N(R 201A )-C(=O)-R 201B or -N(R) 201A )-C(=O)-OR 201B R 201A It consists of a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms. R 201B It is a saturated hydrocarbon group with 1 to 6 carbon atoms or an unsaturated aliphatic hydrocarbon group with 2 to 8 carbon atoms.

[0343] In equation (5), x' is an integer from 1 to 5. y' is an integer from 0 to 3. z' is an integer from 1 to 3. L 11 It is a single bond or a (z'+1) valence linking group having 1 to 20 carbon atoms, and may also contain at least one selected from ether bonds, carbonyl groups, ester bonds, amide bonds, sulfonyl lactone rings, lactam rings, carbonate bonds, halogen atoms, hydroxyl groups, and carboxyl groups. The aforementioned saturated hydrocarbon groups, saturated hydrocarbon oxy groups, saturated hydrocarbon carbonyl oxy groups, and saturated hydrocarbon sulfonyl oxy groups may be linear, branched, or cyclic. When y' and / or z' are 2 or more, each R... 201 They can be the same or different.

[0344] In equation (5), R 202 R 203 and R 204 Each hydrocarbon group consists of 1 to 20 carbon atoms, which may be halogen atoms or contain heteroatoms. The aforementioned hydrocarbon groups may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples can be listed as follows: and R is exemplified as in formula (1). 7 The same applies to the hydrocarbon group. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group may be replaced by hydroxyl, carboxyl, halogen, oxo, cyano, nitro, sulfonyl lactone ring, sulfonyl, or sulfonate-containing groups; and a portion of the -CH2- group in the aforementioned hydrocarbon group may be replaced by ether, ester, carbonyl, amide, carbonate, or sulfonate bonds. Also, R 202 With R 203 They can also bond to each other and form rings together with the sulfur atoms they are bonded to.

[0345] Specific examples of compounds represented by formula (5) can be listed in Japanese Patent Application Publication No. 2017-219836 and Japanese Patent Application Publication No. 2021-91666.

[0346] Other examples of the aforementioned quenchers include the polymer-type quencher disclosed in Japanese Patent Application Publication No. 2008-239918. This quencher improves the rectangularity of the resist pattern by aligning with the surface of the resist film. The polymer-type quencher also prevents film loss and dome-shaped formation of the pattern when using a protective film for immersion exposure.

[0347] In addition, betaine-type sulfonium salts described in Japanese Patent No. 6848776 and Japanese Patent Application Publication No. 2020-37544, fluorine-free methyl acid described in Japanese Patent Application Publication No. 2020-55797, sulfonamide sulfonium salts described in Japanese Patent No. 5807552, and iodine-containing sulfonamide sulfonium salts described in Japanese Patent Application Publication No. 2019-211751 can also be used as quenching agents.

[0348] When the corrosion resist material of the present invention contains the aforementioned quencher, its content relative to 100 parts by weight of the base polymer is preferably 0 to 5 parts by weight, and more preferably 0 to 4 parts by weight. The aforementioned quencher can be used alone or in combination of two or more.

[0349] [Other ingredients]

[0350] In addition to the aforementioned components, the resist material of the present invention may also contain sulfonate or monazite-type acid generators (hereinafter referred to as other acid generators), surfactants, dissolution inhibitors, water repellency improvers, acetylene alcohols, etc.

[0351] Other acid-generating agents mentioned above include compounds that generate acids in response to active light or radiation (photoacid generators). Any component of the photoacid generator that generates acids by irradiation with high-energy rays is acceptable, but it is preferable that it generates sulfonic acid, imine acid, or methyl acid. Ideal photoacid generators include: sulfonium salts, sulfonium salts, sulfonyl diazomethanes, N-sulfonyloxyimide, oxime-O-sulfonate type acid generators, etc. Specific examples of acid generators can be cited in paragraphs

[0122] to

[0142] of Japanese Patent Application Publication No. 2008-111103, Japanese Patent Application Publication No. 2018-5224, and Japanese Patent Application Publication No. 2018-25789. Especially for EUV resist materials, sulfonium salts or sulfonium salts containing iodine atoms, as described in Japanese Patent Nos. 6720926 and 6743781, are ideally suitable. When the resist material of the present invention contains other acid generating agents, their content relative to 100 parts by weight of the base polymer is preferably 0 to 200 parts by weight, and more preferably 0.1 to 100 parts by weight.

[0352] The aforementioned surfactants can be exemplified by paragraphs

[0165] to

[0166] of Japanese Patent Application Publication No. 2008-111103. By adding surfactants, the coatability of the resist material can be further improved or controlled. When the resist material of the present invention contains the aforementioned surfactants, their content is preferably 0.0001 to 10 parts by weight relative to 100 parts by weight of the base polymer. The aforementioned surfactants can be used alone or in combination of two or more.

[0353] When the resist material of the present invention is positive, by incorporating a dissolution inhibitor, the difference in dissolution rate between the exposed and unexposed areas can be further increased, and the resolution can be further improved. Regarding the aforementioned dissolution inhibitor, its molecular weight is preferably 100 to 1,000, more preferably 150 to 800, and examples include compounds containing two or more phenolic hydroxyl groups in the molecule, in which the hydrogen atom of the phenolic hydroxyl group is replaced by an acid-unstable group at a ratio of 0 to 100 mol% overall, or compounds containing a carboxyl group in the molecule, in which the hydrogen atom of the carboxyl group is replaced by an acid-unstable group at an average ratio of 50 to 100 mol% overall. Specific examples include compounds in which the hydrogen atoms of the hydroxyl and carboxyl groups of bisphenol A, triphenol, phenolphthalein, cresol phenolic varnish resin, naphtholic acid, adamantane carboxylic acid, and cholic acid are replaced by acid-unstable groups, as described in paragraphs

[0155] to

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

[0354] When the resist material of the present invention is positive and contains the aforementioned dissolution inhibitor, its content relative to 100 parts by weight of the base polymer is preferably 0 to 50 parts by weight, and more preferably 5 to 40 parts by weight. The aforementioned dissolution inhibitor may be used alone or in combination of two or more.

[0355] The aforementioned water-repellent improver enhances the water repellency of the resist film surface and can be used in immersion lithography without a topcoat. The aforementioned water-repellent improver is preferably a polymer containing fluorinated alkyl groups, or a polymer with a specific structure containing 1,1,1,3,3,3-hexafluoro-2-propanol residues, as exemplified in Japanese Patent Application Publication Nos. 2007-297590 and 2008-111103. The aforementioned water-repellent improver needs to be soluble in alkaline or organic solvent developing solutions. The aforementioned specific water-repellent improver containing 1,1,1,3,3,3-hexafluoro-2-propanol residues exhibits good solubility in developing solutions. Regarding water-repellent improvers, polymers containing repeating units containing amino or amine salts are highly effective in preventing acid evaporation during PEB development and thus preventing poor opening of the hole pattern after development. When the corrosion-resistant material of the present invention contains the aforementioned water-repellent improver, its content relative to 100 parts by weight of the base polymer is preferably 0 to 20 parts by weight, and more preferably 0.5 to 10 parts by weight. The aforementioned water-repellent improver can be used alone or in combination of two or more.

[0356] The aforementioned acetylenic alcohols can be exemplified by paragraphs

[0179] to

[0182] of Japanese Patent Application Publication No. 2008-122932. When the resist material of the present invention contains acetylenic alcohols, their content is preferably 0 to 5 parts by mass relative to 100 parts by mass of the base polymer. The aforementioned acetylenic alcohols can be used alone or in combination of two or more.

[0357] The resist material of the present invention can be prepared by thoroughly mixing the aforementioned components, adjusting their sensitivity and film thickness to a predetermined range, and then filtering the resulting solution. The filtration step is important to reduce defects in the developed resist pattern. The aperture of the membrane used for filtration should preferably be 1 μm or less, more preferably 10 nm or less, and even more preferably 5 nm or less; the smaller the aperture, the better it can suppress defects in fine patterns. Examples of membrane materials include: tetrafluoroethylene, polyethylene, polypropylene, nylon, polyurethane, polycarbonate, polyimide, polyamide-imide, polysulfone, etc. Membranes with improved adsorption capacity due to surface modification of tetrafluoroethylene, polyethylene, polypropylene, etc., can also be used. Since tetrafluoroethylene, polyethylene, and polypropylene are non-polar, they do not possess the same gel and metal ion adsorption capacity as nylon, polyurethane, polycarbonate, and polyimide membranes, which utilize polarity. However, surface modification with polar functional groups can improve the adsorption capacity for gels and metal ions. In particular, by surface-modifying polyethylene and polypropylene membranes, which can form membranes with smaller apertures, not only can fine particles be reduced, but also polar particles and metal ions can be reduced. Membranes formed by laminating membranes of different materials or by laminating membranes of different pore sizes can also be used.

[0358] Membranes with ion exchange capabilities can also be used. When using an ion exchange membrane that adsorbs cations, the adsorption of metal ions can reduce metal impurities.

[0359] Multiple filter media can be connected during filtration. The membrane types and diameters of the multiple filter media can be the same or different. Filtration can be carried out in piping connecting multiple containers, or in a single container with an outlet and inlet connected by piping for circulation filtration. The filter media used for filtration can be connected in straight lines or in parallel.

[0360] [Pattern Formation Method]

[0361] When the resist material of the present invention is used in the manufacture of various integrated circuits, known photolithography techniques can be applied. For example, a patterning method may include the following steps: using the aforementioned resist material to form a resist film on a substrate, exposing the aforementioned resist film to high-energy rays, and developing the exposed resist film using a developer.

[0362] First, the resist material of the present invention is coated onto a substrate for integrated circuit manufacturing (Si, SiO2, SiN, SiON, TiN, WSi, BPSG, SOG, organic antireflective film, etc.) or a substrate for mask circuit manufacturing (Cr, CrO, CrON, CrN, MoSi2, SiO2, MoSi2 multilayer film, Ta, TaN, TaCN, Ru, Nb, Mo, Mn, Co, Ni or alloys thereof, etc.) using a suitable coating method such as spin coating, roll coating, flow coating, dip coating, spray coating, or blade coating, with a coating film thickness of 0.01 to 2 μm. The resist film is then formed by pre-baking the material on a hot plate, preferably at 60 to 150°C for 10 seconds to 30 minutes, or more preferably at 80 to 120°C for 30 seconds to 20 minutes.

[0363] Then, the aforementioned photoresist film is exposed using high-energy radiation. Examples of such high-energy radiation include: ultraviolet light, far ultraviolet light, EB, EUV with wavelengths of 3–15 nm, X-rays, soft X-rays, excimer lasers, gamma rays, and synchrotron radiation. When using ultraviolet light, far ultraviolet light, EUV, X-rays, soft X-rays, excimer lasers, gamma rays, or synchrotron radiation as the aforementioned high-energy radiation, a mask for forming the desired pattern can be used, with an exposure dose preferably of approximately 1–200 mJ / cm². 2 And it becomes approximately 10–100 mJ / cm 2 A better method of irradiation is to use EB as a high-energy ray. When using EB as a high-energy ray, the exposure dose should be approximately 0.1–300 μC / cm. 2 And preferably about 0.5 to 200 μC / cm 2 The pattern is drawn using a mask to form the desired pattern or directly. Furthermore, the resist material of the present invention is particularly suitable for micro-patterning using high-energy radiation such as KrF excimer lasers, ArF excimer lasers, EB, EUV, X-rays, soft X-rays, gamma rays, and synchrotron radiation, especially for micro-patterning using EB or EUV.

[0364] After exposure, PEB can be carried out on a heating plate or in an oven at a temperature of 30–150°C for 10–30 seconds, preferably 50–120°C for 30–20 seconds, or it can be omitted.

[0365] After exposure or PEB, the exposed resist film is developed using a developing solution of 0.1–10% by mass, preferably 2–5% by mass, of alkaline aqueous solutions such as tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), tetrapropylammonium hydroxide (TPAH), or tetrabutylammonium hydroxide (TBAH) for 3 seconds to 3 minutes, preferably 5 seconds to 2 minutes, using common methods such as dip, immersion, or spray methods to form the desired pattern. When using a positive resist material, the exposed areas dissolve in the developing solution, while the unexposed areas do not, forming the desired positive pattern on the substrate. When using a negative resist material, the opposite occurs: the exposed areas do not dissolve in the developing solution, while the unexposed areas dissolve.

[0366] Positive resist materials containing base polymers with acid-instable groups can also be used, and negative patterns can be obtained by developing with organic solvents. Examples of developers used in this case include: 2-octanone, 2-nonanone, 2-heptanone, 3-heptanone, 4-heptanone, 2-hexanone, 3-hexanone, diisobutyl ketone, methylcyclohexanone, acetophenone, methyl acetophenone, propyl acetate, butyl acetate, isobutyl acetate, amyl acetate, butyl acetate, isoamyl acetate, propyl formate, butyl formate, isobutyl formate, amyl formate, methyl valerate, methyl valerate, methyl crotonate, croton... Ethyl propionate, 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, ethyl formate, methyl 3-phenylpropionate, benzyl propionate, ethyl phenylacetate, 2-phenylethyl acetate, etc. These organic solvents can be used alone or in combination of two or more.

[0367] Rinsing is performed at the end of development. The rinsing solution should be a solvent that is miscible with the developer and does not dissolve the resist film. Ideally, solvents such as alcohols with 3 to 10 carbon atoms, ether compounds with 8 to 12 carbon atoms, alkanes, alkenes, alkynes, and aromatic solvents with 6 to 12 carbon atoms should be used.

[0368] Alcohols with 3 to 10 carbon atoms mentioned above include: n-propanol, isopropanol, 1-butanol, 2-butanol, isobutanol, tert-butanol, 1-pentanol, 2-pentanol, 3-pentanol, tert-pentanol, neopentanol, 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, 1-octanol, etc.

[0369] Examples of ether compounds with 8 to 12 carbon atoms include: di-n-butyl ether, diisobutyl ether, di(sec-butyl) ether, di-n-pentyl ether, diisopentyl ether, di(sec-pentyl) ether, di(tert-pentyl) ether, di-n-hexyl ether, etc.

[0370] Examples of alkanes with 6 to 12 carbon atoms include: hexane, heptane, octane, nonane, decane, undecane, dodecane, methylcyclopentane, dimethylcyclopentane, cyclohexane, methylcyclohexane, dimethylcyclohexane, cycloheptane, cyclooctane, and cyclononane. Examples of alkenes with 6 to 12 carbon atoms include: hexene, heptene, octene, cyclohexene, methylcyclohexene, dimethylcyclohexene, cycloheptene, and cyclooctene. Examples of alkynes with 6 to 12 carbon atoms include: hexyne, heptyne, and octyne.

[0371] The solvents of the aforementioned aromatic family include: toluene, xylene, ethylbenzene, cumene, tert-butylbenzene, mesitylene, etc.

[0372] Rinsing can reduce the collapse of the resist pattern and the occurrence of defects. Furthermore, rinsing is not always necessary; omitting rinsing can reduce the amount of solvent used.

[0373] The developed hole and groove patterns can also be shrunk using heat transfer, RELACS, or DSA techniques. A shrinking agent is applied to the hole pattern, and during baking, the diffusion of an acid catalyst from the resist film causes cross-linking of the shrinking agent on the surface of the resist film. The shrinking agent adheres to the sidewalls of the hole pattern. The baking temperature is preferably 70–180°C, with 80–170°C being more ideal, and the baking time is preferably 10–300 seconds. This removes excess shrinking agent and reduces the size of the hole pattern.

[0374] [Example]

[0375] The present invention will be specifically described below with examples of synthesis, embodiments and comparative examples, but the present invention is not limited to the following embodiments.

[0376] The monomers PM-1 to PM-32, cPM-1 to cPM-3, AM-1 to AM-3, and FM-1 used in the synthesis of the basic polymer are described below. PM-1 to PM-32 are synthesized by ion exchange between ammonium salts of fluorinated sulfonic acid providing the following anions and sulfonium chloride providing the following cations. Furthermore, the polymer's Mw is a polystyrene conversion value determined using GPC with THF as a solvent.

[0377] [Chemistry 109]

[0378]

[0379] [Chemical 110]

[0380]

[0381] [Chemistry 111]

[0382]

[0383] [Chemistry 112]

[0384]

[0385] [Chemistry 113]

[0386]

[0387] [Chemistry 114]

[0388]

[0389] [Chemistry 115]

[0390]

[0391] [Chemistry 116]

[0392]

[0393] [Chemistry 117]

[0394]

[0395] [Chemistry 118]

[0396]

[0397] [Chemistry 119]

[0398]

[0399] [Synthetic Example 1] Synthesis of Polymer P-1

[0400] 8.4 g of 1-methyl-1-cyclopentyl methacrylate, 4.8 g of 4-hydroxystyrene, 9.1 g of PM-1, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-1. The composition of polymer P-1 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0401] [Chemistry 120]

[0402]

[0403] [Synthetic Example 2] Synthesis of Polymer P-2

[0404] 11.1 g of AM-1, 4.8 g of 3-hydroxystyrene, 9.3 g of PM-2, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-2. The composition of polymer P-2 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0405] [Chemistry 121]

[0406]

[0407] [Synthetic Example 3] Synthesis of Polymer P-3

[0408] 11.1 g of AM-1, 4.8 g of 3-hydroxystyrene, 9.2 g of PM-3, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-3. The composition of polymer P-3 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0409] [Chemistry 122]

[0410]

[0411] [Synthetic Example 4] Synthesis of Polymer P-4

[0412] 7.8 g of AM-1, 3.6 g of AM-3, 4.8 g of 3-hydroxystyrene, 8.6 g of PM-4, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-4. The composition of polymer P-4 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0413] [Chemistry 123]

[0414]

[0415] [Synthetic Example 5] Synthesis of Polymer P-5

[0416] 11.9 g of AM-2, 5.2 g of 3-hydroxystyrene, 9.9 g of PM-5, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-5. The composition of polymer P-5 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0417] [Chemistry 124]

[0418]

[0419] [Synthetic Example 6] Synthesis of Polymer P-6

[0420] 11.1 g of AM-1, 4.8 g of 3-hydroxystyrene, 9.4 g of PM-6, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-6. The composition of polymer P-6 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0421] [Chemistry 125]

[0422]

[0423] [Synthesis Example 7] Synthesis of Polymer P-7

[0424] 11.1 g of AM-1, 3.4 g of 3-hydroxystyrene, 3.2 g of monomer FM-1, 12.3 g of PM-7, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-7. The composition of polymer P-7 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0425] [Chemistry 126]

[0426]

[0427] [Synthetic Example 8] Synthesis of Polymer P-8

[0428] 11.1 g of AM-1, 4.8 g of 3-hydroxystyrene, 9.4 g of PM-8, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-8. The composition of polymer P-8 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0429] [Chemistry 127]

[0430]

[0431] [Synthetic Example 9] Synthesis of Polymer P-9

[0432] 11.1 g of AM-1, 4.8 g of 3-hydroxystyrene, 9.6 g of PM-9, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-9. The composition of polymer P-9 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0433] [Chemistry 128]

[0434]

[0435] [Synthetic Example 10] Synthesis of Polymer P-10

[0436] 11.1 g of AM-1, 4.8 g of 3-hydroxystyrene, 10.1 g of PM-10, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-10. The composition of polymer P-10 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0437] [Chemistry 129]

[0438]

[0439] [Synthetic Example 11] Synthesis of Polymer P-11

[0440] 11.1 g of AM-1, 4.8 g of 3-hydroxystyrene, 9.7 g of PM-11, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-11. The composition of polymer P-11 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0441] [Chemistry 130]

[0442]

[0443] [Synthetic Example 12] Synthesis of Polymer P-12

[0444] 11.1 g of AM-1, 4.8 g of 3-hydroxystyrene, 9.7 g of PM-12, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-12. The composition of polymer P-12 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0445] [Chemistry 131]

[0446]

[0447] [Synthetic Example 13] Synthesis of Polymer P-13

[0448] 11.1 g of AM-1, 4.8 g of 3-hydroxystyrene, 9.6 g of PM-13, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-13. The composition of polymer P-13 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0449] [Chemistry 132]

[0450]

[0451] [Synthetic Example 14] Synthesis of Polymer P-14

[0452] 11.1 g of AM-1, 4.8 g of 3-hydroxystyrene, 10.6 g of PM-14, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-14. The composition of polymer P-14 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0453] [Chemistry 133]

[0454]

[0455] [Synthetic Example 15] Synthesis of Polymer P-15

[0456] 11.1 g of AM-1, 4.8 g of 3-hydroxystyrene, 10.4 g of PM-15, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-15. The composition of polymer P-15 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0457] [Chemistry 134]

[0458]

[0459] [Synthetic Example 16] Synthesis of Polymer P-16

[0460] 11.1 g of AM-1, 4.8 g of 3-hydroxystyrene, 10.4 g of PM-16, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-16. The composition of polymer P-16 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0461] [Chemistry 135]

[0462]

[0463] [Synthetic Example 17] Synthesis of Polymer P-17

[0464] 11.1 g of AM-1, 4.8 g of 3-hydroxystyrene, 10.4 g of PM-17, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-17. The composition of polymer P-17 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0465] [Chemistry 136]

[0466]

[0467] [Synthetic Example 18] Synthesis of Polymer P-18

[0468] 8.4 g of 1-methyl-1-cyclopentyl methacrylate, 4.8 g of 3-hydroxystyrene, 9.2 g of PM-18, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-18. The composition of polymer P-18 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0469] [Chemistry 137]

[0470]

[0471] [Synthetic Example 19] Synthesis of Polymer P-19

[0472] 8.4 g of 1-methyl-1-cyclopentyl methacrylate, 4.8 g of 3-hydroxystyrene, 9.6 g of PM-19, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-19. The composition of polymer P-19 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0473] [Chemistry 138]

[0474]

[0475] [Synthetic Example 20] Synthesis of Polymer P-20

[0476] 8.4 g of 1-methyl-1-cyclopentyl methacrylate, 4.8 g of 3-hydroxystyrene, 9.4 g of PM-20, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-20. The composition of polymer P-20 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0477] [Chemistry 139]

[0478]

[0479] [Synthetic Example 21] Synthesis of Polymer P-21

[0480] 8.4 g of 1-methyl-1-cyclopentyl methacrylate, 4.8 g of 3-hydroxystyrene, 9.5 g of PM-21, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-21. The composition of polymer P-21 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0481] [Chemistry 140]

[0482]

[0483] [Synthesis Example 22] Synthesis of Polymer P-22

[0484] 8.4 g of 1-methyl-1-cyclopentyl methacrylate, 4.8 g of 3-hydroxystyrene, 9.4 g of PM-22, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-22. The composition of polymer P-22 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0485] [Chemistry 141]

[0486]

[0487] [Synthesis Example 23] Synthesis of Polymer P-23

[0488] 8.4 g of 1-methyl-1-cyclopentyl methacrylate, 4.8 g of 3-hydroxystyrene, 9.7 g of PM-23, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-23. The composition of polymer P-23 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0489] [Chemistry 142]

[0490]

[0491] [Synthetic Example 24] Synthesis of Polymer P-24

[0492] 8.4 g of 1-methyl-1-cyclopentyl methacrylate, 4.8 g of 3-hydroxystyrene, 9.7 g of PM-24, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-24. The composition of polymer P-24 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0493] [Chemistry 143]

[0494]

[0495] [Synthetic Example 25] Synthesis of Polymer P-25

[0496] 8.4 g of 1-methyl-1-cyclopentyl methacrylate, 4.8 g of 3-hydroxystyrene, 9.7 g of PM-25, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-25. The composition of polymer P-25 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0497] [Chemistry 144]

[0498]

[0499] [Synthesis Example 26] Synthesis of Polymer P-26

[0500] 8.4 g of 1-methyl-1-cyclopentyl methacrylate, 4.8 g of 3-hydroxystyrene, 9.8 g of PM-26, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-26. The composition of polymer P-26 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0501] [Chemistry 145]

[0502]

[0503] [Synthesis Example 27] Synthesis of Polymer P-27

[0504] 8.4 g of 1-methyl-1-cyclopentyl methacrylate, 4.8 g of 3-hydroxystyrene, 10.7 g of PM-27, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-27. The composition of polymer P-27 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0505] [Chemistry 146]

[0506]

[0507] [Synthetic Example 28] Synthesis of Polymer P-28

[0508] 8.4 g of 1-methyl-1-cyclopentyl methacrylate, 4.8 g of 3-hydroxystyrene, 10.7 g of PM-28, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-28. The composition of polymer P-28 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0509] [Chemistry 147]

[0510]

[0511] [Synthesis Example 29] Synthesis of Polymer P-29

[0512] 8.4 g of 1-methyl-1-cyclopentyl methacrylate, 4.8 g of 3-hydroxystyrene, 10.1 g of PM-29, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-29. The composition of polymer P-29 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0513] [Chemistry 148]

[0514]

[0515] [Synthetic Example 30] Synthesis of Polymer P-30

[0516] 8.4 g of 1-methyl-1-cyclopentyl methacrylate, 4.8 g of 3-hydroxystyrene, 10.1 g of PM-30, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-30. The composition of polymer P-30 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0517] [Chemistry 149]

[0518]

[0519] [Synthetic Example 31] Synthesis of Polymer P-31

[0520] 8.4 g of 1-methyl-1-cyclopentyl methacrylate, 4.8 g of 3-hydroxystyrene, 9.7 g of PM-31, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-31. The composition of polymer P-31 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0521] [Chemistry 150]

[0522]

[0523] [Synthetic Example 32] Synthesis of Polymer P-32

[0524] 8.4 g of 1-methyl-1-cyclopentyl methacrylate, 4.8 g of 3-hydroxystyrene, 9.8 g of PM-32, and 40 g of THF as solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under nitrogen atmosphere, and the degassing and nitrogen purging were repeated three times. After heating to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C, allowing the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The resulting white solid was dried under reduced pressure at 60 °C to obtain polymer P-32. The composition of polymer P-32 was determined using... 13 C-NMR and 1 H-NMR was used for confirmation, and Mw and Mw / Mn were confirmed using GPC.

[0525] [Chemistry 151]

[0526]

[0527] [Comparative Synthesis Example 1] Synthesis of Comparative Polymer cP-1

[0528] PM-1 was changed to cPM-1, and otherwise the comparative polymer cP-1 was synthesized using the same method as in Synthesis Example 1.

[0529] [Chemistry 152]

[0530]

[0531] [Comparative Synthesis Example 2] Synthesis of Comparative Polymer cP-2

[0532] PM-1 was changed to cPM-2, and otherwise the comparative polymer cP-2 was synthesized using the same method as in Synthesis Example 1.

[0533] [Chemistry 153]

[0534]

[0535] [Comparative Synthesis Example 3] Comparative Synthesis of Polymer cP-3

[0536] PM-1 was replaced with cPM-3, and otherwise the comparative polymer cP-3 was synthesized using the same method as in Synthesis Example 1.

[0537] [Chemistry 154]

[0538]

[0539] [Examples 1-33, Comparative Examples 1-3] Preparation and Evaluation of Corrosion Resist Materials

[0540] (1) Preparation of corrosion-resistant materials

[0541] A corrosion resist material was prepared by dissolving the components in a solvent containing 100 ppm of Polyfox PF-636 (manufactured by OMNOVA Corporation) as a surfactant, according to the compositions shown in Tables 1 to 3, and then filtering the solution through a filter medium with a size of 0.2 μm.

[0542] The components are described in Tables 1-3 as follows.

[0543] • Organic solvent: PGMEA (propylene glycol monomethyl ether acetate)

[0544] EL (ethyl lactate)

[0545] DAA (diacetone alcohol)

[0546] • Acid generator: PAG-1

[0547] [Chemistry 155]

[0548]

[0549] Quenching agents: Q-1 to Q-3

[0550] [Chemistry 156]

[0551]

[0552] (2) Evaluation of EUV lithography

[0553] The photoresist materials shown in Tables 1-3 were spin-coated onto a Si substrate with a 20 nm thick silicon-containing spin-coated hard mask SHB-A940 (43% by mass) manufactured by Shin-Etsu Chemical Co., Ltd. The substrate was pre-baked at 105°C for 60 seconds using a hot plate to obtain a 50 nm thick photoresist film. The aforementioned photoresist film was exposed using an ASML EUV scanning exposure machine NXE3400 (NA 0.33, σ 0.9 / 0.6, quadrupole illumination, 40 nm pitch, +20% tolerance hole pattern mask on wafer). PEB was applied for 60 seconds on a hot plate at the temperatures listed in Tables 1-3, followed by 30 seconds of development with a 2.38% by mass TMAH aqueous solution to form a 20 nm hole pattern.

[0554] Using a Hitachi High-Tech (CG6300) length-measuring SEM, the exposure was measured when the aperture size was 20 nm, and this was defined as the sensitivity. Furthermore, the size of 50 apertures at this time was measured, and the standard deviation (σ) calculated from these results was defined as three times the standard deviation (3σ) as the CDU. The results are shown in Tables 1-3.

[0555] [Table 1]

[0556]

[0557] [Table 2]

[0558]

[0559] [Table 3]

[0560]

[0561] As shown in Tables 1-3, the resist material of the present invention, which contains repeating units of a sulfonate structure consisting of a sulfonate anion bonded to the polymer backbone and a sulfonate cation having a triple bonded tertiary ester-type acid unstable group as an acid generator, has good CDU.

Claims

1. A corrosion resist material comprising: a basic polymer having a repeating unit a having a salt structure consisting of a sulfonic acid anion bonded to the polymer backbone and a sulfonium cation represented by the following formula (1); In the formula, p is 0 or 1, q is an integer from 0 to 4, r is 1 or 2, and s is an integer from 1 to 3; R 1 is a single bond, an ether bond, a thioether bond or an ester bond; R 2 It is a single bond or an alkyl diene with 1 to 20 carbon atoms, and the alkyl diene may also have a fluorine atom or a hydroxyl group; R 3 and R 4 Each group is independently a saturated hydrocarbon group having 1 to 12 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alkynyl group having 2 to 8 carbon atoms, or an aryl group having 6 to 12 carbon atoms, and the saturated hydrocarbon group, alkenyl group, alkynyl group, and aryl group may also contain oxygen atoms or sulfur atoms; furthermore, R 3 and R 4 They can also bond to each other and form rings together with the carbon atoms they are bonded to; R 5 It is a hydrogen atom, a saturated hydrocarbon group having 1 to 12 carbon atoms, or an aryl group having 6 to 18 carbon atoms, and the saturated hydrocarbon group and aryl group may also have at least one selected from hydroxyl, a saturated hydrocarbon oxy group having 1 to 6 carbon atoms, a saturated hydrocarbon oxy carbonyl group having 2 to 6 carbon atoms, a nitro group, a cyano group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, an amino group, a trifluoromethyl group, a trifluoromethoxy group, and a trifluoromethylthio group; however, R 3 When R is a substituted or unsubstituted phenyl group, 5 Not a hydrogen atom; R 6 It may be a hydroxyl, carboxyl, nitro, cyano, fluorine atom, chlorine atom, bromine atom, iodine atom or amino group, or may contain at least one of the following: a saturated hydrocarbon group having 1 to 20 carbon atoms, a saturated hydrocarbon oxy group having 1 to 20 carbon atoms, a saturated hydrocarbon carbonyl oxy group having 2 to 20 carbon atoms, a saturated hydrocarbon oxy carbonyl group having 2 to 20 carbon atoms, or a saturated hydrocarbon sulfonyl oxy group having 1 to 4 carbon atoms; R 7 It can also contain hydrocarbon groups with 1 to 20 carbon atoms that are heteroatoms; when s = 1, there are 2 R groups. 7 They can be the same or different from each other, and they can also bond to each other and form a ring together with the sulfur atoms they are bonded to.

2. The corrosion resist material according to claim 1, wherein, The repeating unit 'a' is represented by either (a1) or (a2); In the formula, R A Each can be independently a hydrogen atom or a methyl group; X 1 It is a single bond or an ester bond; X 2 For single key, -X 21 -C(=O)-O- or -X 21 -O-;X 21 It is a hydrocarbon group with 1 to 12 carbon atoms, a phenylene group, or a group with 7 to 18 carbon atoms obtained by combining them, and may also contain a carbonyl group, an ester bond, an ether bond, an iodine atom, or a bromine atom; X 3 It is a single bond, methylene, or ethylene; X 4 Single bond, methylene, ethylene, phenylene, methylphenylene, dimethylphenylene, fluorinated phenylene, phenylene substituted with trifluoromethyl, -OX 41 -、-C(=O)-OX 41 -or-C(=O)-NH-X 41 -;X 41 It is an aliphatic alkylene group, phenylene, methylphenylene, dimethylphenylene, fluorinated phenylene, or phenylene substituted with trifluoromethyl, having 1 to 6 carbon atoms, and may also contain carbonyl groups, ester bonds, ether bonds, hydroxyl groups, or halogen atoms; Rf 1 ~Rf 4 Each of the following is independently a hydrogen atom, a fluorine atom, or a trifluoromethyl group, but at least one of them is a fluorine atom or a trifluoromethyl group; also, Rf 1 and Rf 2 They can also combine to form carbonyl groups; M + The sulfonium cation is represented by formula (1).

3. The corrosion resist material according to claim 1 further contains an organic solvent.

4. The corrosion resist material according to claim 1, wherein, The base polymer may further contain repeating units represented by formula (b1) or formula (b2); In the formula, R A Each can be independently a hydrogen atom or a methyl group; Y 1 It is a single bond, a phenylene or naphthylene group, or contains a linking group with 1 to 12 carbon atoms selected from ester bonds, ether bonds and lactone rings; Y 2 It is a single bond or an ester bond; Y 3 It can be a single bond, an ether bond, or an ester bond; R 11 and R 12 Each is an acid-labile group; R 13 It can be a fluorine atom, trifluoromethyl, cyano, a saturated hydrocarbon group with 1 to 6 carbon atoms, a saturated hydrocarbon oxy group with 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl group with 2 to 7 carbon atoms, a saturated hydrocarbon carbonyl oxy group with 2 to 7 carbon atoms, or a saturated hydrocarbon oxy carbonyl group with 2 to 7 carbon atoms. R 14 It is a single bond or an alkyl diene with 1 to 6 carbon atoms, and part of the -CH2- of the alkyl diene may also be replaced by an ether bond or an ester bond; a is 1 or 2; b is an integer from 0 to 4; however, 1 ≤ a + b ≤ 5.

5. The resist material according to claim 4 is a chemically amplified positive resist material.

6. The resist material according to claim 1 further contains a surfactant.

7. A method for forming a pattern, comprising the following steps: A resist film is formed on the substrate using the resist material according to any one of claims 1 to 6. The resist film was exposed to high-energy rays, and The exposed resist film was developed using a developer.

8. The pattern forming method according to claim 7, wherein, The high-energy rays are KrF excimer lasers, ArF excimer lasers, electron beams, or extreme ultraviolet rays with wavelengths of 3–15 nm.

Images