Resist material and pattern forming method

Abstract

The present invention relates to a resist material and a pattern forming method. The present invention provides a resist material which is high in sensitivity and improved in LWR and CDU, and a pattern forming method using the same. The means for solving the problem is a resist material containing an acid generator comprising a sulfonium salt 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 Sensor), 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 the next-generation 3nm node and the 2nm node after that, with Belgium's IMEC demonstrating 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 properties, to further improve the solubility contrast. Patent documents 3 and 4 disclose resist materials containing sulfonium salts with tertiary ester-type acid-instable groups in the cationic portion, while patent documents 5 and 6 disclose resist materials containing sulfonium salts with acid-instable groups in the anionic portion. 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 Literature]

[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] [Patent Document 6] International Publication No. 2021 / 200056

[0017] [Non-patent literature]

[0018] [Non-Patent Literature 1] SPIE Vol.6520 65203L-1(2007) Summary of the Invention

[0019] [The problem that the invention aims to solve]

[0020] 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.

[0021] The present invention was made in view of the foregoing circumstances, and aims to provide a photoresist material, particularly in positive resist materials, that is highly sensitive and improves LWR and CDU, and a method for patterning using the photoresist material.

[0022] [Methods for solving the problem]

[0023] Through repeated and in-depth research in order to achieve the aforementioned objectives, the inventors discovered that a sulfonate salt containing a cationic moiety with a tertiary ester-type acid-unstable group having a triple bond exhibits excellent acid-induced desorption reactivity and high affinity for alkaline developing solutions. As a result, it can achieve high contrast and low swelling characteristics, thereby obtaining a sulfonate material with improved LWR and CDU, excellent resolution, and a wide process tolerance range, thus completing the present invention.

[0024] That is, the present invention provides the following resist material and pattern forming method.

[0025] 1. A corrosion resist material comprising: an acid generating agent containing a sulfite salt represented by formula (1).

[0026] [Chemistry 1]

[0027]

[0028] 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.

[0029] R 1 It can be a single bond, ether bond, thioether bond, or ester bond.

[0030] 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.

[0031] 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.

[0032] 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.

[0033] 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.

[0034] 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.

[0035] X - It is a non-nucleophilic relative ion.

[0036] 2. The resist material as described in 1, wherein the aforementioned non-nucleophilic relative ion is a sulfonic acid anion, an imide anion, or a methylation anion.

[0037] 3. As in 1. or 2., the resist materials contain organic solvents.

[0038] 4. The resist materials mentioned in any of 1 to 3 further contain a basic polymer.

[0039] 5. The resist material of any one of 1 to 4, wherein the aforementioned base polymer comprises a repeating unit represented by formula (a1) or a repeating unit represented by formula (a2).

[0040] [Chemistry 2]

[0041]

[0042] In the formula, R A Each can be a hydrogen atom or a methyl group, independently.

[0043] X 1 It is a single bond, a phenylene or naphthylene group, or a linking group containing at least one of the following: an ester bond, an ether bond, or a lactone ring, having 1 to 12 carbon atoms.

[0044] X 2 It consists of a single bond or an ester bond.

[0045] X 3 It can be a single bond, an ether bond, or an ester bond.

[0046] R 11 and R 12 Each is an acid-labile group.

[0047] 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.

[0048] 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.

[0049] a is 1 or 2. b is an integer from 0 to 4. However, 1 ≤ a + b ≤ 5.

[0050] 6. As in 5, the resist material is a chemically amplified positive resist material.

[0051] 7. The resist material of any one of 4. to 6., wherein the aforementioned base polymer comprises at least one repeating unit selected from the following formulas (f1) to (f3).

[0052] [Chemistry 3]

[0053]

[0054] In the formula, R A Each can be a hydrogen atom or a methyl group, independently.

[0055] Z 1 It is a single bond, an aliphatic hydrocarbon group having 1 to 6 carbon atoms, a phenylene group, a naphthylene group, or a group having 7 to 18 carbon atoms obtained by combining them, or -OZ. 11 -、-C(=O)-OZ 11 -or-C(=O)-NH-Z 11 -. Z11 It is an aliphatic alkylene group, phenylene group, naphthylene group or a combination thereof with 7 to 18 carbon atoms, and may also contain carbonyl groups, ester bonds, ether bonds or hydroxyl groups.

[0056] Z 2 It is a single bond or an ester bond.

[0057] Z 3 For single key, -Z 31 -C(=O)-O-、-Z 31 -O- or -Z 31 -OC(=O)-。 Z 31 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.

[0058] Z 4 It can be methylene, 2,2,2-trifluoro-1,1-ethanediyl, or carbonyl.

[0059] Z 5 Single bond, methylene, ethylene, phenylene, fluorinated phenylene, phenylene substituted with trifluoromethyl, -OZ 51 -、-C(=O)-OZ 51 -or-C(=O)-NH-Z 51 -. Z 51 It is an aliphatic alkylene group, phenylene, 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.

[0060] R 21 ~R 28 Each group consists independently of a halogen atom, or may contain heteroatoms, and is a hydrocarbon group with 1 to 20 carbon atoms. Also, R 23 and R 24 or R 26 and R 27 They can also bond to each other and form rings together with the sulfur atoms they are bonded to.

[0061] M - It is a non-nucleophilic relative ion.

[0062] 8. The resist materials mentioned in any of 1 to 7 contain surfactants.

[0063] 9. A method for forming a pattern, comprising the following steps:

[0064] A resist film is formed on the substrate using any of the resist materials described in 1. to 8.

[0065] The aforementioned resist film was exposed to high-energy radiation, and

[0066] The previously exposed resist film was developed using a developer.

[0067] 10. The pattern forming method as described in 9, 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.

[0068] [The effects of the invention]

[0069] Resist materials containing sulfonium salts represented by formula (1), when containing a base polymer containing acid-instable groups, not only improve the alkali dissolution rate by utilizing the polarity change caused by the acid-catalyzed reaction due to exposure, similar to known acid generators, but also, regarding the acid generator itself, its unexposed portion is insoluble in the developer, while through exposure, it generates carboxyl groups due to the generated acid, thus improving the alkali dissolution rate. Utilizing these properties, improved LWR and CDU resist materials can be constructed. Detailed Implementation

[0070] [Corrosion Resistance Materials]

[0071] The resist material of the present invention contains an acid generating agent comprising a sulfonium salt having a tertiary ester-type acid unstable group with a triple bond.

[0072] [Sumine salts with cations containing unstable tertiary ester-type acid groups with triple bonds]

[0073] The aforementioned sulfonium salt with a triple bonded tertiary ester-type acid unstable group is represented by the following formula (1).

[0074] [Chemistry 4]

[0075]

[0076] 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.

[0077] 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.

[0078] In equation (1), R 2It 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.

[0079] 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.

[0080] R 3 and R 4 The 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.

[0081] 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 3When R is a substituted or unsubstituted phenyl group, 5 It is not a hydrogen atom.

[0082] 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.

[0083] 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.

[0084] R 6 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.

[0085] 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.

[0086] 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.

[0087] 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.

[0088] 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.

[0089] Examples of aralkyl groups mentioned above include benzyl and phenethyl.

[0090] 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. The -CH2- group in a portion of 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, carboxyl groups, halogen atoms, cyano groups, amino groups, nitro groups, sulfonyl groups, sulfone groups, groups containing sulfonium salts, ether bonds, ester bonds, carbonyl groups, thioether bonds, sulfonyl groups, amide bonds, etc.

[0091] 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.

[0092] [Chemistry 5]

[0093]

[0094] In the formula, the dashed lines represent the atomic bonds of the aromatic ring in formula (1).

[0095] The base polymer and the aforementioned matte salt dissolve in the alkaline developer through a deprotection reaction catalyzed by acid-indestructible groups, exhibiting further high solubility contrast. This allows for further improvements in sensitivity and reduced LWR and CDU. Furthermore, by ensuring that the exposure required to improve the solubility of the base polymer due to the deprotection reaction is the same as the exposure required to dissolve the matte salt, contrast can be significantly enhanced.

[0096] When the acid-labile unstable groups of the base polymer and the aforementioned sulfonium salt have the same structure, the sulfonium salt located near the generated acid is more prone to deprotection. Even if deprotection occurs simultaneously, the sulfonium salt with a smaller molecular weight will dissolve in the alkaline developer at low exposure levels. Sulfonium salts substituted with known acid-labile unstable groups, having the same acid-labile unstable groups as the base polymer, exhibit lower improvement in solubility contrast due to the difference in deprotection reactivity between the base polymer and the sulfonium salt.

[0097] In this invention, to eliminate the difference in deprotection reactivity between the base polymer and the sulfonate, the acid-labile group of the sulfonate should preferably have a lower deprotection reactivity than the acid-labile group of the base polymer. For example, when it is an acid-labile group containing an aromatic group, the deprotection reactivity can be adjusted to be low by introducing electron-withdrawing groups such as halogen atoms, cyano groups, and nitro groups into the aromatic group.

[0098] The cations of the sulfonium salt represented by formula (1) can be listed below, but are not limited to these.

[0099] [Chemistry 6]

[0100]

[0101] [Chemistry 7]

[0102]

[0103] [Chemistry 8]

[0104]

[0105] [Chemistry 9]

[0106]

[0107] [Chemistry 10]

[0108]

[0109] [Chemistry 11]

[0110]

[0111] [Chemistry 12]

[0112]

[0113] [Chemistry 13]

[0114]

[0115] [Chemistry 14]

[0116]

[0117] [Chemistry 15]

[0118]

[0119] [Chemistry 16]

[0120]

[0121] [Chemistry 17]

[0122]

[0123] [Chemistry 18]

[0124]

[0125] [Chemistry 19]

[0126]

[0127] [Chemistry 20]

[0128]

[0129] [Chemistry 21]

[0130]

[0131] [Chemistry 22]

[0132]

[0133] [Chemistry 23]

[0134]

[0135] [Chemistry 24]

[0136]

[0137] [Chemistry 25]

[0138]

[0139] [Chemistry 26]

[0140]

[0141] [Chemistry 27]

[0142]

[0143] [Chemistry 28]

[0144]

[0145] [Chemistry 29]

[0146]

[0147] [Chemistry 30]

[0148]

[0149] [Chemistry 31]

[0150]

[0151] [Chemistry 32]

[0152]

[0153] [Chemistry 33]

[0154]

[0155] [Chemistry 34]

[0156]

[0157] [Chemistry 35]

[0158]

[0159] [Chemistry 36]

[0160]

[0161] [Chemistry 37]

[0162]

[0163] [Chemistry 38]

[0164]

[0165] [Chemistry 39]

[0166]

[0167] [Chemistry 40]

[0168]

[0169] [Chemistry 41]

[0170]

[0171] [Chemistry 42]

[0172]

[0173] [Chemistry 43]

[0174]

[0175] [Chemistry 44]

[0176]

[0177] [Chemistry 45]

[0178]

[0179] [Chemistry 46]

[0180]

[0181] [Chemistry 47]

[0182]

[0183] [Chemistry 48]

[0184]

[0185] [Chemistry 49]

[0186]

[0187] [Transformation 50]

[0188]

[0189] [Chemistry 51]

[0190]

[0191] [Chemistry 52]

[0192]

[0193] [Chemistry 53]

[0194]

[0195] [Chemistry 54]

[0196]

[0197] [Chemistry 55]

[0198]

[0199] [Chemistry 56]

[0200]

[0201] [Chemistry 57]

[0202]

[0203] [Chem.58]

[0204]

[0205] [Chemistry 59]

[0206]

[0207] [Transformation 60]

[0208]

[0209] [Chemistry 61]

[0210]

[0211] [Chemistry 62]

[0212]

[0213] [Chemistry 63]

[0214]

[0215] [Chemistry 64]

[0216]

[0217] [Chemistry 65]

[0218]

[0219] [Chemistry 66]

[0220]

[0221] [Chemistry 67]

[0222]

[0223] [Chemistry 68]

[0224]

[0225] [Chemistry 69]

[0226]

[0227] In equation (1), X -These are non-nucleophilic relative ions. Examples of such non-nucleophilic relative ions include: halide ions such as chloride ions and bromide ions; fluoroalkyl sulfonate ions such as trifluoromethanesulfonate ions, 1,1,1-trifluoroethanesulfonate ions, and nonafluorobutanesulfonate ions; aryl sulfonate ions such as toluenesulfonate ions, benzenesulfonate ions, 4-fluorobenzenesulfonate ions, and 1,2,3,4,5-pentafluorobenzenesulfonate ions; alkyl sulfonate ions such as methanesulfonate ions and butanesulfonate ions; imide ions such as bis(trifluoromethylsulfonyl)imide ions, bis(perfluoroethylsulfonyl)imide ions, and bis(perfluorobutylsulfonyl)imide ions; and methylate ions such as tri(trifluoromethylsulfonyl)methylide ions and tri(perfluoroethylsulfonyl)methylide ions.

[0228] Other examples of the aforementioned non-nucleophilic relative ions can be listed as anions selected from formulas (1A) to (1D).

[0229] [Chemistry 70]

[0230]

[0231] In equation (1A), R fa It is a hydrocarbon group with 1 to 40 carbon atoms, which may contain fluorine atoms or heteroatoms. The aforementioned hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be listed below: and the examples shown later are R in formula (1A'). fa1 The same applies to hydrocarbon groups.

[0232] The anion represented by formula (1A) should preferably be represented by formula (1A').

[0233] [Chemistry 71]

[0234]

[0235] In equation (1A'), R HF It can be a hydrogen atom or a trifluoromethyl group, preferably a trifluoromethyl group. R fa1 The hydrocarbon group may contain heteroatoms and has 1 to 38 carbon atoms. The aforementioned heteroatoms are preferably oxygen, nitrogen, sulfur, or halogen atoms, with oxygen atoms being more preferred. Considering the need for high resolution in the formation of fine patterns, hydrocarbon groups with 6 to 30 carbon atoms are particularly preferred.

[0236] R fa1The hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples include: alkyl groups with 1 to 38 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, neopentyl, hexyl, heptyl, 2-ethylhexyl, nonyl, undecyl, tridecyl, pentadecyl, heptadecanyl, and eicosyl; cyclic saturated hydrocarbon groups with 3 to 38 carbon atoms, such as cyclopentyl, cyclohexyl, 1-adamantyl, 2-adamantyl, 1-adamantylmethyl, norcamphenyl, norcamphenylmethyl, tricyclodecyl, tetracyclododecyl, tetracyclododecylmethyl, and dicyclohexylmethyl; unsaturated aliphatic hydrocarbon groups with 2 to 38 carbon atoms, such as allyl and 3-cyclohexenyl; aryl groups with 6 to 38 carbon atoms, such as phenyl, 1-naphthyl, 2-naphthyl, and 9-fluorenyl; aralkyl groups with 7 to 38 carbon atoms, such as benzyl and diphenylmethyl; and groups obtained by combining them.

[0237] Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group can be replaced by groups containing heteroatoms such as oxygen, sulfur, nitrogen, or halogen atoms. Similarly, some of the -CH2- group in the aforementioned hydrocarbon group can be replaced by groups containing heteroatoms such as oxygen, sulfur, or nitrogen atoms. As a result, it may contain hydroxyl, fluorine, chlorine, bromine, iodine, cyano, nitro, carbonyl, ether, ester, sulfonate, carbonate, lactone ring, sulopentalide ring, carboxylic anhydride (-C(=O)-OC(=O)-), haloalkyl, etc. Examples of hydrocarbon groups containing heteroatoms include: tetrahydrofuranyl, methoxymethyl, ethoxymethyl, methylthiomethyl, acetamidemethyl, trifluoroethyl, (2-methoxyethoxy)methyl, acetoxymethyl, 2-carboxy-1-cyclohexyl, 2-oxopropyl, 4-oxo-1-adamantyl, 3-oxocyclohexyl, etc.

[0238] The anions represented by formula (1A) can be listed below, but are not limited to. Additionally, in the following formula, Ac represents an acetyl group.

[0239] [Chemistry 72]

[0240]

[0241] [Chemistry 73]

[0242]

[0243] [Chemistry 74]

[0244]

[0245] [Chemistry 75]

[0246]

[0247] In equation (1B), R fb1and R fb2 Each hydrocarbon group consists independently of a fluorine atom or may contain heteroatoms and has 1 to 40 carbon atoms. 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 (1A'). fa1 The same applies to hydrocarbon groups. R fb1 and R fb2 It should preferably be a fluorine atom or a straight-chain fluorinated alkyl group having 1 to 4 carbon atoms. Also, R fb1 With R fb2 They can also bond to each other and to the groups they are bonded to (-CF2-SO2-N). - -SO2-CF2-) together form a ring, at which point R fb1 With R fb2 The groups formed by mutual bonding should preferably be fluorinated ethylidene or fluorinated propyleneide.

[0248] In equation (1C), R fc1 R fc2 and R fc3 Each hydrocarbon group consists independently of a fluorine atom or may contain heteroatoms and has 1 to 40 carbon atoms. 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 (1A'). fa1 The same applies to hydrocarbon groups. R fc1 R fc2 and R fc3 It should preferably be a fluorine atom or a straight-chain fluorinated alkyl group having 1 to 4 carbon atoms. Also, R fc1 With R fc2 They can also bond to each other and to the groups they are bonded to (-CF2-SO2-C). - -SO2-CF2-) together form a ring, at which point R fc1 With R fc2 The groups formed by mutual bonding should preferably be fluorinated ethylidene or fluorinated propyleneide.

[0249] In equation (1D), R fd It can be a hydrocarbon group with 1 to 40 carbon atoms, which may also contain heteroatoms. The aforementioned hydrocarbon group can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples can be listed as follows: and R is shown as an example in formula (1A'). fa1 The same applies to hydrocarbon groups.

[0250] Anions represented by formula (1D) can be listed below, but are not limited to these.

[0251] [Chemistry 76]

[0252]

[0253] [Chemistry 77]

[0254]

[0255] The examples of the aforementioned non-nucleophilic relative ions can be further illustrated by anions having aromatic rings substituted with iodine or bromine atoms. Such anions can be represented by the following formula (1E).

[0256] [Chemistry 78]

[0257]

[0258] In equation (1E), x is an integer satisfying 1 ≤ x ≤ 3. y and z are integers satisfying 1 ≤ y ≤ 5, 0 ≤ z ≤ 3, and 1 ≤ y + z ≤ 5. y should preferably be an integer satisfying 1 ≤ y ≤ 3, preferably 2 or 3. z should preferably be an integer satisfying 0 ≤ z ≤ 2.

[0259] In equation (1E), X BI When the atoms are iodine or bromine atoms, and x and / or y are 2 or more, they can be the same or different.

[0260] In equation (1E), L 1 It is a saturated hydrocarbon group with 1 to 6 carbon atoms, consisting of a single bond, ether bond, or ester bond, or may also contain ether or ester bonds. The aforementioned saturated hydrocarbon group may be linear, branched, or cyclic.

[0261] In equation (1E), L 2 When x is 1, it is a single bond or a divalent linker with 1 to 20 carbon atoms; when x is 2 or 3, it is a (x+1) valent linker with 1 to 20 carbon atoms. This linker may also contain oxygen, sulfur, or nitrogen atoms.

[0262] In equation (1E), R 8 The carbon group may be a hydroxyl, carboxyl, fluorine, chlorine, bromine, or amino group, or may contain a fluorine, chlorine, bromine, hydroxyl, amino, or ether bond, and may be a hydrocarbon group having 1 to 20 carbon atoms, a hydrocarbon oxy group having 1 to 20 carbon atoms, a hydrocarbon carbonyl group having 2 to 20 carbon atoms, a hydrocarbon oxycarbonyl group having 2 to 10 carbon atoms, a hydrocarbon carbonyl oxy group having 2 to 20 carbon atoms, or a hydrocarbon sulfonyl oxy group having 1 to 20 carbon atoms, or -N(R 8A (R) 8B ), -N(R 8C )-C(=O)-R 8D or -N(R) 8C )-C(=O)-OR 8D R 8A and R 8B Each can be independently a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms. R 8CIt is a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms, and may also contain a halogen atom, a hydroxyl group, a saturated hydrocarbon group having 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl group having 2 to 6 carbon atoms, or a saturated hydrocarbon carbonyl group having 2 to 6 carbon atoms. R 8D It is an aliphatic hydrocarbon group having 1 to 16 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 15 carbon atoms, and may also contain a halogen atom, a hydroxyl group, a saturated hydrocarbon oxy group having 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl group having 2 to 6 carbon atoms, or a saturated hydrocarbon carbonyl oxy group having 2 to 6 carbon atoms. The aforementioned aliphatic hydrocarbon group may be saturated or unsaturated, and may be any of the following: straight-chain, branched, or cyclic. The aforementioned hydrocarbon group, hydrocarbon oxy group, hydrocarbon carbonyl group, hydrocarbon oxycarbonyl group, hydrocarbon carbonyl oxy group, and hydrocarbon sulfonyl oxy group may be any of the following: straight-chain, branched, or cyclic. When x and / or z are 2 or more, each R 8 They can be the same or different.

[0263] Among them, R 8 It is advisable to use hydroxyl groups, -N(R) 8C )-C(=O)-R 8D -N(R) 8C )-C(=O)-OR 8D Fluorine atoms, chlorine atoms, bromine atoms, methyl groups, methoxy groups, etc.

[0264] In equation (1E), Rf 1 ~Rf 4 Each of these 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 With Rf 2 They can also combine to form carbonyl groups. Rf 3 and Rf 4 All of them are fluorine atoms, which is of excellent quality.

[0265] The anions represented by formula (1E) can be listed below, but are not limited to these. Additionally, in the following formula, X... BI Same as above.

[0266] [Chemistry 79]

[0267]

[0268] [Chemistry 80]

[0269]

[0270] [Chemistry 81]

[0271]

[0272] [Chemistry 82]

[0273]

[0274] [Chemistry 83]

[0275]

[0276] [Chemistry 84]

[0277]

[0278] [Chemistry 85]

[0279]

[0280] [Chemistry 86]

[0281]

[0282] [Chemistry 87]

[0283]

[0284] [Chemistry 88]

[0285]

[0286] [Chemistry 89]

[0287]

[0288] [Chemistry 90]

[0289]

[0290] [Chemistry 91]

[0291]

[0292] [Chemistry 92]

[0293]

[0294] [Chemistry 93]

[0295]

[0296] [Chemistry 94]

[0297]

[0298] [Chemistry 95]

[0299]

[0300] [Chemistry 96]

[0301]

[0302] [Chemistry 97]

[0303]

[0304] [Chem. 98]

[0305]

[0306] [Chemistry 99]

[0307]

[0308] [Chemistry 100]

[0309]

[0310] [Chemistry 101]

[0311]

[0312] The aforementioned non-nucleophilic relative ions may also include the fluorobenzenesulfonic acid anion bonded to an aromatic group containing an iodine atom as described in Japanese Patent No. 6648726, the anion with a mechanism of decomposition due to acid as described in International Publication No. 2021 / 200056 or Japanese Patent Application Publication No. 2021-070692, the anion with a cyclic ether group as described in Japanese Patent Application Publication No. 2018-180525 or Japanese Patent Application Publication No. 2021-35935, and the anion as described in Japanese Patent Application Publication No. 2018-092159.

[0313] The aforementioned non-nucleophilic relative ions may also be the bulky benzenesulfonic acid derivative anions without fluorine atoms described in Japanese Patent Application Publication No. 2006-276759, Japanese Patent Application Publication No. 2015-117200, Japanese Patent Application Publication No. 2016-65016 and Japanese Patent Application Publication No. 2019-202974, or the benzenesulfonic acid anions or alkylsulfonic acid anions bonded to an aromatic group containing iodine atoms without fluorine atoms described in Japanese Patent No. 6645464.

[0314] The aforementioned non-nucleophilic relative ions may also be the anions of disulfonic acid described in Japanese Patent Application Publication No. 2015-206932, the anions of sulfonic acid on one side and sulfonamide or sulfonylimide on the other side as described in International Publication No. 2020 / 158366, and the anions of sulfonic acid on one side and carboxylic acid on the other side as described in Japanese Patent Application Publication No. 2015-024989.

[0315] The synthesis methods of the sulfonium salt represented by formula (1) can be listed as follows: the method of ion exchange between the weak acid salt of the aforementioned sulfonium cation and the ammonium salt having the aforementioned non-nucleophilic relative ion.

[0316] In the resist material of the present invention, the content of sulfonium salt represented by formula (1) relative to 100 parts by mass of the base polymer described later is preferably 0.01 to 1,000 parts by mass, and more preferably 0.05 to 500 parts by mass, taking into account sensitivity and acid diffusion inhibition effect.

[0317] [Basic Polymers]

[0318] When the base polymer contained in the resist material of the present invention is a positive resist material, it contains repeating units containing acid-instable groups. The repeating units containing acid-instable groups are preferably repeating units represented by the following formula (a1) (hereinafter also referred to as repeating unit a1) or repeating units represented by the following formula (a2) (hereinafter also referred to as repeating unit a2).

[0319] [Chemistry 102]

[0320]

[0321] 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, a phenylene or naphthylene group, or a linking group containing at least one of the following: an ester bond, an ether bond, or a lactone ring, having 1 to 12 carbon atoms. X 2 It is a single bond or an ester bond. X 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 having 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.

[0322] Monomers providing repeating unit a1 can be listed below, but are not limited to. Additionally, in the following formula, R... A and R 11 Same as above.

[0323] [Chemistry 103]

[0324]

[0325] Monomers providing repeating unit a2 can be listed below, but are not limited to. Additionally, in the following formula, R... A and R 12 Same as above.

[0326] [Chemistry 104]

[0327]

[0328] In equations (a1) and (a2), 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.

[0329] For representative purposes, the aforementioned unstable acid groups can be represented by the following formulas (L-1) to (L-3).

[0330] [Chemistry 105]

[0331]

[0332] In the formula, the dashed lines represent atomic bonds.

[0333] 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 may be saturated or unsaturated, and may be linear, branched, or cyclic. Preferably, the aforementioned hydrocarbon groups are saturated hydrocarbon groups with 1 to 40 carbon atoms, and saturated hydrocarbon groups with 1 to 20 carbon atoms are even more preferred.

[0334] In equation (L-1), c is an integer from 0 to 10, and preferably an integer from 1 to 5.

[0335] In equation (L-2), R L3 and R L4 Each 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.

[0336] In equation (L-3), R L5 R L6 and R L7Each 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 are bonded 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.

[0337] The aforementioned basic polymer may also contain repeating unit b, which has a phenolic hydroxyl group as a binding group. Monomers providing repeating unit b can be listed below, but are not limited to these. Additionally, in the following formula, R... A Same as above.

[0338] [Chemistry 106]

[0339]

[0340] The aforementioned basic polymer may also contain repeating unit c 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 unit c are listed below, but are not limited thereto. Additionally, in the following formula, R... A Same as above.

[0341] [Chemistry 107]

[0342]

[0343] [Chemistry 108]

[0344]

[0345] [Chemistry 109]

[0346]

[0347] [Chemical 110]

[0348]

[0349] [Chemistry 111]

[0350]

[0351] [Chemistry 112]

[0352]

[0353] [Chemistry 113]

[0354]

[0355] [Chemistry 114]

[0356]

[0357] The aforementioned base polymer may also contain repeating units d derived from indene, benzofuran, benzothiophene, acenaphthene, crromone, coumarin, norcamphediene, or derivatives thereof. Monomers providing repeating units d may be listed below, but are not limited thereto.

[0358] [Chemistry 115]

[0359]

[0360] The aforementioned base polymer may also contain repeating units e derived from styrene, ethylene naphthalene, ethylene anthracene, ethylene pyrene, methylene dihydroindene, ethylene pyridine, or ethylene carbazole.

[0361] The aforementioned basic polymer may also contain repeating units f from onium salts containing polymerizable unsaturated bonds. Ideal repeating units f can be listed as follows: repeating units represented by formula (f1) (hereinafter also referred to as repeating unit f1), repeating units represented by formula (f2) (hereinafter also referred to as repeating unit f2), and repeating units represented by formula (f3) (hereinafter also referred to as repeating unit f3). Furthermore, repeating units f1 to f3 can be used individually or in combination of two or more.

[0362] [Chemistry 116]

[0363]

[0364] In equations (f1) to (f3), R A Each can be independently a hydrogen atom or a methyl group. Z 1 It is a single bond, an aliphatic hydrocarbon group having 1 to 6 carbon atoms, a phenylene group, a naphthylene group, or a group having 7 to 18 carbon atoms obtained by combining them, or -OZ. 11 -、-C(=O)-OZ 11 -or-C(=O)-NH-Z 11 -. Z 11 It is an aliphatic hydrocarbon group, phenylene group, naphthylene group, or a combination thereof with 7 to 18 carbon atoms, having 1 to 6 carbon atoms, and may also contain a carbonyl group, ester bond, ether bond, or hydroxyl group. 2 It is a single bond or an ester bond. Z 3 For single key, -Z 31 -C(=O)-O-、-Z 31 -O- or -Z 31 -OC(=O)-。 Z 31It 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. 4 It is methylene, 2,2,2-trifluoro-1,1-ethanediyl, or carbonyl. 5 Single bond, methylene, ethylene, phenylene, fluorinated phenylene, phenylene substituted with trifluoromethyl, -OZ 51 -、-C(=O)-OZ 51 -or-C(=O)-NH-Z 51 -. Z 51 It is an aliphatic alkylene group, phenylene, 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.

[0365] In equations (f1) to (f3), R 21 ~R 28 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 hydrocarbon groups. Furthermore, some or all of the hydrogen atoms in the aforementioned hydrocarbon group can be replaced by groups containing heteroatoms such as oxygen, sulfur, nitrogen, or halogen atoms. Similarly, part of the -CH2- group in the aforementioned hydrocarbon group can be replaced by groups containing heteroatoms such as oxygen, sulfur, or nitrogen atoms. As a result, it may contain hydroxyl, fluorine, chlorine, bromine, iodine, cyano, nitro, carbonyl, ether, ester, sulfonate, carbonate, lactone ring, sulfonyl lactone ring, carboxylic anhydride (-C(=O)-OC(=O)-), haloalkyl, etc. Also, R 23 and R 24 or R 26 and R 27 They can also bond to each other and form rings together with the sulfur atoms they are bonded to. In this case, the aforementioned rings can be exemplified as two R atoms in the description of equation (1). 7 They can also bond to each other and form rings together with the sulfur atoms they are bonded to.

[0366] In equation (f1), M -These are non-nucleophilic relative ions. Examples of such non-nucleophilic relative ions include: halide ions such as chloride ions and bromide ions; fluoroalkyl sulfonate ions such as trifluoromethanesulfonate ions, 1,1,1-trifluoroethanesulfonate ions, and nonafluorobutanesulfonate ions; aryl sulfonate ions such as toluenesulfonate ions, benzenesulfonate ions, 4-fluorobenzenesulfonate ions, and 1,2,3,4,5-pentafluorobenzenesulfonate ions; alkyl sulfonate ions such as methanesulfonate ions and butanesulfonate ions; imide ions such as bis(trifluoromethylsulfonyl)imide ions, bis(perfluoroethylsulfonyl)imide ions, and bis(perfluorobutylsulfonyl)imide ions; and methylate ions such as tri(trifluoromethylsulfonyl)methylide ions and tri(perfluoroethylsulfonyl)methylide ions.

[0367] Also, M - The non-nucleophilic relative ions can also be represented by any of the anions in formulas (1A) to (1E).

[0368] The cations that provide the repeating unit f1 can be listed below, but are not limited to. Additionally, in the following formula, R... A Same as above.

[0369] [Chemistry 117]

[0370]

[0371] Specific examples of cations that provide repeating units f2 or f3 include the sulfonium cation described in Japanese Patent Application Publication No. 2017-219836.

[0372] The anions of the monomers providing the repeating unit f2 can be listed below, but are not limited to. Additionally, in the following formula, R... A Same as above.

[0373] [Chemistry 118]

[0374]

[0375] [Chemistry 119]

[0376]

[0377] [Chemistry 120]

[0378]

[0379] [Chemistry 121]

[0380]

[0381] [Chemistry 122]

[0382]

[0383] [Chemistry 123]

[0384]

[0385] [Chemistry 124]

[0386]

[0387] [Chemistry 125]

[0388]

[0389] [Chemistry 126]

[0390]

[0391] [Chemistry 127]

[0392]

[0393] [Chemistry 128]

[0394]

[0395] [Chemistry 129]

[0396]

[0397] Anions of monomers providing repeating unit f3 can be listed below, but are not limited to. Additionally, in the following formula, R... A Same as above.

[0398] [Chemistry 130]

[0399]

[0400] By bonding the acid generator to the polymer backbone, acid diffusion can be reduced, and the resolution loss caused by acid diffusion blurring can be prevented. Furthermore, uniform dispersion of the acid generator improves LWR and CDU.

[0401] In the base polymer for a positive resist material, it is necessary to have the repeating unit a1 or a2 containing an acid-labile group. At this time, the content ratios of the repeating units a1, a2, b, c, d, e, and f should be 0 ≤ a1 < 1.0, 0 ≤ a2 < 1.0, 0 < a1 + a2 < 1.0, 0 ≤ b ≤ 0.9, 0 ≤ c ≤ 0.9, 0 ≤ d ≤ 0.8, 0 ≤ e ≤ 0.8, and 0 ≤ f ≤ 0.5. It is more preferable that 0 ≤ a1 ≤ 0.9, 0 ≤ a2 ≤ 0.9, 0.1 ≤ a1 + a2 ≤ 0.9, 0 ≤ b ≤ 0.8, 0 ≤ c ≤ 0.8, 0 ≤ d ≤ 0.7, 0 ≤ e ≤ 0.7, and 0 ≤ f ≤ 0.4. It is even more preferable that 0 ≤ a1 ≤ 0.8, 0 ≤ a2 ≤ 0.8, 0.1 ≤ a1 + a2 ≤ 0.8, 0 ≤ b ≤ 0.75, 0 ≤ c ≤ 0.75, 0 ≤ d ≤ 0.6, 0 ≤ e ≤ 0.6, and 0 ≤ f ≤ 0.3. In addition, when the repeating unit f is at least one selected from the repeating units f1 to f3, f = f1 + f2 + f3. Also, a1 + a2 + b + c + d + e + f = 1.0.

[0402] On the other hand, in the base polymer for a negative resist material, an acid-labile group is not necessarily required. Examples of such a base polymer include those containing the repeating unit b, and optionally further containing the repeating units c, d, e, and / or f. The content ratios of these repeating units should be 0 < b ≤ 1.0, 0 ≤ c ≤ 0.9, 0 ≤ d ≤ 0.8, 0 ≤ e ≤ 0.8, and 0 ≤ f ≤ 0.5. It is more preferable that 0.2 ≤ b ≤ 1.0, 0 ≤ c ≤ 0.8, 0 ≤ d ≤ 0.7, 0 ≤ e ≤ 0.7, and 0 ≤ f ≤ 0.4. It is even more preferable that 0.3 ≤ b ≤ 1.0, 0 ≤ c ≤ 0.75, 0 ≤ d ≤ 0.6, 0 ≤ e ≤ 0.6, and 0 ≤ f ≤ 0.3. In addition, when the repeating unit f is at least one selected from the repeating units f1 to f3, f = f1 + f2 + f3. Also, b + c + d + e + f = 1.0.

[0403] When synthesizing the aforementioned base polymer, for example, monomers providing the aforementioned repeating units are added with a radical polymerization initiator in an organic solvent and then heated to carry out polymerization.

[0404] Examples of the organic solvent used in the polymerization include toluene, benzene, tetrahydrofuran (THF), diethyl ether, dioxane, etc. Examples of the polymerization initiator 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 polymerization should be preferably 50 to 80 °C. The reaction time should be preferably 2 to 100 hours, and more preferably 5 to 20 hours.

[0405] When copolymerizing monomers containing hydroxyl groups, the hydroxyl groups can be replaced with acetal groups such as ethoxy-ethoxy, which are easily deprotected by acids, before polymerization, and deprotection can be carried out using weak acids and water after polymerization. Alternatively, they can be replaced with acetyl, formyl, trimethylacetyl, etc., before polymerization, and alkaline hydrolysis can be carried out after polymerization.

[0406] When copolymerizing hydroxystyrene and hydroxyvinylnaphthalene, hydroxystyrene and hydroxyvinylnaphthalene can be replaced with acetoxystyrene and acetoxyvinylnaphthalene, and the aforementioned alkaline hydrolysis can be used after polymerization to deprotect the acetoxy group to obtain hydroxystyrene and hydroxyvinylnaphthalene.

[0407] The alkali used in alkaline hydrolysis can be ammonia, triethylamine, etc. Furthermore, the reaction temperature should preferably be -20 to 100℃, with 0 to 60℃ being more ideal. The reaction time should preferably be 0.2 to 100 hours, with 0.5 to 20 hours being more ideal.

[0408] 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.

[0409] 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.

[0410] The aforementioned basic polymer may also include two or more polymers with different composition ratios, Mw, and Mw / Mn.

[0411] [Organic solvents]

[0412] 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.

[0413] 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.

[0414] [Quenching Agent]

[0415] The resist material of the present invention may also contain a quencher. Furthermore, a quencher refers to a compound that can prevent diffusion to unexposed areas by capturing acid generated from an acid-generating agent in the resist material.

[0416] 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.

[0417] 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.

[0418] 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).

[0419] [Chemistry 131]

[0420]

[0421] 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.

[0422] R 101 The 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.

[0423] Furthermore, the hydrogen atoms in a portion of the aforementioned hydrocarbon group can also be replaced by groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms, and the carbon atoms in a portion of 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 also 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; and aryl-side alkyl groups such as 2-phenyl-2-oxoethyl, 2-(1-naphthyl)-2-oxoethyl, and 2-(2-naphthyl)-2-oxoethyl.

[0424] 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 101 The 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.

[0425] 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.

[0426] 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.

[0427] Alternatively, the sulfonium salt of a carboxylic acid containing an iodinated benzene ring, represented by formula (5), can ideally be used as a quencher.

[0428] [Chemistry 132]

[0429]

[0430] In equation (5), R 201The hydroxyl, fluorine, chlorine, bromine, amino, nitro, cyano, or partially or completely hydrogen atoms may be replaced by halogen atoms, and may be saturated hydrocarbon groups with 1 to 6 carbon atoms, saturated hydrocarbon oxy groups with 1 to 6 carbon atoms, saturated hydrocarbon carbonyl oxy groups with 2 to 6 carbon atoms, or saturated hydrocarbon sulfonyl oxy groups with 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.

[0431] 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.

[0432] 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, sulfone, or sulfonate-containing groups, and some of the carbon atoms 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.

[0433] 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.

[0434] 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.

[0435] 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.

[0436] 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.

[0437] [Other ingredients]

[0438] In addition to the aforementioned components, the resist material of the present invention may also contain acid generating agents other than the sulfonium salt represented by formula (1) (hereinafter referred to as other acid generating agents), surfactants, dissolution inhibitors, crosslinking agents, water repellency improvers, acetylene alcohols, etc.

[0439] 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 to be an acid generator that produces sulfonic acid, imine, or methyl acid. Ideal photoacid generators include: sulfonium salts, sulfonium salts, sulfonyl diazomethanes, N-sulfonyloxyimides, oxime-O-sulfonate type acid generators, etc. Specific examples of acid generators are described 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. When the resist material of the present invention contains other acid generators, 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.

[0440] 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.

[0441] 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.

[0442] 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.

[0443] On the other hand, when the resist material of the present invention is negative, a negative pattern can be obtained by adding a crosslinking agent, which reduces the dissolution rate of the exposed portion. Examples of such crosslinking agents include epoxy compounds substituted with at least one group selected from hydroxymethyl, alkoxymethyl, and acyloxymethyl groups; melamine compounds; guanidine compounds; glycourea compounds or urea compounds; isocyanate compounds; azide compounds; and compounds containing alkenyloxy groups or other double bonds. These can be used as additives or introduced into the polymer side chains as dangling groups. Furthermore, hydroxyl-containing compounds can also be used as crosslinking agents.

[0444] Examples of the aforementioned epoxy compounds include: tris(2,3-epoxypropyl)isocyanurate, trimethylolpropane triepoxypropyl ether, trimethylolpropane triepoxypropyl ether, triethylolethane triepoxypropyl ether, etc.

[0445] Examples of the aforementioned melamine compounds include: hexahydroxymethyl melamine, hexamethoxymethyl melamine, compounds of hexahydroxymethyl melamine in which 1 to 6 hydroxymethyl groups are methoxymethylated, or mixtures thereof, hexamethoxyethyl melamine, hexaacyloxymethyl melamine, compounds of hexahydroxymethyl melamine in which 1 to 6 hydroxymethyl groups are acyloxymethylated, or mixtures thereof, etc.

[0446] Examples of the aforementioned guanidine compounds include: tetrahydroxymethylguanidine, tetramethoxymethylguanidine, compounds of tetrahydroxymethylguanidine with 1 to 4 hydroxymethyl groups methoxymethylated, or mixtures thereof, tetramethoxyethylguanidine, tetraacyloxyguanidine, compounds of tetrahydroxymethylguanidine with 1 to 4 hydroxymethyl groups acyloxymethylated, or mixtures thereof, etc.

[0447] Examples of the aforementioned urea compounds include: tetrahydroxymethylurea, tetramethoxyurea, tetramethoxymethylurea, compounds in which 1 to 4 hydroxymethyl groups are methoxymethylated, or mixtures thereof, compounds in which 1 to 4 hydroxymethyl groups are acylmethylated, or mixtures thereof. Examples of urea compounds include: tetrahydroxymethylurea, tetramethoxymethylurea, compounds in which 1 to 4 hydroxymethyl groups are methoxymethylated, or mixtures thereof, tetramethoxyethylurea, etc.

[0448] Examples of the aforementioned isocyanate compounds include: toluene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, cyclohexane diisocyanate, etc.

[0449] Examples of the aforementioned azide compounds include: 1,1'-biphenyl-4,4'-bisazide, 4,4'-methylene bisazide, and 4,4'-oxy bisazide.

[0450] Examples of compounds containing alkenyloxy groups include: ethylene glycol divinyl ether, triethylene glycol divinyl ether, 1,2-propanediol divinyl ether, 1,4-butanediol divinyl ether, tetramethylenediol divinyl ether, neopentyl glycol divinyl ether, trimethylolpropane trivinyl ether, hexanediol divinyl ether, 1,4-cyclohexanediol divinyl ether, neopentyltetraethylenediol trivinyl ether, neopentyltetraethylenediol tetravinyl ether, sorbitol tetravinyl ether, sorbitol pentavinyl ether, trimethylolpropane trivinyl ether, etc.

[0451] When the resist material of the present invention is negative and contains the aforementioned crosslinking agent, its content relative to 100 parts by weight of the base polymer is preferably 0.1 to 50 parts by weight, and more preferably 1 to 40 parts by weight. The aforementioned crosslinking agent may be used alone or in combination of two or more.

[0452] 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 ammonium 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.

[0453] 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.

[0454] 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 suppresses 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 polar gel and metal ion adsorption capacity of membranes such as nylon, polyurethane, polycarbonate, and polyimide. However, surface modification with polar functional groups can improve the adsorption capacity of 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.

[0455] 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.

[0456] Multiple filters can be connected together during filtration. The membranes of the multiple filters can be of the same type and different diameters. Filtration can be carried out in the piping connecting multiple containers, or in a single container with an outlet and inlet connected by piping for circulation filtration. The filters used for filtration can be connected in a straight line or in parallel.

[0457] [Pattern Formation Method]

[0458] 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.

[0459] 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.

[0460] 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 2The 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.

[0461] 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.

[0462] After exposure or PEB, the resist film, which has been exposed for 3 seconds to 3 minutes (preferably 5 seconds to 2 minutes) using common methods such as dip, immersion, or spray, is developed using a developer solution containing 0.1% to 10% by mass, preferably 2% to 5% by mass, of alkaline aqueous solutions such as tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), tetrapropylammonium hydroxide (TPAH), or tetrabutylammonium hydroxide (TBAH). This will form the desired pattern. When using a positive resist material, the exposed areas will dissolve in the developer solution, while the unexposed areas will not dissolve, 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 developer solution, while the unexposed areas dissolve.

[0463] 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.

[0464] 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.

[0465] 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.

[0466] 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.

[0467] 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.

[0468] The solvents of the aforementioned aromatic family include: toluene, xylene, ethylbenzene, cumene, tert-butylbenzene, mesitylene, etc.

[0469] 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.

[0470] 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.

[0471] [Example]

[0472] 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.

[0473] The structures of the acid-generating sulfonate salts PAG-1 to PAG-34 used in the resist materials are shown below. PAG-1 to PAG-34 are synthesized by ion exchange of ammonium salts of fluorinated sulfonic acid that provide the following anions with sulfonate chloride that provides the following cations.

[0474] [Chemistry 133]

[0475]

[0476] [Chemistry 134]

[0477]

[0478] [Chemistry 135]

[0479]

[0480] [Chemistry 136]

[0481]

[0482] [Chemistry 137]

[0483]

[0484] [Chemistry 138]

[0485]

[0486] [Chemistry 139]

[0487]

[0488] [Chemistry 140]

[0489]

[0490] [Synthetic Example] Synthesis of basic polymers (polymers P-1 to P-5)

[0491] The monomers were combined and copolymerized in THF as a solvent. The reaction solution was then added to methanol, and the precipitated solid was washed with hexane, separated, and dried to obtain the base polymers (polymers P-1 to P-5) with the compositions shown below. The composition of the obtained base polymers was utilized... 1 The results were confirmed by H-NMR, and Mw and Mw / Mn were confirmed using GPC (solvent: THF, standard: polystyrene).

[0492] [Chemistry 141]

[0493]

[0494] [Examples 1-40, Comparative Examples 1-4] Preparation and Evaluation of Corrosion Resist Materials

[0495] (1) Preparation of corrosion-resistant materials

[0496] A solution prepared by dissolving each component in a solvent containing 100 ppm of Polyfox PF-636 (manufactured by OMNOVA Corporation) as a surfactant, according to the compositions shown in Tables 1-3, was filtered through a 0.2 μm filter to obtain a corrosion resist material.

[0497] The components in Tables 1-3 are as follows.

[0498] Organic solvents: PGMEA (propylene glycol monomethyl ether acetate), EL (ethyl lactate)

[0499] DAA (diacetone alcohol)

[0500] • Acid-generating agents: bPAG-1, bPAG-2

[0501] [Chemistry 142]

[0502]

[0503] • Comparison of acid-generating agents: cPAG-1 to cPAG-4

[0504] [Chemistry 143]

[0505]

[0506] Quenching agents: Q-1, Q-2

[0507] [Chemistry 144]

[0508]

[0509] (2) Evaluation of EUV lithography

[0510] The photoresist materials shown in Tables 1-3 were spin-coated onto a Si substrate with a silicon-containing spin-coated hard mask SHB-A940 (43% by mass) manufactured by Shin-Etsu Chemical Co., Ltd., with a film thickness of 20 nm. The film was pre-baked at 105°C for 60 seconds using a hot plate to obtain a photoresist film with a thickness of 50 nm. The aforementioned photoresist film was exposed using an ASML EUV scanning exposure machine NXE3400 (NA 0.33, σ 0.9 / 0.6, quadrupole illumination, mask with a hole pattern of 40 nm pitch and +20% deviation on the wafer). PEB was performed on the hot plate at the temperatures listed in Tables 1-3 for 60 seconds, followed by development with a 2.38% by mass TMAH aqueous solution for 30 seconds to form a hole pattern with a size of 20 nm.

[0511] 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.

[0512] [Table 1]

[0513]

[0514]

[0515] [Table 2]

[0516]

[0517]

[0518] [Table 3]

[0519]

[0520] As shown in Tables 1-3, the corrosion resist material of the present invention containing the sulfite salt represented by formula (1) as an acid generating agent has good CDU.

Claims

1. A corrosion resist material comprising: an acid generating agent containing a sulfite salt represented by formula (1); In the formula, p is 0, q is an integer from 0 to 4, r is 1, and s is 1; R 1 It can be a single bond, ether bond, thioether bond, or ester bond; R 2 It is a single bond or an alkyl diene with 1 to 20 carbon atoms, and the alkyl diene may optionally 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 optionally contain an oxygen atom or a sulfur atom; furthermore, R 3 and R 4 They can be arbitrarily bonded to each other and together with the carbon atoms they are bonded to form a ring; 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, wherein the saturated hydrocarbon group and the aryl group may optionally 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 is a hydroxyl, carboxyl, nitro, cyano, fluorine atom, chlorine atom, bromine atom, iodine atom or amino, or optionally contains at least one of fluorine atom, chlorine atom, bromine atom, iodine atom, hydroxyl, amino and ether bond, a saturated hydrocarbon group with 1 to 20 carbon atoms, a saturated hydrocarbon oxy group with 1 to 20 carbon atoms, a saturated hydrocarbon carbonyl oxy group with 2 to 20 carbon atoms, a saturated hydrocarbon oxy carbonyl group with 2 to 20 carbon atoms, or a saturated hydrocarbon sulfonyl oxy group with 1 to 4 carbon atoms; R 7 The hydrocarbon group containing 1 to 20 carbon atoms is selected; 2 R 7 They can be identical or dissimilar, and can be optionally bonded to each other and together with the sulfur atoms they are bonded to form a ring; X - It is a non-nucleophilic relative ion.

2. The corrosion resist material according to claim 1, wherein, The non-nucleophilic relative ion is a sulfonic acid anion, an imide anion, or a methylation anion.

3. The resist material according to claim 1 or 2 further contains an organic solvent.

4. The resist material according to claim 1 or 2 further contains a base polymer.

5. The corrosion resist material according to claim 4, wherein, The basic polymer is one that contains repeating units represented by formula (a1) or formula (a2); In the formula, R A Each can be independently a hydrogen atom or a methyl group; X 1 It is a single bond, a phenylene or naphthylene group, or a linking group containing at least one of the following: an ester bond, an ether bond, and a lactone ring, having 1 to 12 carbon atoms; X 2 It is a single bond or an ester bond; X 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 a portion of the -CH2- group of the alkyl diene is optionally substituted 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.

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

7. The corrosion resist material according to claim 4, wherein, The basic polymer contains at least one repeating unit selected from the following formulas (f1) to (f3); In the formula, R A Each can be independently a hydrogen atom or a methyl group; Z 1 It is a single bond, an aliphatic hydrocarbon group with 1 to 6 carbon atoms, a phenylene group, a naphthylene group, or a group with 7 to 18 carbon atoms obtained by combining them, or -OZ. 11 -、-C(=O)-OZ 11 -or-C(=O)-NH-Z 11 -;Z 11 It is an aliphatic alkylene group, phenylene group, naphthylene group or a combination thereof with 7 to 18 carbon atoms, having 1 to 6 carbon atoms, and optionally containing a carbonyl group, ester bond, ether bond or hydroxyl group; Z 2 It is a single bond or an ester bond; Z 3 For single key, -Z 31 -C(=O)-O-、-Z 31 -O- or -Z 31 -OC(=O)-;Z 31 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 optionally contains a carbonyl group, an ester bond, an ether bond, an iodine atom, or a bromine atom; Z 4 It is methylene, 2,2,2-trifluoro-1,1-ethanediyl or carbonyl; Z 5 Single bond, methylene, ethylene, phenylene, fluorinated phenylene, phenylene substituted with trifluoromethyl, -OZ 51 -、-C(=O)-OZ 51 -or-C(=O)-NH-Z 51 -;Z 51 It is an aliphatic alkylene group, phenylene, fluorinated phenylene, or phenylene substituted with trifluoromethyl, having 1 to 6 carbon atoms, and optionally contains a carbonyl group, ester bond, ether bond, hydroxyl group, or halogen atom; R 21 ~R 28 Each is independently a halogen atom, or an optional hydrocarbon group containing heteroatoms with 1 to 20 carbon atoms; also, R 23 and R 24 Or R 26 and R 27 They can be arbitrarily bonded to each other and together with the sulfur atoms they are bonded to form a ring; M - It is a non-nucleophilic relative ion.

8. The resist material according to claim 1 or 2 further contains a surfactant.

9. 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 8. The resist film was exposed to high-energy rays, and The exposed resist film was developed using a developer.

10. The pattern forming method according to claim 9, wherein, The high-energy rays are KrF excimer lasers, ArF excimer lasers, electron beams, or extreme ultraviolet rays with wavelengths of 3-15 nm.

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