Resist material and pattern forming method

Abstract

The invention relates to a resist material and a pattern forming method. The present invention addresses the problem of providing: a resist material having high sensitivity regardless of the positive type or the negative type and improved LWR and CDU; and a pattern forming method using the same. The solution of this problem is a resist material containing a sulfonium salt of an iodinated phenol compound.

Description

Technical Field

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

[0002] With the high integration and high speed of LSIs, the miniaturization of pattern rules has been rapidly progressing. This is because of the spread of 5G high-speed communication and artificial intelligence (AI), and high-performance devices for processing them have become necessary. Regarding the most advanced miniaturization technology, mass production of devices at the 5nm node by extreme ultraviolet (EUV) lithography with a wavelength of 13.5nm is already underway. In addition, discussions on the use of EUV lithography for next-generation 3nm node and next-next-generation 2nm node devices have been carried out, and IMEC in Belgium has announced the development of devices.

[0003] As miniaturization progresses, image blurring due to acid diffusion has also become a problem. In order to ensure the resolution of fine patterns with a size of 45nm or less, it has been proposed that not only the improvement of the dissolution contrast as previously claimed, but also the control of acid diffusion is important (Non-Patent Document 1). However, since chemically amplified resist materials use acid diffusion to improve sensitivity and contrast, if the post-exposure bake (PEB) temperature is lowered or the time is shortened to suppress acid diffusion to the limit, the sensitivity and contrast will be significantly reduced.

[0004] A trade-off relationship among sensitivity, resolution, and line width roughness (LWR) is exhibited. In order to improve the resolution, it is necessary to suppress acid diffusion, but if the acid diffusion distance becomes short, the sensitivity will decrease.

[0005] It is effective to add an acid generator that generates a bulky acid to suppress acid diffusion. Thus, it has been proposed to contain a repeating unit derived from an onium salt having a polymerizable unsaturated bond in a polymer. At this time, the polymer also functions as an acid generator (polymer-bonded acid generator). Patent Document 1 proposes sulfonium salts and iodonium salts having a polymerizable unsaturated bond that generate specific sulfonic acids. Patent Document 2 proposes sulfonium salts in which sulfonic acid is directly bonded to the main chain.

[0006] The acid-labile group used in the (meth)acrylate polymer for ArF resist materials undergoes a deprotection reaction by using a photoacid generator that generates a sulfonic acid with a fluorine atom substituted at the α-position. However, when using a photoacid generator that generates a sulfonic acid or carboxylic acid without a fluorine atom substituted at the α-position, the deprotection reaction does not occur. If a sulfonium salt or iodonium salt that generates a sulfonic acid with a fluorine atom substituted at the α-position is mixed with a sulfonium salt or iodonium salt that generates a sulfonic acid without a fluorine atom substituted at the α-position, the sulfonium salt or iodonium salt that generates a sulfonic acid without a fluorine atom substituted at the α-position will cause ion exchange with the sulfonic acid with a fluorine atom substituted at the α-position. The sulfonic acid with a fluorine atom substituted at the α-position generated by light irradiation will revert to a sulfonium salt or iodonium salt due to ion exchange. Therefore, the sulfonium salt or iodonium salt of a sulfonic acid or carboxylic acid without a fluorine atom substituted at the α-position will function as a quencher. There has been proposed a resist material that uses a sulfonium salt of a carboxylic acid-generating compound as a quencher (Patent Document 3).

[0007] There has been proposed a resist material that uses a sulfonium salt of a phenol compound with a fluorinated benzene ring as a quencher (Patent Documents 4 and 5). The sulfonium salt of the phenol compound generates phenol after decomposition. Since the phenol compound has little swelling in an alkaline developer, it has the effect of preventing pattern collapse caused by swelling. However, the effect of fluorine in suppressing acid diffusion is low, so acid diffusion will increase accordingly, and LWR and size uniformity (CDU) will deteriorate. In addition, in the sulfonium salt of the fluorinated phenol compound, since the acidity of the fluorinated phenol is low, it is prone to thermal decomposition when made into a sulfonium salt, and the resist material added with it has a problem of high sensitivity during storage.

[0008] Prior Art Documents

[0009] Patent Documents

[0010] [Patent Document 1] Japanese Unexamined Patent Application Publication No. 2006-045311

[0011] [Patent Document 2] Japanese Unexamined Patent Application Publication No. 2006-178317

[0012] [Patent Document 3] Japanese Unexamined Patent Application Publication No. 2007-114431

[0013] [Patent Document 4] Japanese Unexamined Patent Application Publication No. 2016-6495

[0014] [Patent Document 5] Japanese Unexamined Patent Application Publication No. 2019-191578

[0015] Non-Patent Documents

[0016] [Non-Patent Document 1] SPIE Vol.6520 65203L-1(2007) Summary of the Invention

[0017] [Problems to be Solved by the Invention]

[0018] In a resist material, it is desired to develop a quencher that can improve the LWR of line patterns, the CDU of hole patterns, and also improve the sensitivity. Therefore, it is necessary to further reduce the blurring of the image caused by diffusion.

[0019] The present invention has been made in view of the above circumstances, and an object thereof is to provide a resist material that has high sensitivity for both positive and negative types, and has improved LWR and CDU, and a pattern forming method using the same.

[0020] [Means for Solving the Problem]

[0021] As a result of repeated and in-depth studies by the present inventors to achieve the above object, it has been found that the sulfonium salt of an iodinated phenol compound is a quencher that inhibits acid diffusion, and by virtue of its excellent acid diffusion inhibition effect, prevention of pattern collapse due to reduced swelling, and improvement of contrast due to strong absorption of iodine atoms, a resist material with improved LWR and CDU, excellent resolution, and a wide process latitude can be obtained. In addition, since the acidity of iodinated phenol is high, its sulfonium salt is not easily thermally decomposed, and the storage stability of the resist material added with it is excellent, and thus the present invention has been completed.

[0022] That is, the present invention provides the following resist material and pattern forming method.

[0023] 1. A resist material containing: a sulfonium salt of an iodinated phenol compound.

[0024] 2. The resist material according to 1., wherein the sulfonium salt is represented by the following formula (1).

[0025] [Chemical Formula 1]

[0026]

[0027] In the formula, m is 1, 2, 3, 4 or 5. n is 0, 1, 2, 3 or 4. However, 1 ≤ m + n ≤ 5.

[0028] R 1 Each independently represents a halogen atom other than an iodine atom, a hydroxyl group, a nitro group, a cyano group, a hydrocarbon group having 1 to 20 carbon atoms, a hydrocarbon oxy group having 1 to 20 carbon atoms, a hydrocarbon carbonyloxy group having 2 to 20 carbon atoms, or a hydrocarbon sulfonyloxy group having 1 to 20 carbon atoms, and the hydrocarbon group, hydrocarbon oxy group, hydrocarbon carbonyloxy group, and hydrocarbon sulfonyloxy group may also have at least 1 selected from a halogen atom, an oxygen atom, a sulfur atom, and a nitrogen atom.

[0029] R 2 ~R 4 Each independently represents a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms that may contain a hetero atom. Also, R 2 and R 3They can also be bonded to each other and together with the sulfur atoms to which they are bonded to form a ring.

[0030] 3. The resist material according to 1. or 2. further contains a base polymer.

[0031] 4. The resist material according to 3., wherein the base polymer contains at least one selected from the repeating unit represented by the following formula (a1) and the repeating unit represented by the following formula (a2).

[0032] [Chemical formula 2]

[0033]

[0034] In the formula, R A are each independently a hydrogen atom or a methyl group.

[0035] X 1 is a single bond, a phenylene group, a naphthylene group, or a linking group having 1 to 12 carbon atoms containing at least one selected from an ester bond, an ether bond, and a lactone ring, and the phenylene group, naphthylene group, and linking group may also have at least one selected from a halogen atom, a hydroxyl group, a saturated hydrocarbon group oxy group having 1 to 8 carbon atoms, and a saturated hydrocarbon group carbonyl oxy group having 2 to 8 carbon atoms.

[0036] X 2 is a single bond, an ester bond, or an amide bond.

[0037] X 3 is a single bond, an ether bond, or an ester bond.

[0038] R 11 and R 12 are each independently an acid-labile group.

[0039] R 13 is a hydroxyl group, a halogen atom, a trifluoromethyl group, a cyano group, or a saturated hydrocarbon group having 1 to 6 carbon atoms.

[0040] R 14 is a single bond or an alkanediyl group having 1 to 6 carbon atoms, and a part of -CH 2 - of the alkanediyl group may also be substituted with an ether bond or an ester bond.

[0041] a is 1 or 2. b is an integer from 0 to 4. However, 1 ≤ a + b ≤ 5.

[0042] 5. The resist material according to 4., which is a chemically amplified positive resist material.

[0043] 6. The resist material according to 3., wherein the base polymer does not contain an acid-labile group.

[0044] 7. The resist material according to 6., which is a chemically amplified negative resist material.

[0045] 8. The resist material according to any one of 3. to 7., wherein the base polymer contains at least one selected from the repeating unit represented by the following formula (f1), the repeating unit represented by the following formula (f2), the repeating unit represented by the following formula (f3), the repeating unit represented by the following formula (f4), and the repeating unit represented by the following formula (f5).

[0046] [Chemical formula 3]

[0047]

[0048] In the formula, R A are each independently a hydrogen atom or a methyl group.

[0049] Z 1 is a single bond, an aliphatic alkylene group having 1 to 6 carbon atoms, a phenylene group, a naphthylene group, a group having 7 to 18 carbon atoms obtained by combining them, or -O-Z 11 -, -C(=O)-O-Z 11 -, or -C(=O)-NH-Z 11 -. Z 11 is an aliphatic alkylene 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, and may also contain a carbonyl group, an ester bond, an ether bond, or a hydroxyl group.

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

[0051] Z 3 is a single bond, -Z 31 -C(=O)-O-, -Z 31 -O-, or -Z 31 -O-C(=O)-. Z 31 is an aliphatic alkylene group having 1 to 12 carbon atoms, a phenylene group, or a group having 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.

[0052] Z 4 is a methylene group, 2,2,2-trifluoro-1,1-ethanediyl, or a carbonyl group.

[0053] Z 5 is a single bond, a methylene group, an ethylene group, a phenylene group, a fluorinated phenylene group, a phenylene group substituted with a trifluoromethyl group, -O-Z 51 -, -C(=O)-O-Z 51 -, or -C(=O)-NH-Z 51 -. Z 51 is an aliphatic alkylene group having 1 to 6 carbon atoms, a phenylene group, a fluorinated phenylene group, or a phenylene group substituted with a trifluoromethyl group, and may also contain a carbonyl group, an ester bond, an ether bond, a halogen atom, or a hydroxyl group.

[0054] Z6 is a single bond, a phenylene group, a naphthylene ring, an ester bond or an amide bond.

[0055] Z 7A is a single bond or a divalent organic group having 1 to 24 carbon atoms, and may also have at least one selected from a halogen atom, an oxygen atom, a nitrogen atom and a sulfur atom.

[0056] Z 7B is a monovalent organic group having 1 to 10 carbon atoms, and may also have at least one selected from a halogen atom, an oxygen atom, a nitrogen atom and a sulfur atom.

[0057] Z 8 is a single bond, an ether bond, an ester bond, a thioether bond or an alkanediyl group having 1 to 6 carbon atoms.

[0058] Z 9 is a trivalent organic group having 1 to 12 carbon atoms, and may also have at least one selected from an oxygen atom, a nitrogen atom and a sulfur atom.

[0059] R 21 ~R 25 are each independently a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom. Further, R 23 and R 24 may also be bonded to each other and form a ring together with the sulfur atom to which they are bonded.

[0060] R 26 are each independently a saturated hydrocarbon group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a fluorine atom, an iodine atom, a trifluoromethoxy group, a difluoromethoxy group, a cyano group or a nitro group.

[0061] Circular R is an (j + 2)-valent aromatic hydrocarbon group having 6 to 10 carbon atoms.

[0062] j are each independently an integer from 0 to 5.

[0063] M - is a non-nucleophilic counter ion.

[0064] 9. The resist material according to any one of 1. to 8., further comprising an acid generator that generates a strong acid.

[0065] 10. The resist material according to 9., wherein the acid generator generates a sulfonic acid, an imide acid or a methylated acid.

[0066] 11. The resist material according to any one of 1. to 10., further comprising an organic solvent.

[0067] 12. The resist material according to any one of 1. to 11., further comprising a surfactant.

[0068] 13. A pattern forming method, comprising the following steps:

[0069] A resist film is formed on a substrate using a resist material according to any one of 1. to 12.,

[0070] the aforementioned resist film is exposed to high-energy rays, and

[0071] the aforementioned exposed resist film is developed using a developer.

[0072] 14. The pattern forming method according to 13., wherein the aforementioned high-energy rays are KrF excimer laser, ArF excimer laser, electron beam (EB), or EUV with a wavelength of 3 to 15 nm.

[0073] [Effects of the Invention]

[0074] The sulfonium salt of the aforementioned iodinated phenol compound is a quencher that inhibits acid diffusion. Thereby, a resist material with characteristics of low acid diffusion, small LWR, and improved CDU can be constructed. Detailed Description of the Invention

[0075] [Resist Material]

[0076] The resist material of the present invention contains a quencher containing a sulfonium salt of an iodinated phenol compound.

[0077] [Quencher]

[0078] The sulfonium salt of the aforementioned iodinated phenol compound is preferably represented by the following formula (1).

[0079] [Chemical Formula 4]

[0080]

[0081] In formula (1), m is 1, 2, 3, 4, or 5. n is 0, 1, 2, 3, or 4. However, 1 ≤ m + n ≤ 5.

[0082] In formula (1), R 1 are each independently a halogen atom other than an iodine atom, a hydroxyl group, a nitro group, a cyano group, a hydrocarbon group having 1 to 20 carbon atoms, a hydrocarbon oxy group having 1 to 20 carbon atoms, a hydrocarbon carbonyloxy group having 2 to 20 carbon atoms, or a hydrocarbon sulfonyloxy group having 1 to 20 carbon atoms.

[0083] R 1 The hydrocarbon group represented, as well as the hydrocarbon moieties of the hydrocarbon oxy group, hydrocarbon carbonyloxy group, and hydrocarbon sulfonyloxy group, may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof can be listed and the examples described later can be used as R 2 ~R 4Examples of the same are hydrocarbon groups having 1 to 20 carbon atoms. Further, the aforementioned hydrocarbon group, hydrocarbon oxy group, hydrocarbon carbonyl oxy group, and hydrocarbon sulfonyl oxy group may also have at least one selected from a halogen atom, an oxygen atom, a sulfur atom, and a nitrogen atom. That is, part or all of the hydrogen atoms of these groups may also be substituted with a group containing at least one selected from a halogen atom, an oxygen atom, a sulfur atom, and a nitrogen atom, and a part of -CH 2 - of these groups may also be substituted with a group containing at least one selected from an oxygen atom, a sulfur atom, and a nitrogen atom, and as a result, it may contain a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a nitro group, a carbonyl group, an ether bond, an ester bond, a sulfonate bond, a carbonate bond, a lactone ring, a sultone ring, a carboxylic anhydride (-C(=O)-O-C(=O)-), a haloalkyl group, etc.

[0084] Specific examples of the anion of the sulfonium salt represented by formula (1) are as shown below, but are not limited thereto.

[0085] [Chemical formula 5]

[0086]

[0087] [Chemical formula 6]

[0088]

[0089] [Chemical formula 7]

[0090]

[0091] [Chemical formula 8]

[0092]

[0093] [Chemical formula 9]

[0094]

[0095] [Chemical formula 10]

[0096]

[0097] [Chemical formula 11]

[0098]

[0099] [Chemical formula 12]

[0100]

[0101] [Chemical formula 13]

[0102]

[0103] [Chemical formula 14]

[0104]

[0105] [Chemistry 15]

[0106]

[0107] [Chemistry 16]

[0108]

[0109] In formula (1), R 2 ~R 4 Each independently represents a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms which may contain a heteroatom.

[0110] R 2 ~R 4 Specific examples of the halogen atom represented by include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like.

[0111] R 2 ~R 4 The hydrocarbon group having 1 to 20 carbon atoms represented by may be saturated or unsaturated, and may be straight-chain, branched, or cyclic. Specific examples thereof include: alkyl groups having 1 to 20 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, n-hexyl, n-octyl, n-nonyl, n-decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, heptadecyl, octadecyl, nonadecyl, eicosyl, etc.; cyclic saturated hydrocarbon groups having 3 to 20 carbon atoms, such as cyclopropyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norbornyl, and adamantyl, etc.; ethenyl, propenyl, butenyl, hexenyl Alkenyl groups with 2 to 20 carbon atoms, such as ethynyl, propynyl, butynyl, etc.; alkynyl groups with 2 to 20 carbon atoms, such as cyclohexenyl and norbornyl, etc.; aryl groups with 6 to 20 carbon atoms, such as 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.; aralkyl groups with 7 to 20 carbon atoms, such as benzyl and phenethyl, etc.; groups obtained by combining them, etc.

[0112] In addition, part or all of the hydrogen atoms of the aforementioned hydrocarbon group may be substituted by a group containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, halogen atoms, etc., and the -CH 2A part of the "-" may also be substituted by a group containing a heteroatom such as an oxygen atom, a sulfur atom, a nitrogen atom, etc., and as a result, it may also contain a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a nitro group, a mercapto group, a pentafluorothioalkyl group, a carbonyl group, an ether bond, an ester bond, a sulfonate bond, a carbonate bond, a lactone ring, a sultone ring, a carboxylic anhydride (-C(=O)-O-C(=O)-), a haloalkyl group, etc.

[0113] Also, R 2 and R 3 may also be bonded to each other and form a ring together with the sulfur atom to which they are bonded. In this case, the aforementioned ring is preferably one having the following structure.

[0114] [Chemical formula 17]

[0115]

[0116] In the formula, the dashed line is a bond to the atom of R 4 .

[0117] Specific examples of the cation of the sulfonium salt represented by formula (1) may be those shown below, but are not limited thereto.

[0118] [Chemical formula 18]

[0119]

[0120] [Chemical formula 19]

[0121]

[0122] [Chemical formula 20]

[0123]

[0124] [Chemical formula 21]

[0125]

[0126] [Chemical formula 22]

[0127]

[0128] [Chemical formula 23]

[0129]

[0130] [Chemical formula 24]

[0131]

[0132] [Chemical formula 25]

[0133]

[0134] [Chemical formula 26]

[0135]

[0136] [Chemical formula 27]

[0137]

[0138] [Chemical formula 28]

[0139]

[0140] [Chemical formula 29]

[0141]

[0142] [Chemical formula 30]

[0143]

[0144] [Chemical formula 31]

[0145]

[0146] [Chemical formula 32]

[0147]

[0148] [Chemical formula 33]

[0149]

[0150] [Chemical formula 34]

[0151]

[0152] [Chemical formula 35]

[0153]

[0154] [Chemical formula 36]

[0155]

[0156] [Chemical formula 37]

[0157]

[0158] [Chemical formula 38]

[0159]

[0160] [Chemical formula 39]

[0161]

[0162] [Chemical formula 40]

[0163]

[0164] [Chemical Formula 41]

[0165]

[0166] [Chemical Formula 42]

[0167]

[0168] [Chemical Formula 43]

[0169]

[0170] [Chemical Formula 44]

[0171]

[0172] [Chemical Formula 45]

[0173]

[0174] [Chemical Formula 46]

[0175]

[0176] [Chemical Formula 47]

[0177]

[0178] [Chemical Formula 48]

[0179]

[0180] [Chemical Formula 49]

[0181]

[0182] [Chemical Formula 50]

[0183]

[0184] [Chemical Formula 51]

[0185]

[0186] [Chemical Formula 52]

[0187]

[0188] The sulfonium salt represented by formula (1) can be synthesized, for example, by ion-exchanging a hydrochloride or carbonate of a sulfonium cation with an ammonium salt of an iodinated phenol compound.

[0189] In the resist material of the present invention, the content of the sulfonium salt represented by the formula (1) is preferably 0.001 to 50 parts by mass, more preferably 0.01 to 40 parts by mass, relative to 100 parts by mass of the base polymer described later. The sulfonium salt represented by the formula (1) may be used alone or in combination of two or more.

[0190] [Base polymer]

[0191] The base polymer contained in the resist material of the present invention, in the case of a positive resist material, contains a repeating unit having an acid-labile group. The repeating unit having an acid-labile group is preferably a repeating unit represented by the following formula (a1) (hereinafter also referred to as repeating unit a1) or a repeating unit represented by the formula (a2) (hereinafter also referred to as repeating unit a2).

[0192] [Chemical formula 53]

[0193]

[0194] In the formulas (a1) and (a2), R A are each independently a hydrogen atom or a methyl group. X 1 is a single bond, a phenylene group, a naphthylene group, or a linking group having 1 to 12 carbon atoms containing at least one selected from an ester bond, an ether bond, and a lactone ring, and the phenylene group, naphthylene group, and linking group may also have at least one selected from a halogen atom, a hydroxyl group, a saturated hydrocarbon group oxy group having 1 to 8 carbon atoms, and a saturated hydrocarbon group carbonyl oxy group having 2 to 8 carbon atoms. X 2 is a single bond, an ester bond, or an amide bond. X 3 is a single bond, an ether bond, or an ester bond. R 11 and R 12 are each independently an acid-labile group. R 13 is a hydroxyl group, a halogen atom, a trifluoromethyl group, a cyano group, or a saturated hydrocarbon group having 1 to 6 carbon atoms. R 14 is a single bond or an alkanediyl group having 1 to 6 carbon atoms, and a part of -CH 2 - of the alkanediyl group may also be substituted with an ether bond or an ester bond. a is 1 or 2. b is an integer of 0 to 4. However, 1 ≤ a + b ≤ 5.

[0195] Specific examples of the monomer providing the repeating unit a1 are as follows, but are not limited thereto. In addition, in the following formulas, R A and R 11 are the same as described above.

[0196] [Chemical formula 54]

[0197]

[0198] [Chemical formula 55]

[0199]

[0200] Specific examples of the monomer providing the repeating unit a2 are as follows, but are not limited thereto. In addition, in the following formula, R A and R 12 are the same as described above.

[0201] [Chemical formula 56]

[0202]

[0203] R 11 or R 12 represents an acid-labile group, and various selections are available. For example, those represented by the following formulas (AL-1) to (AL-3) can be cited.

[0204] [Chemical formula 57]

[0205]

[0206] In the formula, the dashed line is an atomic bond.

[0207] In formula (AL-1), c is an integer from 0 to 6. R L1 is a tertiary hydrocarbon group having 4 to 20 carbon atoms, preferably 4 to 15 carbon atoms, a trihydrocarbylsilyl group in which each hydrocarbon group is a saturated hydrocarbon group having 1 to 6 carbon atoms, a saturated hydrocarbon group having 4 to 20 carbon atoms containing a carbonyl group, an ether bond or an ester bond, or a group represented by formula (AL-3). In addition, the tertiary hydrocarbon group means a group obtained by detaching a hydrogen atom from a tertiary carbon atom of a hydrocarbon.

[0208] R L1 The tertiary hydrocarbon group represented can be saturated or unsaturated, branched or cyclic. Specific examples thereof include: tert-butyl, tert-pentyl, 1,1-diethylpropyl, 1-ethylcyclopentyl, 1-butylcyclopentyl, 1-ethylcyclohexyl, 1-butylcyclohexyl, 1-ethyl-2-cyclopentenyl, 1-ethyl-2-cyclohexenyl, 2-methyl-2-adamantyl, etc. Specific examples of the above trihydrocarbylsilyl group include: trimethylsilyl, triethylsilyl, dimethyl-tert-butylsilyl, etc. The saturated hydrocarbon group containing a carbonyl group, an ether bond or an ester bond can be any of linear, branched or cyclic, preferably cyclic. Specific examples thereof include: 3-oxocyclohexyl, 4-methyl-2-oxooxacyclohexan-4-yl, 5-methyl-2-oxooxacyclopentan-5-yl, 2-tetrahydropyranyl, 2-tetrahydrofuranyl, etc.

[0209] Specific examples of the acid-labile group represented by formula (AL-1) include: tert-butoxycarbonyl, tert-butoxycarbonylmethyl, tert-amyloxycarbonyl, tert-amyloxycarbonylmethyl, 1,1-diethylpropyloxycarbonyl, 1,1-diethylpropyloxycarbonylmethyl, 1-ethylcyclopentyloxycarbonyl, 1-ethylcyclopentyloxycarbonylmethyl, 1-ethyl-2-cyclopentenyl- oxycarbonyl, 1-ethyl-2-cyclopentenyl-oxycarbonylmethyl, 1-ethoxyethoxycarbonylmethyl, 2-tetrahydropyranyloxycarbonylmethyl, 2-tetrahydrofuranyloxycarbonylmethyl, and the like.

[0210] In addition, the acid-labile group represented by formula (AL-1) may also include the groups represented by the following formulas (AL-1)-1 to (AL-1)-10.

[0211] [Chemical formula 58]

[0212]

[0213] In the formulas, the dashed line represents an atomic bond.

[0214] In formulas (AL-1)-1 to (AL-1)-10, c is the same as described above. R L8 are each independently a saturated hydrocarbon group having 1 to 10 carbon atoms or an aryl group having 6 to 20 carbon atoms. R L9 is a hydrogen atom or a saturated hydrocarbon group having 1 to 10 carbon atoms. R L10 is a saturated hydrocarbon group having 2 to 10 carbon atoms or an aryl group having 6 to 20 carbon atoms. The aforementioned saturated hydrocarbon group may be linear, branched, or cyclic.

[0215] In formula (AL-2), R L2 and R L3 are each independently a hydrogen atom or a saturated hydrocarbon group having 1 to 18 carbon atoms, preferably 1 to 10 carbon atoms. The aforementioned saturated hydrocarbon group may be linear, branched, or cyclic, and specific examples thereof include: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, cyclopentyl, cyclohexyl, 2-ethylhexyl, n-octyl, and the like.

[0216] In formula (AL-2), R L4 is a hydrocarbon group having 1 to 18 carbon atoms, preferably 1 to 10 carbon atoms, which may also contain a heteroatom. The aforementioned hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples of the aforementioned hydrocarbon group include: saturated hydrocarbon groups having 1 to 18 carbon atoms, etc., and a part of the hydrogen atoms thereof may also be substituted with a hydroxyl group, an alkoxy group, an oxo group, an amino group, an alkylamino group, etc. Specific examples of such a substituted saturated hydrocarbon group include those shown below, etc.

[0217] [Chemical formula 59]

[0218]

[0219] In the formula, the dashed line represents an atomic bond.

[0220] R L2 and R L3 、R L2 and R L4 、or R L3 and R L4 may also be bonded to each other and together with the carbon atoms to which they are bonded form a ring or together with carbon atoms and oxygen atoms form a ring. At this time, the R L2 and R L3 、R L2 and R L4 、or R L3 and R L4 independently represent an alkanediyl group having 1 to 18 carbon atoms, preferably 1 to 10 carbon atoms. The carbon number of the ring formed by their bonding is preferably 3 to 10, more preferably 4 to 10.

[0221] Among the acid-labile groups represented by formula (AL-2), specific examples of linear or branched ones may include those represented by the following formulas (AL-2)-1 to (AL-2)-69, but are not limited thereto. In addition, in the following formulas, the dashed line represents an atomic bond.

[0222] [Chemical formula 60]

[0223]

[0224] [Chemical formula 61]

[0225]

[0226] [Chemical formula 62]

[0227]

[0228] [Chemical formula 63]

[0229]

[0230] Among the acid-labile groups represented by formula (AL-2), specific examples of cyclic ones may include tetrahydrofuran-2-yl, 2-methyltetrahydrofuran-2-yl, tetrahydropyran-2-yl, 2-methyltetrahydropyran-2-yl, etc.

[0231] Furthermore, acid-labile groups may include groups represented by the following formula (AL-2a) or (AL-2b). Using the aforementioned acid-labile groups, the base polymer can also be crosslinked intermolecularly or intramolecularly.

[0232] [Chemical formula 64]

[0233]

[0234] In the formula, the dashed line represents an atomic bond.

[0235] In formula (AL-2a) or (AL-2b), R L11 and R L12 are each independently a hydrogen atom or a saturated hydrocarbon group having 1 to 8 carbon atoms. The aforementioned saturated hydrocarbon group may be linear, branched, or cyclic. Also, R L11 and R L12 may also be bonded to each other and together with the carbon atoms to which they are bonded form a ring. In this case, R L11 and R L12 are each independently an alkanediyl group having 1 to 8 carbon atoms. R L13 are each independently a saturated alkylene group having 1 to 10 carbon atoms. The aforementioned saturated alkylene group may be linear, branched, or cyclic. d and e are each independently an integer from 0 to 10, preferably an integer from 0 to 5, and f is an integer from 1 to 7, preferably an integer from 1 to 3.

[0236] In formula (AL-2a) or (AL-2b), L A is a (f + 1)-valent aliphatic saturated hydrocarbon group having 1 to 50 carbon atoms, a (f + 1)-valent alicyclic saturated hydrocarbon group having 3 to 50 carbon atoms, a (f + 1)-valent aromatic hydrocarbon group having 6 to 50 carbon atoms, or a (f + 1)-valent heterocyclic group having 3 to 50 carbon atoms. Also, a part of -CH 2 - of these groups may be substituted with a group containing a heteroatom, and a part of the hydrogen atoms of these groups may be substituted with a hydroxyl group, a carboxyl group, an acyl group, or a fluorine atom. L A is preferably a saturated alkylene group having 1 to 20 carbon atoms, a trivalent saturated hydrocarbon group, a tetravalent saturated hydrocarbon group, etc., a saturated hydrocarbon group, an arylene group having 6 to 30 carbon atoms, etc. The aforementioned saturated hydrocarbon group may be linear, branched, or cyclic. L B is -C(=O)-O-, -NH-C(=O)-O-, or -NH-C(=O)-NH-.

[0237] Specific examples of the crosslinked acetal group represented by formula (AL-2a) or (AL-2b) include groups represented by the following formula (AL-2)-70 to (AL-2)-77.

[0238] [Chemical formula 65]

[0239]

[0240] In the formula, the dashed line represents an atomic bond.

[0241] In formula (AL-3), R L5 is a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and the hydrocarbon group may also contain heteroatoms such as an oxygen atom, a sulfur atom, a nitrogen atom, and a fluorine atom. R L6 and RL7 Each is independently a hydrocarbon group having 1 to 20 carbon atoms, and may also contain heteroatoms such as an oxygen atom, a sulfur atom, a nitrogen atom, and a fluorine atom. The aforementioned hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include: an alkyl group having 1 to 20 carbon atoms, a cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, a cyclic unsaturated hydrocarbon group having 3 to 20 carbon atoms, an aryl group having 6 to 10 carbon atoms, etc. Also, R L5 and R L6 , R L5 and R L7 , or R L6 and R L7 may also be bonded to each other and together with the carbon atoms to which they are bonded form an alicyclic ring having 3 to 20 carbon atoms.

[0242] Specific examples of the group represented by formula (AL-3) include: tert-butyl, 1,1-diethylpropyl, 1-ethylnorbornanyl, 1-methylcyclopentyl, 1-ethylcyclopentyl, 1-isopropylcyclopentyl, 1-methylcyclohexyl, 2-(2-methyl)adamantyl, 2-(2-ethyl)adamantyl, tert-pentyl, etc.

[0243] Also, the group represented by formula (AL-3) may also include the groups represented by the following formulas (AL-3)-1 to (AL-3)-22.

[0244] [Chemical formula 66]

[0245]

[0246] In the formula, the dashed line is an atomic bond.

[0247] In formulas (AL-3)-1 to (AL-3)-22, R L14 are each independently a hydrogen atom, an aliphatic hydrocarbon group having 1 to 8 carbon atoms, or an aryl group having 6 to 20 carbon atoms. R L15 and R L17 are each independently a hydrogen atom or a saturated hydrocarbon group having 1 to 20 carbon atoms. R L16 is an aryl group having 6 to 20 carbon atoms. The aforementioned saturated hydrocarbon group may be linear, branched, or cyclic. Also, the aforementioned aryl group is preferably a phenyl group, etc. R L18 is a fluorine atom, an iodine atom, a nitro group, or a trifluoromethyl group. R L19 are each independently a hydrogen atom, a fluorine atom, an iodine atom, a nitro group, a saturated hydrocarbon group having 1 to 8 carbon atoms, or a hydrocarbon oxy group having 1 to 8 carbon atoms. g is an integer from 1 to 5.

[0248] In addition, acid-labile groups may include the groups represented by the following formula (AL-3)-23 or (AL-3)-24. Using the aforementioned acid-labile groups, the polymer can also be crosslinked intramolecularly or intermolecularly.

[0249] [Chemical Formula 67]

[0250]

[0251] In the formula, the dashed line represents an atomic bond.

[0252] In Formulas (AL-3)-23 and (AL-3)-24, R L14 is the same as described above. R L20 is a (h + 1)-valent saturated or unsaturated alkylene group having 1 to 20 carbon atoms or a (h + 1)-valent arylene group having 6 to 20 carbon atoms, and may also contain heteroatoms such as an oxygen atom, a sulfur atom, and a nitrogen atom. The saturated or unsaturated alkylene group may be linear, branched, or cyclic. h is an integer from 1 to 3.

[0253] In addition to these acid-labile groups, acid-labile groups containing an aromatic group described in Japanese Patent Publication No. 5565293, Japanese Patent Publication No. 5434983, Japanese Patent Publication No. 5407941, Japanese Patent Publication No. 5655756, and Japanese Patent Publication No. 5655755 can also be used.

[0254] The aforementioned base polymer may also contain a repeating unit b containing a phenolic hydroxyl group as an adhesion group. Specific examples of the monomer providing the repeating unit b are as shown below, but are not limited thereto. In addition, in the following formula, R A is the same as described above.

[0255] [Chemical Formula 68]

[0256]

[0257] The aforementioned base polymer may also contain a repeating unit c containing a hydroxyl group other than a phenolic hydroxyl group, a lactone ring, a sultone ring, an ether bond, an ester bond, a sulfonate bond, a carbonyl group, a sulfonyl group, a cyano group, or a carboxyl group as another adhesion group. Specific examples of the monomer providing the repeating unit c are as shown below, but are not limited thereto. In addition, in the following formula, R A is the same as described above.

[0258] [Chemical Formula 69]

[0259]

[0260] [Chemical Formula 70]

[0261]

[0262] [Chemical Formula 71]

[0263]

[0264] [Chemical Formula 72]

[0265]

[0266] [Chemical Formula 73]

[0267]

[0268] [Chemical Formula 74]

[0269]

[0270] [Chemical Formula 75]

[0271]

[0272] [Chemical Formula 76]

[0273]

[0274] The aforementioned base polymer may also contain repeating unit d derived from indene, benzofuran, benzothiophene, acenaphthene, chromone, coumarin, norbornadiene or their derivatives. Specific examples of the monomer providing repeating unit d are as shown below, but are not limited thereto.

[0275] [Chemical Formula 77]

[0276]

[0277] The aforementioned base polymer may also contain repeating unit e derived from styrene, vinylnaphthalene, vinylanthracene, vinylpyrene, methylene indane, vinylpyridine or vinylcarbazole.

[0278] The aforementioned base polymer may also contain repeating unit f derived from an onium salt having a polymerizable unsaturated bond. Specific examples of the desirable repeating unit f include: the repeating unit represented by the following formula (f1) (hereinafter also referred to as repeating unit f1), the repeating unit represented by the following formula (f2) (hereinafter also referred to as repeating unit f2), the repeating unit represented by the following formula (f3) (hereinafter also referred to as repeating unit f3), the repeating unit represented by the following formula (f4) (hereinafter also referred to as repeating unit f4), and the repeating unit represented by the following formula (f5) (hereinafter also referred to as repeating unit f5). In addition, repeating units f1 to f5 may be used alone or in combination of two or more.

[0279] [Chemical Formula 78]

[0280]

[0281] In formulas (f1) to (f5), R A are each independently a hydrogen atom or a methyl group.

[0282] In formulas (f1) to (f3), Z 1is a single bond, an aliphatic alkylene group having 1 to 6 carbon atoms, a phenylene group, a naphthylene group, a group having 7 to 18 carbon atoms obtained by combining them, or -O-Z 11 -, -C(=O)-O-Z 11 -, or -C(=O)-NH-Z 11 -. Z 11 is an aliphatic alkylene 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, and may also contain a carbonyl group, an ester bond, an ether bond, or a hydroxyl group. Z 2 is a single bond or an ester bond. Z 3 is a single bond, -Z 31 -C(=O)-O-, -Z 31 -O-, or -Z 31 -O-C(=O)-. Z 31 is an aliphatic alkylene group having 1 to 12 carbon atoms, a phenylene group, or a group having 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. Z 4 is a methylene group, 2,2,2-trifluoro-1,1-ethanediyl, or a carbonyl group. Z 5 is a single bond, a methylene group, an ethylene group, a phenylene group, a fluorophenylene group, a phenylene group substituted with a trifluoromethyl group, -O-Z 51 -, -C(=O)-O-Z 51 -, or -C(=O)-NH-Z 51 -. Z 51 is an aliphatic alkylene group having 1 to 6 carbon atoms, a phenylene group, a fluorophenylene group, or a phenylene group substituted with a trifluoromethyl group, and may also contain a carbonyl group, an ester bond, an ether bond, a halogen atom, or a hydroxyl group. Additionally, Z 1 , Z 11 , Z 31 , and Z 51 The aliphatic alkylene group represented may be saturated or unsaturated, and may be linear, branched, or cyclic.

[0283] In formulas (f4) and (f5), Z 6 is a single bond, a phenylene group, a naphthylene ring, an ester bond, or an amide bond.

[0284] In formula (f4), Z 7A is a single bond or a divalent organic group having 1 to 24 carbon atoms, and may also have at least 1 kind selected from a halogen atom, an oxygen atom, a nitrogen atom, and a sulfur atom.

[0285] Z 7AThe divalent organic group represented can be saturated or unsaturated, and can be linear, branched, or cyclic. Specific examples thereof include C1-C24 alkylene groups in which part or all of the hydrogen atoms are substituted with iodine atoms or bromine atoms. Specific examples of the C1-C24 alkylene groups include: alkanediyl groups such as methanediyl, ethane-1,1-diyl, ethane-1,2-diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, decane-1,10-diyl, undecane-1,11-diyl, dodecane-1,12-diyl, tridecane-1,13-diyl, tetradecane-1,14-diyl, pentadecane-1,15-diyl, hexadecane-1,16-diyl, heptadecane-1,17-diyl, octadecane-1,18-diyl, nonadecane-1,19-diyl, icosane-1,20-diyl; cyclic saturated alkylene groups such as cyclopentanediyl, methylcyclopentanediyl, dimethylcyclopentanediyl, trimethylcyclopentanediyl, tetramethylcyclopentanediyl, cyclohexanediyl, methylcyclohexanediyl, dimethylcyclohexanediyl, trimethylcyclohexanediyl, tetramethylcyclohexanediyl, norbornanediyl, adamantanediyl; arylene groups such as phenylene, methylphenylene, ethylphenylene, n-propylphenylene, isopropylphenylene, n-butylphenylene, isobutylphenylene, sec-butylphenylene, tert-butylphenylene, naphthylene, methylnaphthylene, ethylnaphthylene, n-propylnaphthylene, isopropylnaphthylene, n-butylnaphthylene, isobutylnaphthylene, sec-butylnaphthylene, tert-butylnaphthylene, biphenyldiyl, methylbiphenyldiyl, dimethylbiphenyldiyl; groups obtained by combining them, etc. Also, Z 7A part or all of the hydrogen atoms of can also be substituted with a group containing at least one selected from an oxygen atom, a nitrogen atom, and a sulfur atom, and Z 7A part of the -CH 2 - can also be substituted with a group containing at least one selected from an oxygen atom, a nitrogen atom, and a sulfur atom, and as a result, it may contain a hydroxyl group, an ester bond, an ether bond, an amide bond, a urethane bond, a urea bond, etc.

[0286] In formula (f5), Z 7B is a monovalent organic group having 1 to 10 carbon atoms, and may also have at least one selected from a halogen atom, an oxygen atom, a nitrogen atom, and a sulfur atom.

[0287] Z 7BThe monovalent organic group represented can be saturated or unsaturated, and can be any of linear, branched, or cyclic. Specific examples thereof include hydrocarbon groups having 1 to 10 carbon atoms in which part or all of the hydrogen atoms are substituted with iodine atoms or bromine atoms. Specific examples of the hydrocarbon groups having 1 to 10 carbon atoms include: alkyl groups having 1 to 10 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, 3-pentyl, tert-pentyl, neopentyl, n-hexyl, n-octyl, n-nonyl, n-decyl; cyclic saturated hydrocarbon groups having 3 to 10 carbon atoms such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, adamantyl, norbornyl, cyclopropylmethyl, cyclopropylethyl, cyclobutylmethyl, cyclobutylethyl, cyclopentylmethyl, cyclopentylethyl, cyclohexylmethyl, cyclohexylethyl, methylcyclopropyl, methylcyclobutyl, methylcyclopentyl, methylcyclohexyl, ethylcyclopropyl, ethylcyclobutyl, ethylcyclopentyl, ethylcyclohexyl; alkenyl groups having 2 to 10 carbon atoms such as vinyl, 1-propenyl, 2-propenyl, butenyl, pentenyl, hexenyl, heptenyl, nonenyl, decenyl; alkynyl groups having 2 to 10 carbon atoms such as ethynyl, propynyl, butynyl, pentynyl, hexynyl, heptynyl, octynyl, nonynyl, decynyl; cyclic unsaturated aliphatic hydrocarbon groups having 3 to 10 carbon atoms such as cyclopentenyl, cyclohexenyl, methylcyclopentenyl, methylcyclohexenyl, ethylcyclopentenyl, ethylcyclohexenyl, norbornenyl; aryl groups having 6 to 10 carbon atoms such as phenyl, tolyl, ethylphenyl, n-propylphenyl, isopropylphenyl, n-butylphenyl, isobutylphenyl, sec-butylphenyl, tert-butylphenyl, naphthyl; aralkyl groups having 7 to 10 carbon atoms such as benzyl, phenethyl, phenylpropyl, phenylbutyl; groups obtained by combining them, etc. Also, Z 7B Part or all of the hydrogen atoms of 7B may also be substituted with a group containing at least one selected from an oxygen atom, a nitrogen atom, and a sulfur atom, and Z 7B Part of the -CH 2 - of 7B may also be substituted with a group containing at least one selected from an oxygen atom, a nitrogen atom, and a sulfur atom, and as a result, it may contain a hydroxyl group, an ester bond, an ether bond, an amide bond, a urethane bond, a urea bond, etc.

[0288] In formulas (f4) and (f5), Z 8 is a single bond, an ether bond, an ester bond, a thioether bond, or an alkanediyl group having 1 to 6 carbon atoms.

[0289] In formula (f5), Z 9 is a trivalent organic group having 1 to 12 carbon atoms and may also have at least one selected from an oxygen atom, a nitrogen atom, and a sulfur atom. Z 9The trivalent organic group represented may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include groups obtained by further removing one hydrogen atom from an alkylene group having 1 to 12 carbon atoms. Specific examples of the alkylene group having 1 to 12 carbon atoms include those having 1 to 12 carbon atoms among the alkylene groups having 1 to 24 carbon atoms described above. Also, Z 9 part or all of the hydrogen atoms may also be substituted with a group containing at least one selected from an oxygen atom, a nitrogen atom, and a sulfur atom, and Z 9 part of the -CH 2 - may also be substituted with a group containing at least one selected from an oxygen atom, a nitrogen atom, and a sulfur atom, and as a result, it may contain a hydroxyl group, an ester bond, an ether bond, an amide bond, a urethane bond, a urea bond, etc.

[0290] In formulas (f1) to (f5), R 21 to R 25 are each independently a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms which may contain a heteroatom. Specific examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. The hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include the same examples as those of the hydrocarbon groups exemplified in the description of formula (1) as R 2 to R 4 . Also, part or all of the hydrogen atoms of the hydrocarbon group may be substituted with a group containing a heteroatom such as an oxygen atom, a sulfur atom, a nitrogen atom, a halogen atom, etc., and part of the -CH 2 - of the hydrocarbon group may also be substituted with a group containing a heteroatom such as an oxygen atom, a sulfur atom, a nitrogen atom, etc., and as a result, it may contain a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a nitro group, a carbonyl group, an ether bond, an ester bond, a sulfonate ester bond, a carbonate ester bond, a lactone ring, a sultone ring, a carboxylic anhydride (-C(=O)-O-C(=O)-), a haloalkyl group, etc. In addition, R 23 and R 24 may also be bonded to each other and form a ring together with the sulfur atom to which they are bonded. At this time, specific examples of the ring include the same examples as those of the rings that can be formed when R 2 and R 3 are bonded to each other and form a ring together with the sulfur atom to which they are bonded as exemplified in the description of formula (a).

[0291] In formulas (f4) and (f5), R 26 are each independently a saturated hydrocarbon group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a fluorine atom, an iodine atom, a trifluoromethoxy group, a difluoromethoxy group, a cyano group, or a nitro group.

[0292] In formulas (f4) and (f5), the cyclic R is a (j + 2)-valent aromatic hydrocarbon group having 6 to 10 carbon atoms. Specific examples of the aforementioned (j + 2)-valent aromatic hydrocarbon group include groups obtained by removing (j + 2) hydrogen atoms from aromatic hydrocarbons such as benzene and naphthalene.

[0293] In formulas (f4) and (f5), j is independently an integer of 0 to 5.

[0294] In formula (f1), M - is a non-nucleophilic counter ion. Specific examples of the aforementioned non-nucleophilic counter ion include: halide ions such as chloride ion and bromide ion; fluoroalkylsulfonate ions such as trifluoromethanesulfonate ion, 1,1,1-trifluoroethanesulfonate ion, and nonafluorobutanesulfonate ion; arylsulfonate ions such as toluenesulfonate ion, benzenesulfonate ion, 4-fluorobenzenesulfonate ion, and 1,2,3,4,5-pentafluorobenzenesulfonate ion; alkylsulfonate ions such as methanesulfonate ion and butanesulfonate ion; imide ions such as bis(trifluoromethylsulfonyl)imide ion, bis(perfluoroethylsulfonyl)imide ion, and bis(perfluorobutylsulfonyl)imide ion; methylation ions such as tris(trifluoromethylsulfonyl)methylation ion and tris(perfluoroethylsulfonyl)methylation ion.

[0295] More specific examples of the aforementioned non-nucleophilic counter ion include: sulfonate ions in which the α-position is substituted with a fluorine atom represented by the following formula (f1-1), sulfonate ions in which the α-position is substituted with a fluorine atom and the β-position is substituted with a trifluoromethyl group represented by the following formula (f1-2), and the like.

[0296] [Chemical formula 79]

[0297]

[0298] In formula (f1-1), R 31 is a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and the hydrocarbon group may also contain at least one selected from an ether bond, an ester bond, a carbonyl group, a lactone ring, and a fluorine atom. The aforementioned hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include the same examples as those of the hydrocarbon group represented by R fa1 shown in formula (2A’) described later.

[0299] In formula (f1-2), R 32 is a hydrogen atom, a hydrocarbon group having 1 to 30 carbon atoms, or a hydrocarbon group carbonyl having 2 to 30 carbon atoms, and the hydrocarbon group and the hydrocarbon group carbonyl may also contain at least one selected from an ether bond, an ester bond, a carbonyl group, and a lactone ring. The hydrocarbon moiety of the aforementioned hydrocarbon group and hydrocarbon group carbonyl may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include the same examples as those of the hydrocarbon group represented by R fa1 shown in formula (2A’) described later.

[0300] Specific examples of the cation of the monomer providing the repeating unit f1 are as follows, but are not limited thereto. Further, in the following formula, R A is the same as described above.

[0301] [Chemical formula 80]

[0302]

[0303] Specific examples of the cations of the repeating units f2 to f5 can be exemplified by the same examples as those of the cation of the sulfonium salt represented by the formula (1).

[0304] Specific examples of the anion of the monomer providing the repeating unit f2 are as follows, but are not limited thereto. Further, in the following formula, R A is the same as described above.

[0305] [Chemical formula 81]

[0306]

[0307] [Chemical formula 82]

[0308]

[0309] [Chemical formula 83]

[0310]

[0311] [Chemical formula 84]

[0312]

[0313] [Chemical formula 85]

[0314]

[0315] [Chemical formula 86]

[0316]

[0317] [Chemical formula 87]

[0318]

[0319] [Chemical formula 88]

[0320]

[0321] [Chemical formula 89]

[0322]

[0323] [Chemical formula 90]

[0324]

[0325] [Chemical formula 91]

[0326]

[0327] [Chemical formula 92]

[0328]

[0329] [Chemical formula 93]

[0330]

[0331] [Chemical formula 94]

[0332]

[0333] [Chemical formula 95]

[0334]

[0335] Specific examples of the anion of the monomer providing the repeating unit f3 are as follows, but are not limited thereto. In addition, in the following formula, R A is the same as described above.

[0336] [Chemical formula 96]

[0337]

[0338] Specific examples of the anion of the monomer providing the repeating unit f4 or f5 are as follows, but are not limited thereto. In addition, in the following formula, R A and X BI are the same as described above.

[0339] [Chemical formula 97]

[0340]

[0341] [Chemical formula 98]

[0342]

[0343] [Chemical formula 99]

[0344]

[0345] [Chemical formula 100]

[0346]

[0347] [Chemical formula 101]

[0348]

[0349] [Chemical 102]

[0350]

[0351] [Chemical 103]

[0352]

[0353] [Chemical 104]

[0354]

[0355] [Chemical 105]

[0356]

[0357] [Chemical 106]

[0358]

[0359] [Chemical 107]

[0360]

[0361] [Chemical 108]

[0362]

[0363] [Chemical 109]

[0364]

[0365] [Chemical 110]

[0366]

[0367] [Chemical 111]

[0368]

[0369] [Chemical 112]

[0370]

[0371] [Chemical 113]

[0372]

[0373] [Chemical 114]

[0374]

[0375] [Chemical 115]

[0376]

[0377] [Chemical 116]

[0378]

[0379] [Chemical Formula 117]

[0380]

[0381] [Chemical Formula 118]

[0382]

[0383] [Chemical Formula 119]

[0384]

[0385] [Chemical Formula 120]

[0386]

[0387] [Chemical Formula 121]

[0388]

[0389] The repeating units f1 to f5 function as an acid generator. By bonding the acid generator to the polymer main chain, acid diffusion can be reduced, and a decrease in resolution caused by the blur of acid diffusion can be prevented. Further, by uniformly dispersing the acid generator, LWR and CDU are improved. In addition, when using a base polymer containing the repeating units f1 to f5 (i.e., a polymer-bonded acid generator), the blending of the additive acid generator described later can be omitted.

[0390] The base polymer for a positive resist material needs to contain the repeating unit a1 or a2 having an acid-labile group. At this time, the content ratios of the repeating units a1, a2, b, c, d, e, and f are preferably 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, more preferably 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, and still more preferably 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 f5, f = f1 + f2 + f3 + f4 + f5. Also, a1 + a2 + b + c + d + e + f = 1.0.

[0391] On the other hand, for the base polymer used in the negative resist material, acid-labile groups are not necessary. Such base polymers may 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 are preferably 0 < b ≤ 1.0, 0 ≤ c ≤ 0.9, 0 ≤ d ≤ 0.8, 0 ≤ e ≤ 0.8, and 0 ≤ f ≤ 0.5, more preferably 0.2 ≤ b ≤ 1.0, 0 ≤ c ≤ 0.8, 0 ≤ d ≤ 0.7, 0 ≤ e ≤ 0.7, and 0 ≤ f ≤ 0.4, and even more preferably 0.3 ≤ b ≤ 1.0, 0 ≤ c ≤ 0.75, 0 ≤ d ≤ 0.6, 0 ≤ e ≤ 0.6, and 0 ≤ f ≤ 0.3. Additionally, when the repeating unit f is at least one selected from the repeating units f1 to f5, f = f1 + f2 + f3 + f4 + f5. Also, b + c + d + e + f = 1.0.

[0392] Examples of the method for synthesizing the aforementioned base polymer include, for example, a method of adding a radical polymerization initiator and heating in an organic solvent the monomers that provide the aforementioned repeating units to carry out polymerization.

[0393] Specific examples of the organic solvent used in the polymerization include toluene, benzene, tetrahydrofuran (THF), diethyl ether, dioxane, propylene glycol monomethyl ether, γ-butyrolactone, and their mixed solvents, etc. Specific 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 is preferably 50 to 80 °C. The reaction time is preferably 2 to 100 hours, more preferably 5 to 20 hours.

[0394] When copolymerizing a hydroxyl group-containing monomer, the hydroxyl group can be replaced with an acetal group such as ethoxyethoxy that is easily deprotected by an acid in advance during polymerization, and deprotection can be carried out using a weak acid and water after polymerization. Alternatively, it can be replaced with an acetyl group, a formyl group, a trimethylacetyl group, etc. in advance, and base hydrolysis can be carried out after polymerization.

[0395] When copolymerizing hydroxystyrene and hydroxyvinylnaphthalene, hydroxystyrene and hydroxyvinylnaphthalene can also be replaced with acetoxystyrene and acetoxyvinylnaphthalene, and after polymerization, the acetoxy group can be deprotected by the aforementioned base hydrolysis to become hydroxystyrene and hydroxyvinylnaphthalene.

[0396] The base used in the base hydrolysis can be ammonia water, triethylamine, etc. Also, the reaction temperature is preferably -20 to 100 °C, more preferably 0 to 60 °C. The reaction time is preferably 0.2 to 100 hours, more preferably 0.5 to 20 hours.

[0397] The polystyrene equivalent weight average molecular weight (Mw) of the foregoing base polymer as determined by gel permeation chromatography (GPC) using THF as a solvent is preferably from 1,000 to 500,000, more preferably from 2,000 to 30,000. If Mw is within the foregoing range, the heat resistance of the resist film and the solubility in an alkali developing solution are good.

[0398] Also, in the foregoing base polymer, when the molecular weight distribution (Mw / Mn) is broad, since there are low molecular weight and high molecular weight polymers, there is a concern that foreign matter may be observed in the pattern and the shape of the pattern may deteriorate after exposure. As the pattern rule is miniaturized, the influence of Mw and Mw / Mn also tends to increase. Therefore, in order to obtain a resist material that can be ideally used for a fine pattern size, the Mw / Mn of the foregoing base polymer is preferably from 1.0 to 2.0, and a narrow dispersion of from 1.0 to 1.5 is particularly preferred.

[0399] In order to obtain a narrow dispersion polymer, not only ordinary radical polymerization but also living radical polymerization can be used. Specific examples of living radical polymerization include: Nitroxide-Mediated radical Polymerization (NMP) using a nitroxide radical, Atom Transfer Radical Polymerization (ATRP), Reversible Addition-Fragmentation chain Transfer (RAFT) polymerization, and the like.

[0400] The foregoing base polymer may also contain two or more polymers having different composition ratios, Mw, and Mw / Mn.

[0401] [Acid generator]

[0402] The resist material of the present invention may also contain an acid generator that generates a strong acid (hereinafter also referred to as an additive type acid generator). Here, a strong acid means a compound having an acidity sufficient to cause a deprotection reaction of an acid-labile group of a base polymer in the case of a chemically amplified positive resist material, and a compound having an acidity sufficient to cause a polarity change reaction or a crosslinking reaction due to an acid in the case of a chemically amplified negative resist material. By containing such an acid generator, the sulfonium salt represented by the foregoing formula (1) can function as a quencher, and the resist material of the present invention can function as a chemically amplified positive resist material or a chemically amplified negative resist material.

[0403] Examples of the aforementioned acid generators include compounds (photoacid generators) that generate acids upon exposure to actinic rays or radiation. If the photoacid generator is a compound that generates an acid upon irradiation with high-energy rays, any such compound is acceptable, and those that generate sulfonic acid, imidic acid, or methylated acid are preferred. Ideal photoacid generators include sulfonium salts, iodonium salts, sulfonyl diazomethanes, N-sulfonyloxyimides, oxime-O-sulfonate type acid generators, and the like. Specific examples of photoacid generators include those described in paragraphs

[0122] to

[0142] of Japanese Patent Laid-Open No. 2008-111103.

[0404] Furthermore, sulfonium salts represented by the following formula (2-1) and iodonium salts represented by the following formula (2-2) are preferably used as the photoacid generator.

[0405] [Chemical Formula 122]

[0406]

[0407] In formulae (2-1) and (2-2), R 101 ~R 105 are each independently a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms which may contain a heteroatom. Specific examples of the aforementioned halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like. The aforementioned hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include the same examples as those exemplified as the hydrocarbon groups represented by R 2 ~R 4 in the description of formula (1). Furthermore, a part or all of the hydrogen atoms of the aforementioned hydrocarbon group may be substituted with a group containing a heteroatom such as an oxygen atom, a sulfur atom, a nitrogen atom, or a halogen atom, and a part of -CH 2 - of the aforementioned hydrocarbon group may be substituted with a group containing a heteroatom such as an oxygen atom, a sulfur atom, or a nitrogen atom, and as a result, it may contain a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a nitro group, a carbonyl group, an ether bond, an ester bond, a sulfonate bond, a carbonate bond, a lactone ring, a sultone ring, a carboxylic anhydride, a haloalkyl group, and the like. In addition, R 101 and R 102 may be bonded to each other to form a ring together with the sulfur atom to which they are bonded. At this time, specific examples of the aforementioned ring include the same examples as those exemplified as the rings that can be formed by R 2 and R 3 being bonded to each other and forming a ring together with the sulfur atom to which they are bonded in the description of formula (1).

[0408] Specific examples of the cation of the sulfonium salt represented by formula (2-1) include the same examples as those exemplified as the cation of the sulfonium salt represented by formula (1).

[0409] Specific examples of the cation of the iodonium salt represented by formula (2-2) include those shown below, but are not limited thereto.

[0410] [Chemical formula 123]

[0411]

[0412] [Chemical formula 124]

[0413]

[0414] In formulas (2-1) and (2-2), Xa - is an anion selected from the following formulas (2A) to (2D).

[0415] [Chemical formula 125]

[0416]

[0417] In formula (2A), R fa is a fluorine atom or a hydrocarbon group having 1 to 40 carbon atoms which may also contain a heteroatom. The aforementioned hydrocarbon group may be saturated or unsaturated, and may be linear, branched or cyclic. Specific examples thereof may be listed and exemplified as the same examples as the hydrocarbon group represented by R fa1 shown below.

[0418] The anion represented by formula (2A) is preferably the one represented by the following formula (2A’).

[0419] [Chemical formula 126]

[0420]

[0421] In formula (2A’), R HF is a hydrogen atom or a trifluoromethyl group, and is preferably a trifluoromethyl group. R fa1 is a hydrocarbon group having 1 to 38 carbon atoms which may also contain a heteroatom. The aforementioned heteroatom is preferably an oxygen atom, a nitrogen atom, a sulfur atom, a halogen atom, etc., and more preferably an oxygen atom. From the viewpoint of obtaining high resolution in fine pattern formation, the aforementioned hydrocarbon group is particularly preferably one having 6 to 30 carbon atoms.

[0422] R fa1The represented hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples include, considering obtaining high resolution in fine pattern formation: alkyl groups having 1 to 38 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, pentyl, neopentyl, hexyl, heptyl, 2-ethylhexyl, nonyl, undecyl, tridecyl, pentadecyl, heptadecyl, icosyl, etc., with those having 6 to 30 carbon atoms being particularly preferred; cyclic saturated hydrocarbon groups having 3 to 38 carbon atoms such as cyclopentyl, cyclohexyl, 1-adamantyl, 2-adamantyl, 1-adamantylmethyl, norbornyl, norbornylmethyl, tricyclodecyl, tetracyclododecyl, tetracyclododecylmethyl, dicyclohexylmethyl, etc.; unsaturated aliphatic hydrocarbon groups having 2 to 38 carbon atoms such as allyl, 3-cyclohexenyl, etc.; aryl groups having 6 to 38 carbon atoms such as phenyl, 1-naphthyl, 2-naphthyl, etc.; aralkyl groups having 7 to 38 carbon atoms such as benzyl, diphenylmethyl, etc.; groups obtained by combining them, etc.

[0423] Also, part or all of the hydrogen atoms of the aforementioned hydrocarbon group may be substituted with a group containing a heteroatom such as an oxygen atom, a sulfur atom, a nitrogen atom, a halogen atom, etc., and part of the -CH 2 - of the aforementioned hydrocarbon group may also be substituted with a group containing a heteroatom such as an oxygen atom, a sulfur atom, a nitrogen atom, etc., and as a result, it may contain a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a nitro group, a carbonyl group, an ether bond, an ester bond, a sulfonate bond, a carbonate bond, a lactone ring, a sultone ring, a carboxylic anhydride (-C(=O)-O-C(=O)-), a haloalkyl group, etc. Specific examples of the heteroatom-containing hydrocarbon group include: tetrahydrofuranyl, methoxymethyl, ethoxymethyl, methylthiomethyl, acetamidomethyl, trifluoroethyl, (2-methoxyethoxy)methyl, acetoxymethyl, 2-carboxy-1-cyclohexyl, 2-oxopropyl, 4-oxo-1-adamantyl, 3-oxocyclohexyl, etc.

[0424] Regarding the synthesis of the sulfonium salt containing the anion represented by formula (2A'), refer to Japanese Patent Application Laid-Open No. 2007-145797, Japanese Patent Application Laid-Open No. 2008-106045, Japanese Patent Application Laid-Open No. 2009-7327, Japanese Patent Application Laid-Open No. 2009-258695, etc. Also, the sulfonium salts described in Japanese Patent Application Laid-Open No. 2010-215608, Japanese Patent Application Laid-Open No. 2012-41320, Japanese Patent Application Laid-Open No. 2012-106986, Japanese Patent Application Laid-Open No. 2012-153644, etc. can be appropriately used.

[0425] Specific examples of the anion represented by formula (2A) can be listed and exemplified as the same as those of the anion represented by formula (1A) in Japanese Patent Application Laid-Open No. 2018-197853.

[0426] In formula (2B), R fb1 and Rfb2 Each independently is a fluorine atom or a hydrocarbon group having 1 to 40 carbon atoms which may also contain a heteroatom. The aforementioned hydrocarbon group may be saturated or unsaturated, and may be any of linear, branched, and cyclic. Specific examples thereof may be cited and illustrated as the hydrocarbon group represented by R in formula (2A’). fa1 The same examples as the hydrocarbon group represented by R fb1 and R fb2 are preferably a fluorine atom or a linear fluorinated alkyl group having 1 to 4 carbon atoms. Also, R fb1 and R fb2 may also be bonded to each other and together with the group to which they are bonded (-CF 2 -SO 2 -N - -SO 2 -CF 2 -) form a ring. At this time, the group obtained by bonding R fb1 and R fb2 to each other is preferably a fluoroethylene or fluoropropylene group.

[0427] In formula (2C), R fc1 , R fc2 and R fc3 each independently is a fluorine atom or a hydrocarbon group having 1 to 40 carbon atoms which may also contain a heteroatom. The aforementioned hydrocarbon group may be saturated or unsaturated, and may be any of linear, branched, and cyclic. Specific examples thereof may be cited and illustrated as the hydrocarbon group represented by R fa1 in formula (2A’). fc1 , R fc2 and R fc3 are preferably a fluorine atom or a linear fluorinated alkyl group having 1 to 4 carbon atoms. Also, R fc1 and R fc2 may also be bonded to each other and together with the group to which they are bonded (-CF 2 -SO 2 -C - -SO 2 -CF 2 -) form a ring. At this time, the group obtained by bonding R fc1 and R fc2 to each other is preferably a fluoroethylene or fluoropropylene group.

[0428] In formula (2D), R fd is a hydrocarbon group having 1 to 40 carbon atoms which may also contain a heteroatom. The aforementioned hydrocarbon group may be saturated or unsaturated, and may be any of linear, branched, and cyclic. Specific examples thereof may be cited and illustrated as the hydrocarbon group represented by R fa1 in formula (2A’).

[0429] Regarding the synthesis of sulfonium salts containing anions represented by formula (2D), refer to Japanese Patent Application Laid-Open No. 2010-215608 and Japanese Patent Application Laid-Open No. 2014-133723 for details.

[0430] Specific examples of the anions represented by formula (2D) can be enumerated and exemplified as those similar to the anions represented by formula (1D) in Japanese Patent Application Laid-Open No. 2018-197853.

[0431] In addition, the photoacid generator containing an anion represented by formula (2D) does not have a fluorine atom at the α-position of the sulfo group but has two trifluoromethyl groups at the β-position, and thus has an acidity sufficient to cleave acid-labile groups in the base polymer. Therefore, it can be used as a photoacid generator.

[0432] A photoacid generator represented by the following formula (3) can also be desirably used.

[0433] [Chemical Formula 127]

[0434]

[0435] In formula (3), R 201 and R 202 are each independently a halogen atom or a hydrocarbon group having 1 to 30 carbon atoms which may contain a heteroatom. R 203 is an alkylene group having 1 to 30 carbon atoms which may contain a heteroatom. Further, any two of R 201 , R 202 and R 203 may be bonded to each other and together with the sulfur atom to which they are bonded form a ring. At this time, specific examples of the aforementioned ring can be enumerated as those similar to the rings that can be formed by bonding R 2 and R 3 and together with the sulfur atom to which they are bonded as exemplified in the description of formula (1).

[0436] R 201 and R 202 The hydrocarbon groups represented by may be saturated or unsaturated and may be linear, branched, or cyclic. Specific examples thereof include alkyl groups having 1 to 30 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, tert-pentyl, n-hexyl, n-octyl, 2-ethylhexyl, n-nonyl, n-decyl; cyclopentyl, cyclohexyl, cyclopentylmethyl, cyclopentylethyl, cyclopentylbutyl, cyclohexylmethyl, cyclohexylethyl, cyclohexylbutyl, norbornyl, oxanorbornanyl, tricyclo[5.2.1.0 2,6Cyclic saturated hydrocarbon groups having 3 to 30 carbon atoms such as decyl and adamantyl; aryl groups having 6 to 30 carbon atoms such as phenyl, methylphenyl, ethylphenyl, n-propylphenyl, isopropylphenyl, n-butylphenyl, isobutylphenyl, sec-butylphenyl, tert-butylphenyl, naphthyl, methylnaphthyl, ethylnaphthyl, n-propylnaphthyl, isopropylnaphthyl, n-butylnaphthyl, isobutylnaphthyl, sec-butylnaphthyl, tert-butylnaphthyl, anthryl, etc.; groups obtained by combining them, etc. Further, a part or all of the hydrogen atoms of the aforementioned hydrocarbon group may also be substituted with a group containing a heteroatom such as an oxygen atom, a sulfur atom, a nitrogen atom, or a halogen atom, and a part of -CH 2 - of the aforementioned hydrocarbon group may also be substituted with a group containing a heteroatom such as an oxygen atom, a sulfur atom, or a nitrogen atom, and as a result, it may also contain a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a nitro group, a carbonyl group, an ether bond, an ester bond, a sulfonate bond, a carbonate bond, a lactone ring, a sultone ring, a carboxylic anhydride (-C(=O)-O-C(=O)-), a haloalkyl group, etc.

[0437] R 203 The alkylene group represented may be saturated or unsaturated and may be linear, branched, or cyclic. Specific examples thereof include: methanediyl, ethane-1,1-diyl, ethane-1,2-diyl, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, decane-1,10-diyl, undecane-1,11-diyl, dodecane-1,12-diyl, tridecane-1,13-diyl, tetradecane-1,14-diyl, pentadecane-1,15-diyl, hexadecane-1,16-diyl, heptadecane-1,17-diyl, etc., alkane diyl groups having 1 to 30 carbon atoms; cyclopentane diyl, cyclohexane diyl, norbornane diyl, adamantane diyl, etc., cyclic saturated alkylene groups having 3 to 30 carbon atoms; phenylene, methylene phenyl, ethylene phenyl, n-propylene phenyl, isopropyl phenyl, n-butylene phenyl, isobutylene phenyl, sec-butylene phenyl, tert-butylene phenyl, naphthylene, methylene naphthyl, ethylene naphthyl, n-propylene naphthyl, isopropyl naphthyl, n-butylene naphthyl, isobutylene naphthyl, sec-butylene naphthyl, tert-butylene naphthyl, etc., arylene groups having 6 to 30 carbon atoms; groups obtained by combining them, etc. Further, a part or all of the hydrogen atoms of the aforementioned alkylene group may also be substituted with a group containing a heteroatom such as an oxygen atom, a sulfur atom, a nitrogen atom, or a halogen atom, and a part of -CH 2 - of the aforementioned alkylene group may also be substituted with a group containing a heteroatom such as an oxygen atom, a sulfur atom, or a nitrogen atom, and as a result, it may also contain a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a nitro group, a carbonyl group, an ether bond, an ester bond, a sulfonate bond, a carbonate bond, a lactone ring, a sultone ring, a carboxylic anhydride (-C(=O)-O-C(=O)-), a haloalkyl group, etc. The aforementioned heteroatom is preferably an oxygen atom.

[0438] In formula (3), L C is a single bond, an ether bond, or an alkylene group having 1 to 20 carbon atoms which may also contain a heteroatom. The aforementioned alkylene group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof may be listed and exemplified as the alkylene group represented by R 203 the same examples as those of the alkylene group represented.

[0439] In formula (3), X A , X B , X C and X D are each independently a hydrogen atom, a fluorine atom, or a trifluoromethyl group. However, at least one of X A , X B , X C and X D is a fluorine atom or a trifluoromethyl group.

[0440] In formula (3), k is an integer from 0 to 3.

[0441] The photoacid generator represented by formula (3) is preferably the one represented by the following formula (3’).

[0442] [Chemical formula 128]

[0443]

[0444] In formula (3’), L C is the same as the aforementioned one. X E is a hydrogen atom or a trifluoromethyl group, and is preferably a trifluoromethyl group. R 301 , R 302 and R 303 are each independently a hydrogen atom, or a hydrocarbon group having 1 to 20 carbon atoms which may also contain a heteroatom. The aforementioned hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof may be listed and exemplified as the hydrocarbon group represented by R fa1 in formula (2A’). x and y are each independently an integer from 0 to 5, and z is an integer from 0 to 4.

[0445] Specific examples of the photoacid generator represented by formula (3) may be listed and are the same as those exemplified as the photoacid generator represented by formula (2) in Japanese Patent Laid-Open No. 2017-026980.

[0446] Among the aforementioned photoacid generators, those containing an anion represented by formula (2A’) or (2D) have small acid diffusion and excellent solubility in solvents, and are particularly ideal. Also, those represented by formula (3’) have extremely small acid diffusion and are particularly ideal.

[0447] The aforementioned photoacid generator may also use a sulfonium salt or an iodonium salt containing an anion having an aromatic ring substituted with an iodine atom or a bromine atom. Specific examples of such salts include those represented by the following formula (4-1) or (4-2).

[0448] [Chemical formula 129]

[0449]

[0450] In formula (4-1) and (4-2), p is an integer satisfying 1 ≤ p ≤ 3. q and r are integers satisfying 1 ≤ q ≤ 5, 0 ≤ r ≤ 3, and 1 ≤ q + r ≤ 5. q is preferably an integer satisfying 1 ≤ q ≤ 3, more preferably 2 or 3. r is preferably an integer satisfying 0 ≤ r ≤ 2.

[0451] In formula (4-1) and (4-2), X BI is an iodine atom or a bromine atom. When p and / or q is 2 or more, they may be the same or different from each other.

[0452] In formula (4-1) and (4-2), L 1 is a single bond, an ether bond, an ester bond, or a saturated alkylene group having 1 to 6 carbon atoms that may also contain an ether bond or an ester bond. The aforementioned saturated alkylene group may be linear, branched, or cyclic.

[0453] In formula (4-1) and (4-2), L 2 is a single bond or a divalent linking group having 1 to 20 carbon atoms when p is 1, and a (p + 1)-valent linking group having 1 to 20 carbon atoms when p is 2 or 3, and the linking group may also contain an oxygen atom, a sulfur atom, or a nitrogen atom.

[0454] In formula (4-1) and (4-2), R 401 is a hydroxyl group, a carboxyl group, a fluorine atom, a chlorine atom, a bromine atom, or an amino group, or a hydrocarbon group having 1 to 20 carbon atoms, a 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 20 carbon atoms, a hydrocarbon carbonyloxy group having 2 to 20 carbon atoms, or a hydrocarbon sulfonyloxy group having 1 to 20 carbon atoms that may also contain a fluorine atom, a chlorine atom, a bromine atom, a hydroxyl group, an amino group, or an ether bond, or -N(R 401A )(R 401B ), -N(R 401C )-C(=O)-R 401D or -N(R 401C )-C(=O)-O-R 401D . R 401A and R 401B are each independently a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms. R 401Cis 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 oxy group having 1 to 6 carbon atoms, a saturated hydrocarbon group carbonyl group having 2 to 6 carbon atoms, or a saturated hydrocarbon group carbonyl oxy group having 2 to 6 carbon atoms. R 401D is an aliphatic hydrocarbon group having 1 to 16 carbon atoms, an aryl group having 6 to 14 carbon atoms, or an aralkyl group having 7 to 15 carbon atoms, and may also contain a halogen atom, a hydroxyl group, a saturated hydrocarbon group oxy group having 1 to 6 carbon atoms, a saturated hydrocarbon group carbonyl group having 2 to 6 carbon atoms, or a saturated hydrocarbon group carbonyl oxy group having 2 to 6 carbon atoms. The aforementioned aliphatic hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. The aforementioned hydrocarbon group, hydrocarbon group oxy group, hydrocarbon group carbonyl group, hydrocarbon group oxycarbonyl group, hydrocarbon group carbonyl oxy group, and hydrocarbon group sulfonyl oxy group may be linear, branched, or cyclic. When p and / or r is 2 or more, each R 401 may be the same as or different from each other.

[0455] Among them, R 401 is preferably a hydroxyl group, -N(R 401C )-C(=O)-R 401D , -N(R 401C )-C(=O)-O-R 401D , a fluorine atom, a chlorine atom, a bromine atom, a methyl group, a methoxy group, etc.

[0456] In formulas (4-1) and (4-2), Rf 1 ~Rf 4 are each independently a hydrogen atom, a fluorine atom, or a trifluoromethyl group, but at least one of them is a fluorine atom or a trifluoromethyl group. Also, Rf 1 and Rf 2 may also combine to form a carbonyl group. It is particularly preferred that both Rf 3 and Rf 4 are fluorine atoms.

[0457] In formulas (4-1) and (4-2), R 402 ~R 406 are each independently a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms which may also contain a hetero atom. Specific examples of the aforementioned halogen atom include: a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. The aforementioned hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include the same examples as those exemplified in the description of formula (1) as the hydrocarbon group represented by R 2 ~R 4 . Also, a part or all of the hydrogen atoms of the aforementioned hydrocarbon group may be substituted with a hydroxyl group, a carboxyl group, a halogen atom, a cyano group, a nitro group, a mercapto group, a sultone ring, a sulfo group, or a group containing a sulfonium salt, and a part of -CH 2 - of the aforementioned hydrocarbon group may be substituted with an ether bond, an ester bond, a carbonyl group, an amide bond, a carbonate bond, or a sulfonate bond. In addition, R 402 and R403 They can also be bonded to each other and together with the sulfur atoms to which they are bonded form a ring. At this time, specific examples of the aforementioned ring can be the same as those exemplified in the description of formula (1) as R 2 and R 3 and the rings that can be formed together with the sulfur atoms to which they are bonded.

[0458] Specific examples of the cation of the sulfonium salt represented by formula (4-1) can be the same as those exemplified as the cation of the sulfonium salt represented by formula (1). Also, specific examples of the cation of the oxosulfonium salt represented by formula (4-2) can be the same as those exemplified as the cation of the oxosulfonium salt represented by formula (2-2).

[0459] Specific examples of the anion of the onium salt represented by formula (4-1) or (4-2) are as shown below, but are not limited thereto. In addition, in the following formula, X BI is the same as the aforementioned.

[0460] [Chemical formula 130]

[0461]

[0462] [Chemical formula 131]

[0463]

[0464] [Chemical formula 132]

[0465]

[0466] [Chemical formula 133]

[0467]

[0468] [Chemical formula 134]

[0469]

[0470] [Chemical formula 135]

[0471]

[0472] [Chemical formula 136]

[0473]

[0474] [Chemical formula 137]

[0475]

[0476] [Chemical formula 138]

[0477]

[0478] [Chemical formula 139]

[0479]

[0480] [Chemical formula 140]

[0481]

[0482] [Chemical formula 141]

[0483]

[0484] [Chemical formula 142]

[0485]

[0486] [Chemical formula 143]

[0487]

[0488] [Chemical formula 144]

[0489]

[0490] [Chemical formula 145]

[0491]

[0492] [Chemical formula 146]

[0493]

[0494] [Chemical formula 147]

[0495]

[0496] [Chemical formula 148]

[0497]

[0498] [Chemical formula 149]

[0499]

[0500] [Chemical formula 150]

[0501]

[0502] [Chemical formula 151]

[0503]

[0504] [Chemical formula 152]

[0505]

[0506] The aforementioned photoacid generator may also be a sulfonium salt or an iodonium salt of fluorobenzenesulfonic acid bonded to iodobenzoic acid represented by the following formula (4-3) or (4-4).

[0507] [Chemical formula 153]

[0508]

[0509] In formula (4-3) and (4-4), s is an integer from 1 to 5. t is an integer from 0 to 3. u is an integer from 1 to 4.

[0510] In formula (4-3) and (4-4), R 411 is a hydroxyl group, a carboxyl group, an alkoxycarbonyl group, a fluorine atom, a chlorine atom, a bromine atom, an amino group, or a saturated hydrocarbon group with 1 to 20 carbon atoms, a saturated hydrocarbon group oxy with 1 to 20 carbon atoms, or a saturated hydrocarbon group carbonyl oxy with 2 to 20 carbon atoms that may also contain a fluorine atom, a chlorine atom, a bromine atom, a hydroxyl group, an amino group, or an alkoxy group, or -N(R 411A )-C(=O)-R 411B or -N(R 411A )-C(=O)-O-R 411B , and R 411A is a hydrogen atom or a saturated hydrocarbon group with 1 to 6 carbon atoms. R 411B is an aliphatic hydrocarbon group with 1 to 16 carbon atoms, an aryl group with 6 to 14 carbon atoms, or an aralkyl group with 7 to 15 carbon atoms, and may also contain a halogen atom, a hydroxyl group, a saturated hydrocarbon group oxy with 1 to 6 carbon atoms, a saturated hydrocarbon group carbonyl with 2 to 6 carbon atoms, or a saturated hydrocarbon group carbonyl oxy with 2 to 6 carbon atoms.

[0511] In formula (4-3) and (4-4), L 3 is a single bond or a divalent linking group with 1 to 20 carbon atoms, and this linking group may also contain an oxygen atom, a sulfur atom, or a nitrogen atom.

[0512] In formula (4-3) and (4-4), Rf 11 is a fluorine atom or a trifluoromethyl group.

[0513] In formula (4-3) and (4-4), R 412 ~R 416 are each independently a halogen atom, or a hydrocarbon group with 1 to 20 carbon atoms that may also contain a heteroatom. Specific examples of the aforementioned halogen atom include: a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. The aforementioned hydrocarbon group may be saturated or unsaturated, and may be any of linear, branched, or cyclic. Specific examples thereof can be listed as those exemplified in the description of formula (1) as R 2 ~R 4Examples of the same hydrocarbon groups represented. Also, part or all of the hydrogen atoms of the aforementioned hydrocarbon group may be substituted with a hydroxyl group, a carboxyl group, a halogen atom, a cyano group, a nitro group, a mercapto group, a sultone ring, a sulfo group, or a group containing a sulfonium salt, and part of the -CH 2 - of the aforementioned hydrocarbon group may also be substituted with an ether bond, an ester bond, a carbonyl group, an amide bond, a carbonate bond, or a sulfonate bond. In addition, R 402 and R 403 may also be bonded to each other and form a ring together with the sulfur atom to which they are bonded. In this case, specific examples of the aforementioned ring may include the same examples as those of the ring that can be formed by bonding to R 2 and R 3 and the sulfur atom to which they are bonded as exemplified in the description of formula (1).

[0514] Specific examples of the cation of the sulfonium salt represented by formula (4-3) may include the same examples as those exemplified for the cation of the sulfonium salt represented by formula (1). Specific examples of the cation of the oxosulfonium salt represented by formula (4-4) may include the same examples as those exemplified for the cation of the oxosulfonium salt represented by formula (2-2).

[0515] Specific examples of the anion of the onium salt represented by formula (4-3) or (4-4) are as follows, but are not limited thereto.

[0516] [Chemical formula 154]

[0517]

[0518] [Chemical formula 155]

[0519]

[0520] [Chemical formula 156]

[0521]

[0522] [Chemical formula 157]

[0523]

[0524] [Chemical formula 158]

[0525]

[0526] When the resist material of the present invention contains the aforementioned addition-type acid generator, its content is preferably 0.1 to 50 parts by mass, more preferably 1 to 40 parts by mass, relative to 100 parts by mass of the base polymer. The aforementioned addition-type acid generator may be used alone or in combination of two or more. In the resist material of the present invention, the aforementioned base polymer can function as a chemically amplified resist material by containing any one of the repeating units f1 to f5 and / or by containing an addition-type acid generator.

[0527] [Organic solvent]

[0528] The resist material of the present invention may also contain an organic solvent. If the aforementioned organic solvent can dissolve the aforementioned components and the following components, there is no particular limitation. Specific examples of the aforementioned organic solvent include: ketones such as cyclohexanone, cyclopentanone, methyl-2-n-pentyl ketone, 2-heptanone, etc. described in paragraphs

[0144] to

[0145] of JP-A-2008-111103; alcohols such as 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, diacetone alcohol, etc.; ethers such as propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol dimethyl ether, diethylene glycol dimethyl ether, etc.; 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 monoterbutyl ether acetate, etc.; lactones such as γ-butyrolactone, etc.

[0529] In the resist material of the present invention, the content of the aforementioned organic solvent is preferably 100 to 10,000 parts by mass, more preferably 200 to 8,000 parts by mass, relative to 100 parts by mass of the base polymer. The aforementioned organic solvent may be used alone or in combination of two or more.

[0530] [Other components]

[0531] In the resist material of the present invention, in addition to containing the aforementioned components, it may also contain a surfactant, a dissolution inhibitor, a crosslinking agent, a quencher other than the sulfonium salt represented by the formula (1) (hereinafter also referred to as other quenchers), a water repellency improver, acetylene alcohols, etc.

[0532] Specific examples of the aforementioned surfactant include those described in paragraphs

[0165] to

[0166] of JP-A-2008-111103. By adding a surfactant, the coatability of the resist material can be further improved or controlled. When the resist material of the present invention contains the aforementioned surfactant, its content is preferably 0.0001 to 10 parts by mass relative to 100 parts by mass of the base polymer. The aforementioned surfactant may be used alone or in combination of two or more.

[0533] When the resist material of the present invention is positive type, by blending a dissolution inhibitor, the dissolution rate difference between the exposed portion and the unexposed portion can be further enlarged, and the resolution can be further improved. Specific examples of the aforementioned dissolution inhibitor include: a compound in which the hydrogen atom of the phenolic hydroxyl group in a compound having a molecular weight of preferably 100 to 1000, more preferably 150 to 800, and containing two or more phenolic hydroxyl groups in the molecule is substituted by an acid-labile group in a proportion of 0 to 100 mol% as a whole, or a compound in which the hydrogen atom of the carboxyl group in a compound containing a carboxyl group in the molecule is substituted by an acid-labile group in a proportion of 50 to 100 mol% on average as a whole. Specific examples include: compounds obtained by substituting the hydrogen atoms of the hydroxyl groups and carboxyl groups of bisphenol A, triphenol, phenolphthalein, cresol novolak resin, naphthalene carboxylic acid, adamantane carboxylic acid, and cholic acid with acid-labile groups, etc., for example, those described in paragraphs

[0155] to

[0178] of Japanese Patent Laid-Open No. 2008-122932.

[0534] When the resist material of the present invention is positive type and contains the aforementioned dissolution inhibitor, its content is preferably 0 to 50 parts by mass, more preferably 5 to 40 parts by mass, based on 100 parts by mass of the base polymer. The aforementioned dissolution inhibitor can be used alone or in combination of two or more.

[0535] On the other hand, when the resist material of the present invention is negative type, by adding a crosslinking agent to reduce the dissolution rate of the exposed portion, a negative pattern can be obtained. Specific examples of the aforementioned crosslinking agent include: epoxy compounds substituted with at least one group selected from hydroxymethyl, alkoxymethyl, and acyloxymethyl, melamine compounds, guanamine compounds, glycoluril compounds or urea compounds, isocyanate compounds, azide compounds, compounds containing double bonds such as alkenyloxy groups, etc. They can be used in the form of additives or introduced as pendant groups into the polymer side chain. Also, compounds containing hydroxyl groups can be used as crosslinking agents.

[0536] Specific examples of the aforementioned epoxy compounds include: tris(2,3-epoxypropyl) isocyanurate, trimethylolmethane triglycidyl ether, trimethylolpropane triglycidyl ether, triethylolethane triglycidyl ether, etc.

[0537] Specific examples of the aforementioned melamine compounds include: hexamethoxymethyl melamine, hexamethoxymethyl melamine, compounds or mixtures in which 1 to 6 hydroxymethyl groups in hexamethoxymethyl melamine are methoxymethylated, hexamethoxyethyl melamine, hexaacyloxymethyl melamine, compounds or mixtures in which 1 to 6 hydroxymethyl groups in hexamethoxymethyl melamine are acyloxymethylated, etc.

[0538] Specific examples of the foregoing guanamine compounds include: tetramethylol guanamine, tetramethoxymethyl guanamine, compounds or mixtures thereof in which 1 to 4 hydroxymethyl groups in tetramethylol guanamine are methoxymethylated, tetramethoxyethyl guanamine, tetraacyloxy guanamine, compounds or mixtures thereof in which 1 to 4 hydroxymethyl groups in tetramethylol guanamine are acyloxymethylated, and the like.

[0539] Specific examples of the foregoing glycoluril compounds include: tetramethylol glycoluril, tetramethoxy glycoluril, tetramethoxymethyl glycoluril, compounds or mixtures thereof in which 1 to 4 hydroxymethyl groups in tetramethylol glycoluril are methoxymethylated, compounds or mixtures thereof in which 1 to 4 hydroxymethyl groups in tetramethylol glycoluril are acyloxymethylated, and the like. Specific examples of the foregoing urea compounds include: tetramethylol urea, tetramethoxymethyl urea, compounds or mixtures thereof in which 1 to 4 hydroxymethyl groups in tetramethylol urea are methoxymethylated, tetramethoxyethyl urea, and the like.

[0540] Specific examples of the foregoing isocyanate compounds include: tolylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, cyclohexane diisocyanate, and the like.

[0541] Specific examples of the foregoing azide compounds include: 1,1'-biphenyl-4,4'-bisazide, 4,4'-methylenebisazide, 4,4'-oxybisazide, and the like.

[0542] Specific examples of the foregoing compounds containing vinyloxy groups include: ethylene glycol divinyl ether, triethylene glycol divinyl ether, 1,2-propanediol divinyl ether, 1,4-butanediol divinyl ether, tetramethylene glycol divinyl ether, neopentyl glycol divinyl ether, trimethylolpropane trivinyl ether, hexanediol divinyl ether, 1,4-cyclohexanediol divinyl ether, pentaerythritol trivinyl ether, pentaerythritol tetravinyl ether, sorbitol tetravinyl ether, sorbitol pentavinyl ether, trimethylolpropane trivinyl ether, and the like.

[0543] When the resist material of the present invention is negative and contains the foregoing crosslinking agent, its content is preferably 0.1 to 50 parts by mass, more preferably 1 to 40 parts by mass, based on 100 parts by mass of the base polymer. The foregoing crosslinking agent can be used alone or in combination of two or more.

[0544] Specific examples of the other quenching agents described above may include basic compounds of known types. Specific examples of the basic compounds of known types may include: primary, secondary or tertiary aliphatic amines, mixed amines, aromatic amines, heterocyclic amines, nitrogen-containing compounds having a carboxyl group, nitrogen-containing compounds having a sulfonyl group, nitrogen-containing compounds having a hydroxyl group, nitrogen-containing compounds having a hydroxyphenyl group, alcoholic nitrogen-containing compounds, amides, imides, urethanes, etc. Particularly preferably, the primary, secondary, and tertiary amine compounds described in paragraphs

[0146] to

[0164] of Japanese Patent Laid-Open No. 2008-111103, amine compounds having a hydroxyl group, an ether bond, an ester bond, a lactone ring, a cyano group, a sulfonate bond, or compounds having a urethane group described in Japanese Patent No. 3790649 are particularly excellent. By adding such a basic compound, for example, the diffusion rate of acid in the resist film can be further suppressed, or the shape can be corrected.

[0545] Furthermore, other quenching agents may include sulfonium salts, iodonium salts, ammonium salts, etc. of sulfonic acids and carboxylic acids in which the α-position is not fluorinated, as described in Japanese Patent Laid-Open No. 2008-158339. Sulfonic acids, imidic acids, or methylated acids in which the α-position is fluorinated are necessary when deprotecting the acid labile group of the carboxylic acid ester, and by salt exchange with the iodonium salt in which the α-position is not fluorinated, a sulfonic acid or carboxylic acid in which the α-position is not fluorinated is released. Sulfonic acids and carboxylic acids in which the α-position is not fluorinated do not cause a deprotection reaction, so they function as quenching agents.

[0546] Other examples of other quenching agents may include polymer-type quenching agents described in Japanese Patent Laid-Open No. 2008-239918. It improves the rectangularity of the resist pattern by aligning on the surface of the resist film. The polymer-type quenching agent also has the effect of preventing film loss and pattern doming of the pattern when using a protective film for immersion exposure.

[0547] When the resist material of the present invention contains other quenching agents, the content thereof is preferably 0 to 5 parts by mass, more preferably 0 to 4 parts by mass, based on 100 parts by mass of the base polymer. The other quenching agents may be used alone or in combination of two or more.

[0548] The aforementioned water repellency improver is one that improves the water repellency of the surface of the resist film and can be used in immersion lithography without using a topcoat. The aforementioned water repellency improver is preferably a polymer containing a fluorinated alkyl group, a polymer containing 1,1,1,3,3,3 - hexafluoro - 2 - propanol residues with a specific structure, etc., and is more preferably exemplified in Japanese Patent Laid - Open No. 2007 - 297590, Japanese Patent Laid - Open No. 2008 - 111103, etc. The aforementioned water repellency improver must be soluble in an alkali developer and an organic solvent developer. The aforementioned specific water repellency improver having 1,1,1,3,3,3 - hexafluoro - 2 - propanol residues has good solubility in the developer. Regarding the water repellency improver, a polymer containing repeating units of amino groups and amine salts has a high effect of preventing the evaporation of acid during PEB and preventing the opening defect of the hole pattern after development. When the resist material of the present invention contains the aforementioned water repellency improver, its content is preferably 0 to 20 parts by mass, more preferably 0.5 to 10 parts by mass, based on 100 parts by mass of the base polymer. The aforementioned water repellency improver can be used alone or in combination of two or more kinds.

[0549] Specific examples of the aforementioned acetylene alcohols can be exemplified by the examples described in paragraphs

[0179] to

[0182] of Japanese Patent Laid - Open No. 2008 - 122932. When the resist material of the present invention contains the aforementioned acetylene alcohols, its content is preferably 0 to 5 parts by mass based on 100 parts by mass of the base polymer. The aforementioned acetylene alcohols can be used alone or in combination of two or more kinds.

[0550] [Pattern formation method]

[0551] When the resist material of the present invention is used in the manufacture of various integrated circuits, known lithography techniques can be used. For example, specific examples of the pattern formation method can include a method comprising the following steps:

[0552] Forming a resist film on a substrate using the aforementioned resist material,

[0553] Exposing the aforementioned resist film to high - energy rays, and

[0554] Developing the aforementioned exposed resist film using a developer.

[0555] First, the resist material of the present invention is coated on a substrate for integrated circuit manufacturing (Si, SiO 2 , SiN, SiON, TiN, WSi, BPSG, SOG, organic anti - reflection film, etc.) or a substrate for mask circuit manufacturing (Cr, CrO, CrON, MoSi 2 , SiO 2etc.). It is pre-baked on a hot plate at a temperature preferably of 60 to 150 °C for 10 seconds to 30 minutes, more preferably 80 to 120 °C for 30 seconds to 20 minutes, to form a resist film.

[0556] Then, the aforementioned resist film is exposed to high-energy rays. Specific examples of the aforementioned high-energy rays include: ultraviolet rays, far-ultraviolet rays, EB, EUV with a wavelength of 3 to 15 nm, X-rays, soft X-rays, excimer lasers, γ-rays, synchrotron radiation, etc. When the aforementioned high-energy rays use ultraviolet rays, far-ultraviolet rays, EUV, X-rays, soft X-rays, excimer lasers, γ-rays, synchrotron radiation, etc., directly or using a mask for forming a desired pattern, and the exposure dose is preferably about 1 to 200 mJ / cm 2 and more preferably about 10 to 100 mJ / cm 2 for irradiation. When the high-energy ray uses EB, the exposure dose is preferably about 0.1 to 300 μC / cm 2 and more preferably about 0.5 to 200 μC / cm 2 for direct writing or using a mask for forming a desired pattern. In addition, the resist material of the present invention is particularly suitable for fine patterning by KrF excimer laser, ArF excimer laser, EB, EUV, X-rays, soft X-rays, γ-rays, synchrotron radiation in high-energy rays, and is particularly suitable for fine patterning by EB or EUV.

[0557] It is also possible to perform PEB at a temperature preferably of 30 to 150 °C for 10 seconds to 30 minutes, more preferably 50 to 120 °C for 30 seconds to 20 minutes, on a hot plate or in an oven after exposure, or it may not be performed.

[0558] After exposure or after PEB, by using a developer of an alkaline aqueous solution such as tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, etc. preferably at 0.1 to 10% by mass, more preferably 2 to 5% by mass, and using conventional methods such as dip method, puddle method, spray method, etc., the exposed resist film is developed for 3 seconds to 3 minutes, preferably 5 seconds to 2 minutes, to form a desired pattern. In the case of a positive resist material, the irradiated part is dissolved in the developer, and the unexposed part is not dissolved, and a desired positive pattern is formed on the substrate. In the case of a negative resist material, it is the opposite of the case of the positive resist material, the irradiated part is not dissolved in the developer, and the unexposed part is dissolved.

[0559] Negative patterns can also be obtained by using a positive photoresist material containing a base polymer with acid-labile groups and developing it with an organic solvent. Specific examples of the developer used in this case include: 2-octanone, 2-nonanone, 2-heptanone, 3-heptanone, 4-heptanone, 2-hexanone, 3-hexanone, diisobutyl ketone, methylcyclohexanone, acetophenone, methylacetophenone, propyl acetate, butyl acetate, isobutyl acetate, amyl acetate, butenyl acetate, isoamyl acetate, propyl formate, butyl formate, isobutyl formate, amyl formate, isoamyl formate, methyl valerate, methyl pentenoate, methyl crotonate, ethyl crotonate, 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, phenethyl 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.

[0560] Rinsing is carried out at the end of development. The rinsing liquid should be a solvent that is miscible with the developer and does not dissolve the photoresist film. Such solvents can ideally be 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, etc.

[0561] Specific examples of the 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.

[0562] Specific examples of the ether compounds with 8 to 12 carbon atoms mentioned above 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.

[0563] Specific examples of the alkanes having 6 to 12 carbon atoms include: hexane, heptane, octane, nonane, decane, undecane, dodecane, methylcyclopentane, dimethylcyclopentane, cyclohexane, methylcyclohexane, dimethylcyclohexane, cycloheptane, cyclooctane, cyclononane, etc. Specific examples of the alkenes having 6 to 12 carbon atoms include: hexene, heptene, octene, cyclohexene, methylcyclohexene, dimethylcyclohexene, cycloheptene, cyclooctene, etc. Specific examples of the alkynes having 6 to 12 carbon atoms include: hexyne, heptyne, octyne, etc.

[0564] Specific examples of the aromatic solvents include: toluene, xylene, ethylbenzene, cumene, tert-butylbenzene, mesitylene, etc.

[0565] By performing rinsing, the collapse of the resist pattern and the occurrence of defects can be reduced. Also, rinsing is not necessary, and by not performing rinsing, the amount of solvent used can be reduced.

[0566] The developed hole pattern and groove pattern can also be shrunk using heat flow, RELACS technology, or DSA technology. A shrinkage agent is applied to the hole pattern, and due to the diffusion of the acid catalyst from the resist film during baking, crosslinking of the shrinkage agent is caused on the surface of the resist film, and the shrinkage agent adheres to the sidewalls of the hole pattern. The baking temperature should be 70 to 180 °C, more preferably 80 to 170 °C, and the baking time should be 10 to 300 seconds to remove the excess shrinkage agent and shrink the hole pattern.

[0567] [Examples]

[0568] Hereinafter, synthesis examples, examples, and comparative examples are exemplified to specifically illustrate the present invention, but the present invention is not limited to the following examples.

[0569] The structures of the quenching agents Q-1 to Q-16 used in the resist material are shown below.

[0570] [Chemical Formula 159]

[0571]

[0572] [Chemical Formula 160]

[0573]

[0574] [Synthesis Example] Synthesis of Basic Polymers (Polymers P-1 to P-4)

[0575] Each monomer combination was copolymerized in THF as a solvent, placed in methanol, and the precipitated solid was washed with hexane and then separated and dried to obtain basic polymers (polymers P-1 to P-4) having the following compositions. The compositions of the obtained basic polymers were determined using 1Confirmed by \(^1H\)-NMR, and \(M_w\) and \(M_w / M_n\) were confirmed by GPC (solvent: THF, standard: polystyrene).

[0576] [Chemical formula 161]

[0577]

[0578] [Examples 1 - 19, Comparative Examples 1, 2] Preparation and Evaluation of Resist Materials

[0579] (1) Preparation of Resist Materials

[0580] The solution obtained by dissolving each component with the composition shown in Table 1 was filtered through a 0.2 - μm filter to prepare the resist material. The resist materials of Examples 1 - 18 and Comparative Example 1 were positive type, and the resist materials of Example 19 and Comparative Example 2 were negative type.

[0581] In Table 1, each component is as described below.

[0582] · Organic solvent: PGMEA (propylene glycol monomethyl ether acetate)

[0583] DAA (diacetone alcohol)

[0584] EL (ethyl lactate)

[0585] · Acid generator: PAG - 1, PAG - 2

[0586] [Chemical formula 162]

[0587]

[0588] · Comparative quencher: cQ - 1

[0589] [Chemical formula 163]

[0590]

[0591] (2) EUV Lithography Evaluation

[0592] Each of the resist materials shown in Table 1 was spin-coated on a Si substrate on which a silicon-containing spin-on hard mask SHB-A940 (silicon content: 43% by mass) manufactured by Shin-Etsu Chemical Co., Ltd. was formed with a film thickness of 20 nm, and prebaked at 100 °C for 60 seconds using a hot plate to obtain a resist film with a film thickness of 60 nm. Then, the aforementioned resist film was exposed using an EUV scanning exposure machine NXE3400 (NA 0.33, σ 0.9 / 0.6, quadrupole illumination, mask for a hole pattern with a pitch of 44 nm and a +20% offset on the wafer) manufactured by ASML, PEB was performed at the temperature described in Table 1 for 60 seconds on a hot plate, and development was performed for 30 seconds using a 2.38 mass% TMAH aqueous solution. A hole pattern with a size of 22 nm was obtained in Examples 1 to 18 and Comparative Example 1, and a dot pattern with a size of 22 nm was obtained in Example 19 and Comparative Example 2.

[0593] Using a length-measuring SEM (CG6300) manufactured by Hitachi High-Tech Corporation, the exposure dose when the hole or dot size was formed to 22 nm was measured and defined as the sensitivity. Also, the sizes of 50 holes or dots at this time were measured, and three times the standard deviation (σ) obtained from the results (3σ) was determined as the CDU. The results are collectively shown in Table 1.

[0594] [Table 1]

[0595]

[0596]

[0597] From the results shown in Table 1, it can be seen that the resist material of the present invention containing a sulfonium salt of an iodinated phenol compound has high sensitivity and an improved CDU.

Claims

1. A resist material comprising: a sulfonium salt of an iodinated phenol compound.

2. The resist material according to claim 1, wherein The sulfonium salt is represented by the following formula (1): Wherein, m is 1, 2, 3, 4 or 5; n is 0, 1, 2, 3 or 4; however, 1≤m+n≤5; R 1 are each independently a halogen atom other than an iodine atom, a hydroxyl group, a nitro group, a cyano group, a hydrocarbon group having 1 to 20 carbon atoms, a hydrocarbon oxy group having 1 to 20 carbon atoms, a hydrocarbon carbonyl oxy group having 2 to 20 carbon atoms, or a hydrocarbon sulfonyloxy group having 1 to 20 carbon atoms, and the hydrocarbon group, the hydrocarbon oxy group, the hydrocarbon carbonyl oxy group, and the hydrocarbon sulfonyloxy group may have at least one selected from a halogen atom, an oxygen atom, a sulfur atom, and a nitrogen atom; R 2 ~R 4 are independently a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom; and R 2 and R 3 They may also bond to each other and to the sulfur atom to which they are bonded to form a ring. The resist material according to claim 1 , further comprising a base polymer.

4. The resist material according to claim 3, wherein The base polymer contains at least one selected from the group consisting of a repeating unit represented by the following formula (a1) and a repeating unit represented by the following formula (a2); In the formula, R A are each independently a hydrogen atom or a methyl group; X 1 is a single bond, a phenylene group or a naphthylene group, or a linking group having 1 to 12 carbon atoms and containing at least one selected from an ester bond, an ether bond, and a lactone ring, and the phenylene group, the naphthylene group, and the linking group may also have at least one selected from a halogen atom, a hydroxyl group, a saturated hydrocarbon oxy group having 1 to 8 carbon atoms, and a saturated hydrocarbon carbonyloxy group having 2 to 8 carbon atoms; X 2 is a single bond, an ester bond or an amide bond; X 3 is a single bond, an ether bond or an ester bond; R 11 and R 12 are each independently an acid-labile group; R 13 is a hydroxyl group, a halogen atom, a trifluoromethyl group, a cyano group, or a saturated hydrocarbon group having 1 to 6 carbon atoms; R 14 It is a single bond or an alkanediyl group having 1 to 6 carbon atoms, and a portion of the -CH2- of the alkanediyl group may be 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. The resist material according to claim 4 , which is a chemically amplified positive resist material.

6. The resist material according to claim 3, wherein The base polymer does not contain acid-labile groups. The resist material according to claim 6 , which is a chemically amplified negative resist material.

8. The resist material according to claim 3, wherein The base polymer contains at least one selected from the group consisting of a repeating unit represented by the following formula (f1), a repeating unit represented by the following formula (f2), a repeating unit represented by the following formula (f3), a repeating unit represented by the following formula (f4), and a repeating unit represented by the following formula (f5); In the formula, R A are each independently a hydrogen atom or a methyl group; Z 1 is a single bond, an aliphatic alkylene 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 these groups, or -OZ 11 -、-C(=O)-OZ 11 -or-C(=O)-NH-Z 11 -;Z 11 It is an aliphatic alkylene 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, and may also contain a carbonyl group, an ester bond, an ether bond, or a hydroxyl group; Z 2 is a single bond or an ester bond; Z 3 is a single bond, -Z 31 -C(=O)-O-, -Z 31 -O- or -Z 31 -OC(=O)-; Z 31 An aliphatic alkylene group having 1 to 12 carbon atoms, a phenylene group, or a group having 7 to 18 carbon atoms obtained by combining these groups, and may also contain a carbonyl group, an ester bond, an ether bond, an iodine atom, or a bromine atom; Z 4 is methylene, 2,2,2-trifluoro-1,1-ethanediyl or carbonyl; Z 5 is a 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 having 1 to 6 carbon atoms, a phenylene group, a fluorinated phenylene group or a phenylene group substituted with a trifluoromethyl group, and may also contain a carbonyl group, an ester bond, an ether bond, a halogen atom or a hydroxyl group; Z 6 is a single bond, a phenylene ring, a naphthylene ring, an ester bond, or an amide bond; Z 7A is a single bond or a divalent organic group having 1 to 24 carbon atoms, and may have at least one selected from a halogen atom, an oxygen atom, a nitrogen atom, and a sulfur atom; Z 7B It is a monovalent organic group having 1 to 10 carbon atoms, and may have at least one selected from a halogen atom, an oxygen atom, a nitrogen atom, and a sulfur atom; Z 8 It is a single bond, an ether bond, an ester bond, a thioether bond or an alkanediyl group having 1 to 6 carbon atoms; Z 9 A trivalent organic group having 1 to 12 carbon atoms, and may have at least one selected from an oxygen atom, a nitrogen atom and a sulfur atom; R 21 ~R 25 are independently a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms which may contain a hetero atom; and R 23 and R 24 They can also bond to each other and to the sulfur atoms to which they are bonded to form a ring; R 26 are each independently a saturated hydrocarbon group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a fluorine atom, an iodine atom, a trifluoromethoxy group, a difluoromethoxy group, a cyano group or a nitro group; R is a (j+2)-valent aromatic hydrocarbon group having 6 to 10 carbon atoms; j are each independently an integer from 0 to 5; M - It is a non-nucleophilic relative ion.

9. The resist material according to claim 1, further comprising an acid generator that generates a strong acid.

10. The resist material according to claim 9, wherein The acid generator is one that generates sulfonic acid, imidic acid or methylated acid. The resist material according to claim 1 , further comprising an organic solvent.

12. The resist material according to claim 1, further comprising a surfactant.

13. A pattern forming method comprising the following steps: forming a resist film on a substrate using the resist material according to any one of claims 1 to 12, exposing the resist film to high energy radiation, and The exposed resist film is developed using a developer.

14. The pattern forming method according to claim 13, wherein: The high-energy ray is KrF excimer laser, ArF excimer laser, electron beam or extreme ultraviolet ray with a wavelength of 3 to 15 nm.

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