Positive resist material and pattern forming method

Abstract

The invention relates to a positive resist material and a pattern forming method. The invention provides a positive resist material which has higher sensitivity, high resolution, small LWR, good CDU and good pattern shape after exposure compared with a known positive resist material, and a pattern forming method. A positive resist material includes a base polymer including a repeating unit a represented by formula (a). # imgabs0 #

Description

Technical Field

[0001] The present invention relates to a positive 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. Because 5G high-speed communication and artificial intelligence (AI) are becoming more and more popular, high-performance devices for processing them are required. As the most advanced miniaturization technology, mass production of devices at 5 nm nodes and 3 nm nodes using extreme ultraviolet (EUV) lithography with a wavelength of 13.5 nm has been carried out. Furthermore, for next-generation 2 nm node devices and the next-next-generation 14 Å nodes, the use of EUV lithography has also been explored, and IMEC in Belgium has announced the development of 2 Å devices.

[0003] With the progress of miniaturization, blurring of images due to acid diffusion has become a problem. In order to ensure the resolution of fine patterns with a processing size of 45 nm or less, it has been proposed that not only the improvement of the dissolution contrast proposed in the past, 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 reduce acid diffusion to the limit, the sensitivity and contrast will decrease significantly.

[0004] Sensitivity, resolution, and line width roughness (LWR) show a trade-off relationship. In order to improve the resolution, acid diffusion needs to be suppressed, but if the acid diffusion distance is shortened, the sensitivity will decrease.

[0005] An acid generator that generates an acid having steric hindrance is effective for suppressing acid diffusion. A scheme has been proposed in which a polymer contains a repeating unit derived from an onium salt having a polymerizable unsaturated bond. At this time, the polymer also acts as an acid generator (polymer-bound acid generator). Patent Document 1 proposes a scheme of a sulfonium salt and a iodonium salt having a polymerizable unsaturated bond that generates a specific sulfonic acid. Patent Document 2 proposes a scheme of a sulfonium salt in which a sulfonic acid is directly bonded to the main chain.

[0006] A resist material containing a polymer-bound acid generator having an onium salt structure in which an anion having an iodine atom is bonded to the main chain has been proposed (Patent Document 3). By having an iodine atom with a large absorption of EUV, the efficiency of decomposition of the acid generator during exposure is increased, and the sensitivity is increased. The amount of photon absorption increases, and the physical contrast can be improved.

[0007] A resist material containing a polymer in which the carboxyl group of vinyl salicylic acid is replaced with an acid-labile group has been proposed (Patent Document 4). In addition, a resist material using a polymer in which both the carboxyl group and the phenolic hydroxyl group of vinyl salicylic acid are replaced with a cyclic acetal has been proposed (Patent Document 5).

[0008] Prior art documents

[0009] Patent documents

[0010] [Patent Document 1] Japanese Patent Laid-Open No. 2006-045311

[0011] [Patent Document 2] Japanese Patent Laid-Open No. 2006-178317

[0012] [Patent Document 3] Japanese Patent Laid-Open No. 2018-197853

[0013] [Patent Document 4] Japanese Patent Laid-Open No. 2022-066864

[0014] [Patent Document 5] International Publication No. 2023 / 162837

[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] It is desired to develop a positive resist material that has higher sensitivity than known positive resist materials and can improve the LWR of line patterns and the dimensional uniformity (CDU) of hole patterns.

[0019] In view of the above circumstances, an object of the present invention is to provide a positive resist material that has higher sensitivity, higher resolution, smaller LWR, good CDU, and a good pattern shape after exposure, and a pattern forming method.

[0020] [Means for solving the problems]

[0021] The inventors of the present application have made diligent investigations in order to obtain a positive resist material with high resolution, small LWR, and good CDU, which has been expected in recent years. As a result, it has been necessary to improve the development contrast and suppress swelling in the developer. The resist material containing a polymer in which only the carboxyl group of vinyl salicylic acid is substituted with an acid-labile group as described in Patent Document 4 has a problem of low dissolution contrast because the phenolic hydroxyl group is not substituted. The resist material containing a polymer in which both the carboxyl group and the phenolic hydroxyl group of vinyl salicylic acid are substituted with acid-labile groups having a cyclic acetal structure as described in Patent Document 5 has an improved dissolution contrast but is still not satisfactory. The inventors of the present application have found that a resist material containing a polymer having a structure in which both the carboxyl group and the phenolic hydroxyl group of an aromatic hydroxy acid such as vinyl salicylic acid are substituted with acid-labile groups having a cyclic acetal structure containing an aromatic group can sufficiently suppress the alkali solubility of the unexposed portion, and the exposed portion can improve the dissolution contrast in a state where swelling is suppressed, and the etching resistance can be improved by the introduction of an aromatic group, and it is effective as a base polymer of a positive resist material with good LWR and CDU.

[0022] Furthermore, it has been found that in order to improve the dissolution contrast, a repeating unit in which a hydrogen atom of a carboxyl group or a phenolic hydroxyl group is substituted with an acid-labile group is introduced, and it can be highly sensitive and the contrast of the alkali dissolution rate before and after exposure is greatly improved, it is highly sensitive and has a high effect of suppressing acid diffusion, has high resolution, the pattern shape after exposure is good, small LWR, and good CDU, and a positive resist material ideal particularly as a fine pattern forming material for manufacturing ultra-LSI or photomasks can be obtained, and thus the present invention has been completed.

[0023] That is, the present invention provides the following positive resist materials and pattern forming methods.

[0024] 1. A positive resist material comprising a base polymer containing a repeating unit a represented by the following formula (a),

[0025] [Chemical formula 1]

[0026]

[0027] In the formula, m is 0 or 1. n is an integer from 0 to 4.

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

[0029] X 1 is a single bond or an ester bond.

[0030] X 2 is a single bond, a saturated alkylene group having 1 to 10 carbon atoms, a phenylene group or a naphthylene group.

[0031] X 3 is a single bond, an ester bond, an ether bond or a carbonyl group.

[0032] R 1 is a hydrocarbon group having 1 to 8 carbon atoms, a hydroxyl group, a hydrocarbon oxy group having 1 to 8 carbon atoms, a hydrocarbon carbonyloxy group having 2 to 8 carbon atoms, a hydrocarbon oxycarbonyloxy group having 2 to 8 carbon atoms, or a halogen atom.

[0033] R 2 and R 3 are each independently a single bond, a methylene group, an ethylene group, a propylene group, or a butylene group, and may be substituted with a halogen atom. However, R 2 and R 3 are not simultaneously a single bond.

[0034] Ring R is a benzene ring or a naphthalene ring, and may also be substituted with a hydrocarbon group having 1 to 8 carbon atoms, a hydroxyl group, a hydrocarbon oxy group having 1 to 8 carbon atoms, a hydrocarbon carbonyloxy group having 2 to 8 carbon atoms, a hydrocarbon oxycarbonyloxy group having 2 to 8 carbon atoms, or a halogen atom.

[0035] *1 and *2 represent the atomic bonds of the carbon atoms on the aromatic ring in the sum formula.

[0036] 2. The positive resist material according to 1., wherein the base polymer further contains a repeating unit b in which a hydrogen atom of a carboxyl group or a phenolic hydroxyl group is substituted with an acid-labile group.

[0037] 3. The positive resist material according to 2., wherein the repeating unit b is at least one selected from the repeating unit b1 represented by the following formula (b1) and the repeating unit b2 represented by the following formula (b2).

[0038] [Chemical formula 2]

[0039]

[0040] In the formula, R A are each independently a hydrogen atom or a methyl group.

[0041] Y 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 nitro group, a hydroxyl group, a saturated hydrocarbon oxy group having 1 to 8 carbon atoms, a saturated hydrocarbon carbonyloxy group having 2 to 8 carbon atoms, and a saturated hydrocarbon oxycarbonyloxy group having 2 to 8 carbon atoms.

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

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

[0044] R 11 and R 12 are acid-labile groups.

[0045] R 13 is a fluorine atom, a trifluoromethyl group, a cyano group, or an alkyl group having 1 to 6 carbon atoms.

[0046] R 14 is a single bond or an alkanediyl group having 1 to 6 carbon atoms, and a part of the -CH 2 - of this alkanediyl group may also be substituted with an ether bond or an ester bond.

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

[0048] 4. The positive resist material according to any one of 1. to 3., wherein the base polymer further contains a repeating unit c having an adhesion group selected from a hydroxyl group, a carboxyl group, a lactone ring, a carbonate group, a thiocarbonate group, a carbonyl group, a cyclic acetal group, an ether bond, an ester bond, a sulfonate bond, a cyano group, an amide group, -O-C(=O)-S-, and -O-C(=O)-NH-.

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

[0050] 6. The positive resist material according to any one of 1. to 5., further containing an acid generator.

[0051] 7. The positive resist material according to any one of 1. to 6., further containing a quencher.

[0052] 8. The positive resist material according to any one of 1. to 7., further containing a surfactant.

[0053] 9. A pattern forming method, comprising the following steps:

[0054] forming a resist film on a substrate using the positive resist material according to any one of 1. to 8.,

[0055] exposing the resist film to high-energy radiation, and

[0056] developing the exposed resist film using a developer.

[0057] 10. The pattern forming method according to 9., wherein the high-energy radiation is i-ray, KrF excimer laser, ArF excimer laser, electron beam, or extreme ultraviolet ray having a wavelength of 3 to 15 nm.

[0058] [Effects of the Invention]

[0059] The positive resist material of the present invention is based on a polymer having a structure in which the carboxyl group and hydroxyl group of an aromatic hydroxy acid such as salicylic acid are replaced with acid-labile groups having a cyclic acetal structure containing an aromatic group. By using the acid generated by exposure to deprotect the acid-labile group, a polymer having the structure of an aromatic hydroxy acid such as salicylic acid is formed. It not only has high alkali solubility in the exposed part, but also has low swelling and good properties, and has a high effect of suppressing acid diffusion. Moreover, it has high sensitivity, high resolution, good pattern shape after exposure, small LWR, excellent CDU, no tailing or residue in the non-spacing part, and no micro-bridging of pattern connection. Aromatic hydroxy acids such as salicylic acid, the carboxyl group and phenolic hydroxyl group will form a hydrogen-bonded ring, and have the effect of reducing the swelling of the carboxyl group in the alkali developer. The polymer having the structure of an aromatic hydroxy acid such as salicylic acid substituted with an acid-labile group has low swelling and an increased alkali dissolution rate, so the aforementioned good properties can be obtained. Therefore, having these excellent properties, it has extremely high practicality, and is very useful especially as a fine pattern forming material for ultra-LSI manufacturing or photomasks using EB drawing, and a pattern forming material for EB or EUV exposure. The positive resist material of the present invention can be applied not only to, for example, lithography for semiconductor circuit formation, but also to the formation of mask circuit patterns, micro machines, and thin film head circuit formation. Detailed Embodiments

[0060] [Positive Resist Material]

[0061] The positive resist material of the present invention contains a base polymer having a structure in which both the carboxyl group and phenolic hydroxyl group of an aromatic hydroxy acid are replaced with acid-labile groups having a cyclic acetal structure containing an aromatic group.

[0062] [Base Polymer]

[0063] Preferably, the aforementioned base polymer contains a repeating unit a represented by the following formula (a).

[0064] [Chemical Formula 3]

[0065]

[0066] In formula (a), m is 0 or 1. n is an integer from 0 to 4.

[0067] In formula (a), R A is a hydrogen atom or a methyl group.

[0068] In formula (a), X 1 is a single bond or an ester bond.

[0069] In formula (a), X 2is a single bond, a saturated alkylene group having 1 to 10 carbon atoms, a phenylene group or a naphthylene group. The aforementioned saturated alkylene group can be linear, branched or cyclic. Specific examples thereof include alkanediyl groups having 1 to 10 carbon atoms such as methane diyl, 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; and cycloaliphatic saturated alkylene groups having 3 to 10 carbon atoms such as cyclopentane diyl, cyclohexane diyl, norbornane diyl, adamantane diyl.

[0070] In formula (a), X 3 is a single bond, an ester bond, an ether bond or a carbonyl group.

[0071] In formula (a), R 1 is a hydrocarbon group having 1 to 8 carbon atoms, a hydroxyl group, a hydrocarbon oxy group having 1 to 8 carbon atoms, a hydrocarbon carbonyl oxy group having 2 to 8 carbon atoms, a hydrocarbon oxycarbonyl oxy group having 2 to 8 carbon atoms or a halogen atom. The hydrocarbon moieties of the aforementioned hydrocarbon group, hydrocarbon oxy group, hydrocarbon carbonyl oxy group and hydrocarbon oxycarbonyl oxy group can be saturated or unsaturated, and can be linear, branched or cyclic. Specific examples thereof include alkyl groups having 1 to 8 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; cycloaliphatic saturated hydrocarbon groups having 3 to 8 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 8 carbon atoms such as vinyl, 1-propenyl, 2-propenyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl; alkynyl groups having 2 to 8 carbon atoms such as ethynyl, propynyl, butynyl, pentynyl, hexynyl, heptynyl, octynyl; cycloaliphatic unsaturated aliphatic hydrocarbon groups having 3 to 8 carbon atoms such as cyclopentenyl, cyclohexenyl, methylcyclopentenyl, methylcyclohexenyl, ethylcyclopentenyl, ethylcyclohexenyl, norbornenyl; groups obtained by combining them, etc.

[0072] In formula (a), R 2 and R 3 are each independently a single bond, a methylene group, an ethylene group, a propylene group or a butylene group, and may be substituted with a halogen atom. However, R 2 and R 3 are not both single bonds at the same time.

[0073] In formula (a), ring R is a benzene ring or a naphthalene ring, which may also be substituted by a hydrocarbon group having 1 to 8 carbon atoms, a hydroxyl group, a hydrocarbon oxy group having 1 to 8 carbon atoms, a hydrocarbon carbonyloxy group having 2 to 8 carbon atoms, a hydrocarbon oxycarbonyloxy group having 2 to 8 carbon atoms, or a halogen atom. The hydrocarbon group of the aforementioned hydrocarbon group, hydrocarbon oxy group, hydrocarbon carbonyloxy group, and hydrocarbon oxycarbonyloxy group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof are the same as the examples exemplified for the hydrocarbon group represented by R 1 The exemplified hydrocarbon groups are the same examples.

[0074] In formula (a), *1 and *2 represent atomic bonds to carbon atoms on the aromatic ring in the formula. The bonding positions of *1 and *2 are not particularly limited, and it is preferable that they bond to adjacent carbon atoms on the aromatic ring.

[0075] Specific examples of the monomer that gives repeating unit a are listed below, but are not limited thereto. Also, in the following formula, R A is as described above.

[0076] [Chemical formula 4]

[0077]

[0078] [Chemical formula 5]

[0079]

[0080] [Chemical formula 6]

[0081]

[0082] [Chemical formula 7]

[0083]

[0084] [Chemical formula 8]

[0085]

[0086] [Chemical formula 9]

[0087]

[0088] [Chemical formula 10]

[0089]

[0090] [Chemical formula 11]

[0091]

[0092] [Chemical formula 12]

[0093]

[0094] [Chemical formula 13]

[0095]

[0096] [Chemical Formula 14]

[0097]

[0098] [Chemical Formula 15]

[0099]

[0100] [Chemical Formula 16]

[0101]

[0102] [Chemical Formula 17]

[0103]

[0104] The synthesis method of the aforementioned monomer, for example, a method of subjecting an aromatic hydroxy acid compound and an indanone compound to a cyclization reaction under an acid catalyst. If the aromatic hydroxy acid compound is substituted with a bromine atom or a hydroxyl group, a polymerizable double bond can be introduced by carrying out vinylation or methacryloylation after the cyclization reaction.

[0105] The aforementioned base polymer may further contain a repeating unit b in which a hydrogen atom of a carboxyl group or a phenolic hydroxyl group is substituted with an acid-labile group. The repeating unit b is for making the dissolution contrast higher.

[0106] The repeating unit b preferably contains at least one selected from the repeating unit b1 represented by the following formula (b1) and the repeating unit b2 represented by (b2).

[0107] [Chemical Formula 18]

[0108]

[0109] In formulas (b1) and (b2), R A are each independently a hydrogen atom or a methyl group.

[0110] Y 1 is a single bond, a phenylene group or 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 nitro group, a hydroxyl group, a saturated hydrocarbon oxy group having 1 to 8 carbon atoms, a saturated hydrocarbon carbonyloxy group having 2 to 8 carbon atoms, and a saturated hydrocarbon oxycarbonyloxy group having 2 to 8 carbon atoms. Y 2 is a single bond, an ester bond or an amide bond. Y 3 is a single bond, an ether bond or an ester bond. R 11 and R 12 are acid-labile groups. R 13is a fluorine atom, a trifluoromethyl group, a cyano group, or an alkyl 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 the -CH 2 - 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.

[0111] Examples of the monomer providing the repeating unit b1 are as follows, but are not limited to these. Also, in the following formula, R A and R 11 are as described above.

[0112] [Chemical formula 19]

[0113]

[0114] [Chemical formula 20]

[0115]

[0116] [Chemical formula 21]

[0117]

[0118] Examples of the monomer providing the repeating unit b2 are as follows, but are not limited to these. Also, in the following formula, R A and R 12 are as described above.

[0119] [Chemical formula 22]

[0120]

[0121] R 11 or R 12 There are various choices for the acid-labile group represented, for example: those represented by the following formulae (AL-1) to (AL-3).

[0122] [Chemical formula 23]

[0123]

[0124] In the formula, the dashed line is an atomic bond.

[0125] In formula (AL-1), c is an integer of 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 hydrocarbyl 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). Also, the tertiary hydrocarbon group means a group obtained by detaching a hydrogen atom from a tertiary carbon atom of a hydrocarbon.

[0126] R L1The represented tertiary hydrocarbon group can be saturated or unsaturated, and can be branched or cyclic. Specific examples thereof include a tert-butyl group, a tert-pentyl group, a 1,1-diethylpropyl group, a 1-ethylcyclopentyl group, a 1-butylcyclopentyl group, a 1-ethylcyclohexyl group, a 1-butylcyclohexyl group, a 1-ethyl-2-cyclopentenyl group, a 1-ethyl-2-cyclohexenyl group, a 2-methyl-2-adamantyl group, and the like. The aforementioned trihydrocarbylsilyl group, such as a trimethylsilyl group, a triethylsilyl group, a dimethyl-tert-butylsilyl group, and the like. The aforementioned saturated hydrocarbon group containing a carbonyl group, an ether bond or an ester bond can be linear, branched or cyclic, but a cyclic one is preferred. Specific examples thereof include a 3-oxocyclohexyl group, a 4-methyl-2-oxooxan-4-yl group, a 5-methyl-2-oxotetrahydrofuran-5-yl group, a 2-tetrahydropyranyl group, a 2-tetrahydrofuranyl group, and the like.

[0127] The acid-labile group represented by the formula (AL-1), such as a tert-butoxycarbonyl group, a tert-butoxycarbonylmethyl group, a tert-pentyloxycarbonyl group, a tert-pentyloxycarbonylmethyl group, a 1,1-diethylpropoxycarbonyl group, a 1,1-diethylpropoxycarbonylmethyl group, a 1-ethylcyclopentyloxycarbonyl group, a 1-ethylcyclopentyloxycarbonylmethyl group, a 1-ethyl-2-cyclopentenoxycarbonyl group, a 1-ethyl-2-cyclopentenoxycarbonylmethyl group, a 1-ethoxyethoxycarbonylmethyl group, a 2-tetrahydropyranyloxycarbonylmethyl group, a 2-tetrahydrofuryloxycarbonylmethyl group, and the like.

[0128] Further, the acid-labile group represented by the formula (AL-1) may also include the groups represented by the following formulas (AL-1)-1 to (AL-1)-10.

[0129] [Chemical formula 24]

[0130]

[0131] In the formula, the dashed line is an atomic bond.

[0132] In the formulas (AL-1)-1 to (AL-1)-10, c is as described above. R L8 Each independently represents a saturated hydrocarbon group having 1 to 10 carbon atoms or an aryl group having 6 to 20 carbon atoms. R L9 represents a hydrogen atom or a saturated hydrocarbon group having 1 to 10 carbon atoms. R L10 represents 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 can be linear, branched or cyclic.

[0133] In the formula (AL-2), R L2 and R L3Each independently represents 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 a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a cyclopentyl group, a cyclohexyl group, a 2-ethylhexyl group, a n-octyl group, and the like.

[0134] In formula (AL-2), R L4 represents 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. The aforementioned hydrocarbon group, for example, includes a saturated hydrocarbon group having 1 to 18 carbon atoms, etc., and a part of these hydrogen atoms may also be substituted with a hydroxyl group, an alkoxy group, an oxo group, an amino group, an alkylamino group, or the like. Such a substituted saturated hydrocarbon group, for example, includes those shown below.

[0135] [Chemical formula 25]

[0136]

[0137] In the formula, the dashed line represents an atomic bond.

[0138] 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, or together with the carbon atoms and oxygen atoms, form a ring. In this case, R L2 and R L3 , R L2 and R L4 , or R L3 and R L4 each 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 these bonds is preferably 3 to 10, more preferably 4 to 10.

[0139] Among the acid-labile groups represented by formula (AL-2), linear or branched ones may include those represented by the following formulas (AL-2)-1 to (AL-2)-69, but are not limited thereto. Also, in the following formulas, the dashed line represents an atomic bond.

[0140] [Chemical formula 26]

[0141]

[0142] [Chemical formula 27]

[0143]

[0144] [Chemical formula 28]

[0145]

[0146] [Chemical formula 29]

[0147]

[0148] Among the acid-labile groups represented by formula (AL-2), cyclic ones include tetrahydrofuran-2-yl, 2-methyltetrahydrofuran-2-yl, tetrahydropyran-2-yl, 2-methyltetrahydropyran-2-yl, and the like.

[0149] Furthermore, the acid-labile group is, for example, a group represented by the following formula (AL-2a) or (AL-2b). The base polymer can also be intermolecularly or intramolecularly crosslinked using the aforementioned acid-labile group.

[0150] [Chemical formula 30]

[0151]

[0152] In the formula, the dashed line is an atomic bond.

[0153] 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 can be linear, branched, or cyclic. Also, R L11 and R L12 can also be bonded to each other and form a ring together with the carbon atom to which they are bonded. 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 subhydrocarbon group having 1 to 10 carbon atoms. The aforementioned saturated subhydrocarbon group can 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.

[0154] 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 - in these groups can be substituted by a heteroatom-containing group, and a part of the hydrogen atoms in these groups can be substituted by a hydroxyl group, a carboxyl group, an acyl group, or a fluorine atom. L A is preferably a saturated subhydrocarbon group having 1 to 20 carbon atoms, a trivalent saturated hydrocarbon group, a tetravalent saturated hydrocarbon group, etc., a subarylene group having 6 to 30 carbon atoms, etc. The aforementioned saturated hydrocarbon group can be linear, branched, or cyclic. L B-C(=O)-O-, -NH-C(=O)-O- or -NH-C(=O)-NH-.

[0155] The crosslinked acetal group represented by formula (AL-2a) or (AL-2b), such as the groups represented by the following formula (AL-2)-70 to (AL-2)-77, etc.

[0156] [Chemical 31]

[0157]

[0158] In the formula, the dashed line is an atomic bond.

[0159] In formula (AL-3), R L5 , R L6 and R L7 are each 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 cycloaliphatic saturated hydrocarbon group having 3 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, a cycloaliphatic 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.

[0160] The group represented by formula (AL-3), such as 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.

[0161] Also, the group represented by formula (AL-3) may also include the groups represented by the following formula (AL-3)-1 to (AL-3)-19.

[0162] [Chemical 32]

[0163]

[0164] In the formula, the dashed line is an atomic bond.

[0165] In formula (AL-3)-1 to (AL-3)-19, 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 L17Each is 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 or the like. R F is a fluorine atom or a trifluoromethyl group. g is an integer of 1 to 5.

[0166] Also, examples of the acid-labile group include the groups represented by the following formula (AL-3)-20 or (AL-3)-21. The aforementioned acid-labile group can also be used to crosslink the polymer intramolecularly or intermolecularly.

[0167] [Chemical formula 33]

[0168]

[0169] In the formula, the dashed line represents an atomic bond.

[0170] In formula (AL-3)-20 and (AL-3)-21, R L14 is as described above. R L18 is an (h + 1)-valent saturated hydrocarbon group having 1 to 20 carbon atoms or an (h + 1)-valent arylene group having 6 to 20 carbon atoms, and may contain heteroatoms such as an oxygen atom, a sulfur atom, and a nitrogen atom. The aforementioned saturated hydrocarbon group may be linear, branched, or cyclic. h is an integer of 1 to 3.

[0171] The aforementioned base polymer may further contain a repeating unit c having a cohesive group selected from a hydroxyl group, a carboxyl group, a lactone ring, a carbonate group, a thiocarbonate group, a carbonyl group, a cyclic acetal group, an ether bond, an ester bond, a sulfonate bond, a cyano group, an amide group, -O-C(=O)-S-, and -O-C(=O)-NH-.

[0172] Examples of the monomer that gives the repeating unit c are as follows, but are not limited to these. Also, in the following formula, R A is as described above.

[0173] [Chemical formula 34]

[0174]

[0175] [Chemical formula 35]

[0176]

[0177] [Chemical formula 36]

[0178]

[0179] [Chemical formula 37]

[0180]

[0181] [Chemical formula 38]

[0182]

[0183] [Chemical formula 39]

[0184]

[0185] [Chemical formula 40]

[0186]

[0187] [Chemical formula 41]

[0188]

[0189] [Chemical formula 42]

[0190]

[0191] [Chemical formula 43]

[0192]

[0193] [Chemical formula 44]

[0194]

[0195] [Chemical formula 45]

[0196]

[0197] [Chemical formula 46]

[0198]

[0199] The aforementioned base polymer may also contain a repeating unit d that acts as an acid generator. The repeating unit d preferably contains at least one selected from the repeating unit represented by the following formula (d1) (hereinafter also referred to as repeating unit d1), the repeating unit represented by the following formula (d2) (hereinafter also referred to as repeating unit d2), the repeating unit represented by the following formula (d3) (hereinafter also referred to as repeating unit d3), the repeating unit represented by the following formula (d4) (hereinafter also referred to as repeating unit d4), and the repeating unit represented by the following formula (d5) (hereinafter also referred to as repeating unit d5).

[0200] [Chemical formula 47]

[0201]

[0202] In formulas (d1) to (d3), R A is independently a hydrogen atom or a methyl group.

[0203] In formula (d1), Z 1A group having 7 to 18 carbon atoms obtained from a single bond, an aliphatic alkylene group having 1 to 6 carbon atoms, a phenylene group, a naphthylene group, or a combination thereof, 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 from a combination thereof, and may also contain a carbonyl group, an ester bond, an ether bond, or a hydroxyl group.

[0204] In formula (d1), R 21 and R 22 Are each independently a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms that may also contain a heteroatom. The aforementioned hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof are the same as the examples of the hydrocarbon group having 1 to 20 carbon atoms represented by R 41 to R 45 described in the explanations of formulas (M1) and (M2) below.

[0205] Examples of the cation of the monomer that gives the repeating unit d1 are as follows, but are not limited to these. Also, in the following formula, R A Is as described above.

[0206] [Chemical formula 48]

[0207]

[0208] In formula (d1), X - Is a non-nucleophilic counter ion. 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, methylide ions such as tris(trifluoromethylsulfonyl)methylide ion and tris(perfluoroethylsulfonyl)methylide ion.

[0209] Examples of the aforementioned non-nucleophilic counter ion further include sulfonate ions substituted with a fluorine atom at the α-position represented by the following formula (d1-1), sulfonate ions substituted with a fluorine atom at the α-position and a trifluoromethyl group at the β-position represented by the following formula (d1-2), etc.

[0210] [Chemical formula 49]

[0211]

[0212] In formula (d1-1), R 31 is a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and the hydrocarbon group may also contain an ether bond, an ester bond, a carbonyl group, a lactone ring or a fluorine atom. The aforementioned hydrocarbon group may be saturated or unsaturated, and may be linear, branched or cyclic.

[0213] In formula (d1-2), R 32 is a hydrogen atom, a hydrocarbon group having 1 to 30 carbon atoms or a hydrocarbon carbonyl group having 2 to 30 carbon atoms, and the hydrocarbon group and the hydrocarbon carbonyl group may also contain an ether bond, an ester bond, a carbonyl group or a lactone ring. The aforementioned hydrocarbon group and hydrocarbon carbonyl group may be saturated or unsaturated, and may be linear, branched or cyclic.

[0214] The aforementioned non-nucleophilic counter ion may also be an anion containing an aromatic ring substituted with a bromine atom or an iodine atom represented by the following formula (d1-3).

[0215] [Chemical formula 50]

[0216]

[0217] In formula (d1-3), 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. It is preferable that q is an integer satisfying 1 ≤ q ≤ 3, and more preferably 2 or 3. It is more preferable that r is an integer satisfying 0 ≤ r ≤ 2.

[0218] In formula (d1-3), X BI is an iodine atom or a bromine atom, and when p and / or q are 2 or more, they may be the same or different from each other.

[0219] In formula (d1-3), L 1 is a single bond, an ether bond or 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.

[0220] In formula (d1-3), 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.

[0221] In formula (d1-3), R 33 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 33A )(R33B )、 -N(R 33C )-C(=O)-R 33D or -N(R 33C )-C(=O)-O-R 33D . R 33A and R 33B are each independently a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms. R 33C is a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms, and may also contain a halogen atom, a hydroxyl group, a saturated hydrocarbon oxy group having 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl group having 2 to 6 carbon atoms, or a saturated hydrocarbon carbonyloxy group having 2 to 6 carbon atoms. R 33D 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 oxy group having 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl group having 2 to 6 carbon atoms, or a saturated hydrocarbon carbonyloxy 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 oxy group, hydrocarbon oxycarbonyl group, hydrocarbon carbonyl group, hydrocarbon carbonyloxy group, and hydrocarbon sulfonyloxy group may be linear, branched, or cyclic. When p and / or r is 2 or more, each R 33 may be the same or different from each other.

[0222] Among these, R 33 is preferably a hydroxyl group, -N(R 33C )-C(=O)-R 33D , -N(R 33C )-C(=O)-O-R 33D , a fluorine atom, a chlorine atom, a bromine atom, a methyl group, a methoxy group, etc.

[0223] In formula (d1-3), Rf 1 to Rf 4 are each independently a hydrogen atom, a fluorine atom, or a trifluoromethyl group, but at least one of these is a fluorine atom or a trifluoromethyl group. Also, Rf 1 and Rf 2 may also combine to form a carbonyl group. In particular, it is preferable that both Rf 3 and Rf 4 are fluorine atoms.

[0224] The anions represented by formula (d1-3) are listed below, but are not limited to these. Also, in the following formula, X BI is as described above.

[0225] [Chemical formula 51]

[0226]

[0227] [Chemical formula 52]

[0228]

[0229] [Chemical Formula 53]

[0230]

[0231] [Chemical Formula 54]

[0232]

[0233] [Chemical Formula 55]

[0234]

[0235] [Chemical Formula 56]

[0236]

[0237] [Chemical Formula 57]

[0238]

[0239] [Chemical Formula 58]

[0240]

[0241] [Chemical Formula 59]

[0242]

[0243] [Chemical Formula 60]

[0244]

[0245] [Chemical Formula 61]

[0246]

[0247] [Chemical Formula 62]

[0248]

[0249] [Chemical Formula 63]

[0250]

[0251] [Chemical Formula 64]

[0252]

[0253] [Chemical Formula 65]

[0254]

[0255] [Chemical Formula 66]

[0256]

[0257] [Chemical Formula 67]

[0258]

[0259] [Chemical Formula 68]

[0260]

[0261] [Chemical Formula 69]

[0262]

[0263] [Chemical Formula 70]

[0264]

[0265] [Chemical Formula 71]

[0266]

[0267] [Chemical Formula 72]

[0268]

[0269] [Chemical Formula 73]

[0270]

[0271] In formula (d2), Z 2 is a single bond or an ester bond. Z 3 is a single bond, -Z 31 -C(=O)-O- or -Z 31 -O-. Z 31 is an 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, a nitro group, a cyano group, an ester bond, an ether bond, a carbamate bond, a fluorine atom, an iodine atom, or a bromine atom. Z 4 is a single bond, a methylene group, or an ethylene group.

[0272] In formula (d2), Rf 1 to Rf 4 are each independently a hydrogen atom, a fluorine atom, or a trifluoromethyl group, but at least one is a fluorine atom or a trifluoromethyl group. Also, Rf 1 and Rf 2 may also combine to form a carbonyl group.

[0273] Anions of the monomer that gives the repeating unit d2 are listed below, but are not limited to these. Also, in the following formula, R A is as described above.

[0274] [Chemical Formula 74]

[0275]

[0276] [Chemical Formula 75]

[0277]

[0278] [Chemical Formula 76]

[0279]

[0280] [Chemical Formula 77]

[0281]

[0282] [Chemical Formula 78]

[0283]

[0284] [Chemical Formula 79]

[0285]

[0286] [Chemical Formula 80]

[0287]

[0288] [Chemical Formula 81]

[0289]

[0290] [Chemical Formula 82]

[0291]

[0292] [Chemical Formula 83]

[0293]

[0294] [Chemical Formula 84]

[0295]

[0296] [Chemical Formula 85]

[0297]

[0298] [Chemical Formula 86]

[0299]

[0300] [Chemical Formula 87]

[0301]

[0302] [Chemical Formula 88]

[0303]

[0304] [Chemical Formula 89]

[0305]

[0306] In formula (d3), Z 5 is a single bond, methylene, ethylene, phenylene, methylphenylene, dimethylphenylene, fluorophenylene, phenyl substituted with trifluoromethyl, -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, phenylene, methylphenylene, dimethylphenylene, fluorophenylene or phenyl substituted with trifluoromethyl, and may also contain a carbonyl group, an ester bond, an ether bond, a hydroxyl group or a halogen atom.

[0307] Anions of the monomer that gives repeating unit d3 are listed below, but are not limited to these. Also, in the following formula, R A is as described above.

[0308] [Chemical Formula 90]

[0309]

[0310] [Chemical Formula 91]

[0311]

[0312] In formulas (d4) and (d5), R A are each independently a hydrogen atom or a methyl group. R B are each independently a hydrogen atom, or may also bond with Z 6 to form a ring.

[0313] In formulas (d4) and (d5), Z 6 is a single bond, phenylene, naphthylene ring, ester bond or amide bond.

[0314] In formula (d4), Z 7A is a single bond or a divalent organic group having 1 to 24 carbon atoms, and may also have at least 1 selected from a halogen atom, an oxygen atom, a nitrogen atom and a sulfur atom.

[0315] Z 7AThe divalent organic group represented can be saturated or unsaturated, and can be linear, branched or cyclic. Specific examples thereof include hydrocarbon groups having 1 to 24 carbon atoms in which part or all of the hydrogen atoms are substituted with iodine atoms or bromine atoms. The hydrocarbon groups having 1 to 24 carbon atoms include, for example, 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, eicosane-1,20-diyl and other alkanediyls; cyclopentanediyl, methylcyclopentanediyl, dimethylcyclopentanediyl, trimethylcyclopentanediyl, tetramethylcyclopentanediyl, cyclohexanediyl, methylcyclohexanediyl, dimethylcyclohexanediyl, trimethylcyclohexanediyl, tetramethylcyclohexanediyl, norbornanediyl, adamantanediyl and other cycloaliphatic saturated hydrocarbon groups; phenylene, methylphenylene, ethylphenylene, n-propylphenylene, isopropylphenylene, n-butylphenylene, isobutylphenylene, sec-butylphenylene, tert-butylphenylene, naphthylene, methylnaphthylene, ethylnaphthylene, n-propylnaphthylene, isopropylnaphthylene, n-butylnaphthylene, isobutylnaphthylene, sec-butylnaphthylene, tert-butylnaphthylene, biphenyldiyl, methylbiphenyldiyl, dimethylbiphenyldiyl and other arylene groups; groups obtained by combining them, etc. Further, 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 can also contain a hydroxyl group, an ester bond, an ether bond, an amide bond, a urethane bond, a urea bond, etc.

[0316] In formula (d5), 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.

[0317] Z 7BThe monovalent organic group represented may be saturated or unsaturated, and may be linear, branched or cyclic. Specific examples thereof include hydrocarbon groups having 1 to 10 carbon atoms in which part or all of the hydrogen atoms are substituted with iodine atoms or bromine atoms. The hydrocarbon groups having 1 to 10 carbon atoms include, for example, 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; cycloaliphatic 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; cycloaliphatic 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, methylphenyl, 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. Further, Z 7B 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 7B -CH 2 - part 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.

[0318] In formulas (d4) and (d5), Z 8 is a single bond, an ether bond, an ester bond, a thioether bond or an alkanediyl having 1 to 6 carbon atoms.

[0319] In formula (d5), 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 9 The trivalent organic group represented may be saturated or unsaturated, and may be linear, branched or cyclic. Specific examples thereof include groups obtained by removing one hydrogen atom from a C1-C12 subhydrocarbon group. The C1-C12 subhydrocarbon group is, for example, that having 1 to 12 carbon atoms among the C1-C24 subhydrocarbon groups described above. Further, Z9 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 -CH 2 - of 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 also contain a hydroxyl group, an ester bond, an ether bond, an amide bond, a urethane bond, a urea bond, etc.

[0320] In formulas (d4) and (d5), R 23 is 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.

[0321] In formulas (d4) and (d5), the circular R is a (j + 2)-valent aromatic hydrocarbon group having 6 to 10 carbon atoms. Specific examples of the (j + 2)-valent aromatic hydrocarbon group are groups obtained by removing (j + 2) hydrogen atoms from aromatic hydrocarbons such as benzene and naphthalene.

[0322] In formulas (d4) and (d5), j is an integer from 0 to 5.

[0323] Specific examples of the anions of the repeating units d4 and d5 are listed below, but are not limited to these. Also, in the following formulas, R A As described above, X BI is an iodine atom or a bromine atom.

[0324] [Chemical formula 92]

[0325]

[0326] [Chemical formula 93]

[0327]

[0328] [Chemical formula 94]

[0329]

[0330] [Chemical formula 95]

[0331]

[0332] [Chemical formula 96]

[0333]

[0334] [Chemical formula 97]

[0335]

[0336] [Chemical formula 98]

[0337]

[0338] [Chemical Formula 99]

[0339]

[0340] [Chemical Formula 100]

[0341]

[0342] [Chemical Formula 101]

[0343]

[0344] [Chemical Formula 102]

[0345]

[0346] [Chemical Formula 103]

[0347]

[0348] [Chemical Formula 104]

[0349]

[0350] [Chemical Formula 105]

[0351]

[0352] [Chemical Formula 106]

[0353]

[0354] [Chemical Formula 107]

[0355]

[0356] [Chemical Formula 108]

[0357]

[0358] [Chemical Formula 109]

[0359]

[0360] [Chemical Formula 110]

[0361]

[0362] [Chemical Formula 111]

[0363]

[0364] [Chemical Formula 112]

[0365]

[0366] [Chemical formula 113]

[0367]

[0368] [Chemical formula 114]

[0369]

[0370] [Chemical formula 115]

[0371]

[0372] [Chemical formula 116]

[0373]

[0374] [Chemical formula 117]

[0375]

[0376] [Chemical formula 118]

[0377]

[0378] [Chemical formula 119]

[0379]

[0380] [Chemical formula 120]

[0381]

[0382] [Chemical formula 121]

[0383]

[0384] [Chemical formula 122]

[0385]

[0386] [Chemical formula 123]

[0387]

[0388] [Chemical formula 124]

[0389]

[0390] [Chemical formula 125]

[0391]

[0392] [Chemical formula 126]

[0393]

[0394] [Chemical formula 127]

[0395]

[0396] [Chemical formula 128]

[0397]

[0398] [Chemical formula 129]

[0399]

[0400] [Chemical formula 130]

[0401]

[0402] [Chemical formula 131]

[0403]

[0404] [Chemical formula 132]

[0405]

[0406] [Chemical formula 133]

[0407]

[0408] [Chemical formula 134]

[0409]

[0410] [Chemical formula 135]

[0411]

[0412] [Chemical formula 136]

[0413]

[0414] [Chemical formula 137]

[0415]

[0416] [Chemical formula 138]

[0417]

[0418] [Chemical formula 139]

[0419]

[0420] [Chemical formula 140]

[0421]

[0422] [Chemical formula 141]

[0423]

[0424] [Chemical formula 142]

[0425]

[0426] [Chemical formula 143]

[0427]

[0428] In formulas (d2) to (d5), M + is a sulfonium cation or an oxonium cation. It is preferable that the aforementioned sulfonium cation is represented by the following formula (M1), and it is more preferable that the aforementioned oxonium cation is represented by the following formula (M2).

[0429] [Chemical formula 144]

[0430]

[0431] In formulas (M1) and (M2), R 41 to R 45 are each independently a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms which may also contain a heteroatom.

[0432] R 41 to R 45 Specific examples of the halogen atom represented by include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc.

[0433] R 41 to R 45The hydrocarbon group having 1 to 20 carbon atoms represented may be saturated or unsaturated, and may be linear, 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, icosyl; cycloaliphatic saturated hydrocarbon groups having 3 to 20 carbon atoms such as cyclopropyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norbornyl, adamantyl; alkenyl groups having 2 to 20 carbon atoms such as vinyl, propenyl, butenyl, hexenyl; alkynyl groups having 2 to 20 carbon atoms such as ethynyl, propynyl, butynyl; cycloaliphatic unsaturated aliphatic hydrocarbon groups having 3 to 20 carbon atoms such as cyclohexenyl, norbornenyl; aryl groups having 6 to 20 carbon atoms such as phenyl, methylphenyl, ethylphenyl, n-propylphenyl, isopropylphenyl, n-butylphenyl, isobutylphenyl, sec-butylphenyl, tert-butylphenyl, naphthyl, methylnaphthyl, ethylnaphthyl, n-propylnaphthyl, isopropylnaphthyl, n-butylnaphthyl, isobutylnaphthyl, sec-butylnaphthyl, tert-butylnaphthyl; aralkyl groups having 7 to 20 carbon atoms such as benzyl, phenethyl; groups obtained by combining them, and the like.

[0434] Further, some 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, 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, 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 mercapto group, a pentafluorohydrothio 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, and the like.

[0435] Further, R 41 and R 42 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 preferably has the following structure.

[0436] [Chemical formula 145]

[0437]

[0438] In the formula, the dashed line represents a bonding hand.

[0439] M + Specific examples of the sulfonium cation represented are listed below, but are not limited to these.

[0440] [Chemical formula 146]

[0441]

[0442] [Chemical formula 147]

[0443]

[0444] [Chemical 148]

[0445]

[0446] [Chemical 149]

[0447]

[0448] [Chemical 150]

[0449]

[0450] [Chemical 151]

[0451]

[0452] [Chemical 152]

[0453]

[0454] [Chemical 153]

[0455]

[0456] [Chemical 154]

[0457]

[0458] [Chemical 155]

[0459]

[0460] [Chemical 156]

[0461]

[0462] [Chemical 157]

[0463]

[0464] [Chemical 158]

[0465]

[0466] [Chemical 159]

[0467]

[0468] [Chemical 160]

[0469]

[0470] [Chemical 161]

[0471]

[0472] [Chemical Formula 162]

[0473]

[0474] [Chemical Formula 163]

[0475]

[0476] [Chemical Formula 164]

[0477]

[0478] [Chemical Formula 165]

[0479]

[0480] [Chemical Formula 166]

[0481]

[0482] [Chemical Formula 167]

[0483]

[0484] [Chemical Formula 168]

[0485]

[0486] [Chemical Formula 169]

[0487]

[0488] [Chemical Formula 170]

[0489]

[0490] [Chemical Formula 171]

[0491]

[0492] [Chemical Formula 172]

[0493]

[0494] [Chemical Formula 173]

[0495]

[0496] [Chemical Formula 174]

[0497]

[0498] [Chemical Formula 175]

[0499]

[0500] [Chemical formula 176]

[0501]

[0502] [Chemical formula 177]

[0503]

[0504] [Chemical formula 178]

[0505]

[0506] [Chemical formula 179]

[0507]

[0508] [Chemical formula 180]

[0509]

[0510] M + Specific examples of the iodonium cations represented are listed below, but are not limited to these.

[0511] [Chemical formula 181]

[0512]

[0513] [Chemical formula 182]

[0514]

[0515] For the repeating unit d, it is the repeating unit d2, d4 or d5 and Z 3 、Z 7A 、Z 7B or M + Preferably contains at least 1 or more iodine atoms.

[0516] The repeating units d1 to d5 act as acid generators. By bonding the acid generator to the polymer main chain, the diffusion of the acid is reduced and the decrease in resolution due to the blur of acid diffusion can be prevented. Also, due to the uniform dispersion of the acid generator, LWR and CDU are improved. Further, when using a base polymer containing the repeating units d1 to d5 (i.e., a polymer-bonded acid generator), the blending of the additive acid generator described later can be omitted.

[0517] The aforementioned base polymer may further contain a repeating unit e that does not contain an amino group and contains an iodine atom. Monomers providing the repeating unit e are listed below, but are not limited to these. Also, in the following formula, R A As described above.

[0518] [Chemical 183]

[0519]

[0520] [Chemical 184]

[0521]

[0522] The aforementioned base polymer may also contain repeating unit f other than the aforementioned repeating units. Examples of repeating unit f include those derived from styrene, vinylnaphthalene, indene, vinylnaphthalene, coumarin, coumarone, etc.

[0523] In the aforementioned base polymer, the content ratios of repeating units a, b1, b2, c, d1, d2, d3, d4, d5, e, and f are preferably 0 < a ≤ 0.8, 0 ≤ b1 ≤ 0.8, 0 ≤ b2 ≤ 0.8, 0 ≤ b1 + b2 ≤ 0.8, 0 ≤ c ≤ 0.9, 0 ≤ d1 ≤ 0.5, 0 ≤ d2 ≤ 0.5, 0 ≤ d3 ≤ 0.5, 0 ≤ d4 ≤ 0.5, 0 ≤ d5 ≤ 0.5, 0 ≤ d1 + d2 + d3 + d4 + d5 ≤ 0.5, 0 ≤ e ≤ 0.5, and 0 ≤ f ≤ 0.5; more preferably 0.05 ≤ a ≤ 0.7, 0 ≤ b1 ≤ 0.7, 0 ≤ b2 ≤ 0.7, 0 ≤ b1 + b2 ≤ 0.7, 0 ≤ c ≤ 0.8, 0 ≤ d1 ≤ 0.4, 0 ≤ d2 ≤ 0.4, 0 ≤ d3 ≤ 0.4, 0 ≤ d4 ≤ 0.4, 0 ≤ d5 ≤ 0.4, 0 ≤ d1 + d2 + d3 + d4 + d5 ≤ 0.4, 0 ≤ e ≤ 0.4, and 0 ≤ f ≤ 0.4; even more preferably 0.07 ≤ a ≤ 0.6, 0 ≤ b1 ≤ 0.6, 0 ≤ b2 ≤ 0.6, 0 ≤ b1 + b2 ≤ 0.6, 0 ≤ c ≤ 0.7, 0 ≤ d1 ≤ 0.3, 0 ≤ d2 ≤ 0.3, 0 ≤ d3 ≤ 0.3, 0 ≤ d4 ≤ 0.3, 0 ≤ d5 ≤ 0.3, 0 ≤ d1 + d2 + d3 + d4 + d5 ≤ 0.3, 0 ≤ e ≤ 0.3, and 0 ≤ f ≤ 0.3. However, a + b1 + b2 + c + d1 + d2 + d3 + d4 + d5 + e + f = 1.0.

[0524] To synthesize the aforementioned base polymer, for example, monomers that give the aforementioned repeating units may be added with a radical polymerization initiator in an organic solvent and heated to carry out polymerization.

[0525] Organic solvents used during polymerization, such as toluene, benzene, tetrahydrofuran (THF), diethyl ether, dioxane, propylene glycol monomethyl ether, γ-butyrolactone, and their mixed solvents, etc. Polymerization initiators, such as 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.

[0526] When copolymerizing monomers containing hydroxyl groups, during polymerization, the hydroxyl groups can be pre-substituted with acetal groups that are easily deprotected by acids, such as ethoxyethoxy groups, and deprotection can also be carried out using weak acids and water after polymerization. They can also be pre-substituted with acetyl groups, formyl groups, pivaloyl groups, etc., and base hydrolysis can be carried out after polymerization.

[0527] When copolymerizing hydroxystyrene and hydroxyvinylnaphthalene, instead of using hydroxystyrene and hydroxyvinylnaphthalene, acetoxystyrene and acetoxyvinylnaphthalene can be used, and after polymerization, the acetoxy groups are deprotected by the aforementioned base hydrolysis to become hydroxystyrene and hydroxyvinylnaphthalene.

[0528] The base used during 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.

[0529] For the aforementioned base polymer, the polystyrene-equivalent weight-average molecular weight (Mw) obtained by gel permeation chromatography (GPC) using THF as a solvent is preferably 1000 to 500000, more preferably 2000 to 30000. If Mw is within the aforementioned range, the heat resistance of the resist film and its solubility in alkaline developer are good.

[0530] Furthermore, when the molecular weight distribution (Mw / Mn) in the aforementioned base polymer is broad, there are low-molecular-weight and high-molecular-weight polymers present, so there is a risk of foreign matter appearing in the pattern or the shape of the pattern deteriorating after exposure. As the pattern rules become finer and finer, the influence of Mw and Mw / Mn is likely to increase. Therefore, in order to obtain a positive resist material suitable for use with fine pattern sizes, the Mw / Mn of the aforementioned base polymer is 1.0 to 2.0, especially preferably a narrow dispersion of 1.0 to 1.5.

[0531] In order to obtain a narrow-dispersion polymer, in addition to the use of ordinary radical polymerization, living radical polymerization can also be used. Examples of living radical polymerization include nitroxide-mediated radical polymerization (NMP), atom transfer radical polymerization (ATRP), and reversible addition-fragmentation chain transfer (RAFT) polymerization.

[0532] The aforementioned base polymer may also contain two or more polymers having different composition ratios, Mw, and Mw / Mn. Further, a polymer containing repeating unit a and a polymer not containing repeating unit a may be blended.

[0533] [Organic solvent]

[0534] The positive resist material of the present invention may also contain an organic solvent. The aforementioned organic solvent is not particularly limited as long as it can dissolve the aforementioned respective components and the respective components described later. Specific examples of the aforementioned organic solvent include ketones such as cyclohexanone, cyclopentanone, methyl-2-n-pentyl ketone, and 2-heptanone described in paragraphs

[0144] to

[0145] of JP-A-2008-111103; alcohols such as 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, and diacetone alcohol; ethers such as propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol dimethyl ether, and diethylene glycol dimethyl ether; esters such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl lactate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, tert-butyl acetate, tert-butyl propionate, and propylene glycol monoter-butyl ether acetate; lactones such as γ-butyrolactone, etc.

[0535] In the positive 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.

[0536] [Acid generator]

[0537] The positive resist material of the present invention may also contain an acid generator that generates a strong acid (hereinafter also referred to as an additive acid generator). The strong acid referred to herein is a compound having sufficient acidity to cause a deprotection reaction of the acid-labile group of the base polymer.

[0538] The aforementioned acid generator, for example: a compound that generates acid upon exposure to actinic light or radiation (photoacid generator). Any compound that generates acid upon irradiation with high-energy rays can be used as the photoacid generator, but those that generate sulfonic acid, imidic acid, or methylated acid are preferred. Ideal photoacid generators include, for example, sulfonium salts, iodonium salts, sulfonyl diazomethane, N-sulfonyloxyimide, oxime-O-sulfonate type acid generators, etc. Specific examples of the photoacid generator are those described in paragraphs

[0122] to

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

[0539] Furthermore, as the photoacid generator, a sulfonium salt represented by the following formula (1-1) and an iodonium salt represented by the following formula (1-2) are also preferably used.

[0540] [Chemical Formula 185]

[0541]

[0542] In formulas (1-1) and (1-2), R 101 ~R 105 are each independently a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms which may contain a 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 are the same as the examples of the hydrocarbon group represented by R 41 ~R 45 described in the explanations of formulas (M1) and (M2). Also, a part or all of the hydrogen atoms of the aforementioned hydrocarbon group may be substituted with a group containing a hetero atom such as an oxygen atom, a sulfur atom, a nitrogen atom, or a halogen atom, and a part of -CH 2 - of the aforementioned hydrocarbon group may also be substituted with a group containing a hetero atom such as an oxygen atom, a sulfur atom, or a nitrogen atom. 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, etc. Furthermore, R 101 and R 102 may also be bonded to each other and form a ring together with the sulfur atom to which they are bonded. Specific examples of the aforementioned ring are the same as the examples of the ring that can be formed together with the sulfur atom to which R 41 and R 42 are bonded to each other described in the explanation of formula (M1).

[0543] Specific examples of the cation of the sulfonium salt represented by formula (1-1) are the same as the examples of the sulfonium cation represented by formula (M1). Specific examples of the cation of the iodonium salt represented by formula (1-2) are the same as the examples of the iodonium cation represented by formula (M2).

[0544] In formulas (1-1) and (1-2), Xa - is an anion selected from the following formulas (1A) to (1D).

[0545] [Chemical Formula 186]

[0546]

[0547] In formula (1A), R fa is a fluorine atom or a hydrocarbon group having 1 to 40 carbon atoms which may contain a heteroatom. The aforementioned hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof are the same as the examples of the hydrocarbon group represented by R fa1 described later in formula (1A').

[0548] The anion represented by formula (1A) is preferably the one represented by the following formula (1A').

[0549] [Chemical Formula 187]

[0550]

[0551] In formula (1A'), R HF is a hydrogen atom or a trifluoromethyl group, preferably a trifluoromethyl group. R fa1 is a hydrocarbon group having 1 to 38 carbon atoms which may 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 preferably has 6 to 30 carbon atoms.

[0552] The hydrocarbon group represented by R fa1 may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof include alkyl groups having 1 to 38 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, pentyl, neopentyl, hexyl, heptyl, 2-ethylhexyl, nonyl, undecyl, tridecyl, pentadecyl, heptadecyl, icosyl; cycloaliphatic 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; unsaturated aliphatic hydrocarbon groups having 2 to 38 carbon atoms such as allyl, 3-cyclohexenyl; aryl groups having 6 to 38 carbon atoms such as phenyl, 1-naphthyl, 2-naphthyl; aralkyl groups having 7 to 38 carbon atoms such as benzyl, diphenylmethyl; groups obtained by combining them, etc.

[0553] Furthermore, some 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 the -CH 2A part of it may also be substituted with a group containing a heteroatom such as an oxygen atom, a sulfur atom, or a nitrogen atom. 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. Specific examples of the hydrocarbon group containing a heteroatom include a tetrahydrofuranyl group, a methoxymethyl group, an ethoxymethyl group, a methylthiomethyl group, an acetamidomethyl group, a trifluoroethyl group, a (2-methoxyethoxy)methyl group, an acetoxymethyl group, a 2-carboxy-1-cyclohexyl group, a 2-oxopropyl group, a 4-oxo-1-adamantyl group, a 3-oxocyclohexyl group, etc.

[0554] Regarding the synthesis of the sulfonium salt containing the anion represented by the formula (1A'), 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. are also preferably used.

[0555] Specific examples of the anion represented by the formula (1A) are the same as the examples exemplified for the anion represented by the formula (1A) in Japanese Patent Application Laid-Open No. 2018-197853.

[0556] In the formula (1B), R fb1 and R fb2 are each independently 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 of it are the same as the examples exemplified for the hydrocarbon group represented by R fa1 in the formula (1A'). 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. In this case, the group obtained by bonding R fb1 and R fb2 to each other is preferably a fluoroethylene group or a fluoropropylene group.

[0557] In the formula (1C), R fc1 , R fc2 and Rfc3 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 linear, branched or cyclic. Specific examples thereof are the same as the hydrocarbon groups exemplified for R in formula (1A'). fa1 The hydrocarbon groups represented are the same examples as those exemplified above. R fc1 , R fc2 and R fc3 are preferably a fluorine atom or a linear fluorinated alkyl group having 1 to 4 carbon atoms. Further, 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. In this case, the group obtained by bonding R fc1 and R fc2 to each other is preferably a fluoroethylene or fluoropropylene group.

[0558] In formula (1D), 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 linear, branched or cyclic. Specific examples thereof are the same as the hydrocarbon groups exemplified for R in formula (1A'). fa1 The hydrocarbon groups represented are the same examples as those exemplified above.

[0559] For the synthesis of the sulfonium salt containing the anion represented by formula (1D), refer to Japanese Patent Application Laid-Open No. 2010-215608 and Japanese Patent Application Laid-Open No. 2014-133723 in detail.

[0560] Specific examples of the anion represented by formula (1D) are the same as those exemplified for the anion represented by formula (1D) in Japanese Patent Application Laid-Open No. 2018-197853.

[0561] Further, the photoacid generator containing the anion represented by formula (1D) has no fluorine atom at the α-position of the sulfo group but has two trifluoromethyl groups at the β-position, and thus has sufficient acidity to cleave the acid-labile group in the base polymer. Therefore, it can be used as a photoacid generator.

[0562] A photoacid generator is also preferably one represented by the following formula (2).

[0563] [Chemical formula 188]

[0564]

[0565] In formula (2), R 201 and R 202Each independently represents a halogen atom or a hydrocarbon group having 1 to 30 carbon atoms which may also contain a heteroatom. R 203 is an alkylene group having 1 to 30 carbon atoms which may also contain a heteroatom. Further, R 201 , R 202 and R 203 Any two of them may also be bonded to each other and together with the sulfur atom to which they are bonded form a ring. Specific examples of the ring at this time are the same as the examples of the ring which can be formed together with the sulfur atom to which they are bonded when explaining R 2 and R 3 bonded in the formula (a).

[0566] The hydrocarbon groups represented by R 201 and R 202 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; cycloalkyl saturated hydrocarbon groups having 3 to 30 carbon atoms such as cyclopentyl, cyclohexyl, cyclopentylmethyl, cyclopentylethyl, cyclopentylbutyl, cyclohexylmethyl, cyclohexylethyl, cyclohexylbutyl, norbornyl, tricyclo[5.2.1.0 2,6 decyl, 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; groups obtained by combining them. Further, 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, and part of -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, 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.

[0567] R 203The represented alkylene group can be saturated or unsaturated, and can be linear, branched or cyclic. Specific examples thereof include alkanediyl groups having 1 to 30 carbon atoms 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; cycloaliphatic saturated alkylene groups having 3 to 30 carbon atoms such as cyclopentanediyl, cyclohexanediyl, norbornanediyl, adamantanediyl; arylene groups having 6 to 30 carbon atoms such as phenylene, methylphenylene, ethylphenylene, n-propylphenylene, isopropylphenylene, n-butylphenylene, isobutylphenylene, sec-butylphenylene, tert-butylphenylene, naphthylene, methylnaphthylene, ethylnaphthylene, n-propylnaphthylene, isopropylnaphthylene, n-butylnaphthylene, isobutylnaphthylene, sec-butylnaphthylene, tert-butylnaphthylene; groups obtained by combining them. Also, some or all of the hydrogen atoms of the aforementioned alkylene group can be substituted with groups containing heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, and halogen atoms, and a part of -CH 2 - of the aforementioned alkylene group can also be substituted with groups containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. As a result, it can also contain hydroxyl groups, fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, cyano groups, nitro groups, carbonyl groups, ether bonds, ester bonds, sulfonate ester bonds, carbonate ester bonds, lactone rings, sultone rings, carboxylic anhydrides (-C(=O)-O-C(=O)-), haloalkyl groups, etc. The aforementioned heteroatom is preferably an oxygen atom.

[0568] In formula (2), L C is a single bond, an ether bond, or an alkylene group having 1 to 20 carbon atoms that can also contain heteroatoms. The aforementioned alkylene group can be saturated or unsaturated, and can be linear, branched or cyclic. Specific examples thereof are the same as the examples exemplified for the alkylene group represented by R 203

[0569] In formula (2), 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.

[0570] In formula (2), k is an integer from 0 to 3. ​

[0571] The photoacid generator represented by formula (2) is preferably the one represented by the following formula (2').

[0572] [Chemical 189]

[0573]

[0574] In formula (2'), L C is as described above. X E is a hydrogen atom or a trifluoromethyl group, 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, unsaturated, straight-chain, branched-chain, or cyclic. Specific examples thereof are the same as the examples exemplified for the hydrocarbon group represented by R fa1 in formula (1A'). k1 and k2 are each independently an integer of 0 to 5, and k3 is an integer of 0 to 4.

[0575] Specific examples of the photoacid generator represented by formula (2) are the same as the examples exemplified for the photoacid generator represented by formula (2) in Japanese Patent Laid-Open No. 2017-026980.

[0576] Among the aforementioned photoacid generators, those containing an anion represented by formula (1A') or (1D) have small acid diffusion and excellent solubility in solvents, and are particularly desirable. Also, those represented by formula (2') have extremely small acid diffusion and are particularly desirable.

[0577] The aforementioned photoacid generator may also be 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 are those represented by the following formula (3-1) or (3-2).

[0578] [Chemical 190]

[0579]

[0580] In formula (3-1) and (3-2), p is an integer satisfying 1 ≤ p ≤ 3. q and r are integers satisfying 1 ≤ q ≤ 5, 0 ≤ r ≤ 3, and 1 ≤ q + r ≤ 5. It is more desirable that q is an integer satisfying 1 ≤ q ≤ 3, and 2 or 3 is even more desirable. It is preferable that r is an integer satisfying 0 ≤ r ≤ 2.

[0581] In formula (3-1) and (3-2), X BI is an iodine atom or a bromine atom, and when p and / or q is 2 or more, they may be the same or different from each other.

[0582] In formula (3-1) and (3-2), L 11is a single bond, an ether bond or an ester bond, or a saturated alkylene group having 1 to 6 carbon atoms which may also contain an ether bond or an ester bond. The aforementioned saturated alkylene group may be linear, branched or cyclic.

[0583] In formulas (3-1) and (3-2), L 12 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. The linking group may also contain an oxygen atom, a sulfur atom or a nitrogen atom.

[0584] In formulas (3-1) and (3-2), R 401 is a hydroxyl group, a carboxyl group, a fluorine atom, a chlorine atom, a bromine atom or an amino group, or a hydrocarbon group having 1 to 20 carbon atoms, a 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 which 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 401C is a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms, and may also contain a halogen atom, a hydroxyl group, a saturated hydrocarbon oxy group having 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl group having 2 to 6 carbon atoms or a saturated hydrocarbon carbonyloxy 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 oxy group having 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl group having 2 to 6 carbon atoms or a saturated hydrocarbon carbonyloxy 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 oxy group, hydrocarbon carbonyl group, hydrocarbon oxycarbonyl group, hydrocarbon carbonyloxy group and hydrocarbon sulfonyloxy group may be linear, branched or cyclic. When p and / or r is 2 or more, each R 401 may be the same or different from each other.

[0585] Among these, 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 and the like.

[0586] In formulas (3-1) and (3-2), Rf 11 ~Rf 14 are each independently a hydrogen atom, a fluorine atom or a trifluoromethyl group, provided that at least one of these is a fluorine atom or a trifluoromethyl group. Further, Rf 11 and Rf 12 may also combine to form a carbonyl group. In particular, it is preferable that both Rf 13 and Rf 14 are fluorine atoms.

[0587] In formulas (3-1) and (3-2), 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 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 linear, branched or cyclic. Specific examples thereof are the same as the examples of the hydrocarbon group represented in the description of formula (a) for R 2 ~R 4 . Further, 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. Furthermore, 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. Specific examples of the aforementioned ring at this time are the same as the examples of the ring that can be formed together with the sulfur atom to which R 41 and R 42 are bonded to each other as illustrated in the description of formula (M1).

[0588] Specific examples of the cation of the sulfonium salt represented by formula (3-1) are the same as the examples of the sulfonium cation represented by M + as illustrated in the description of formulas (d2) to (d5). Further, specific examples of the cation of the oxosulfonium salt represented by formula (3-2) are the same as the examples of the oxosulfonium cation represented by M + as illustrated in the description of formulas (d2) to (d5).

[0589] Specific examples of the anion of the onium salt represented by formula (3-1) or (3-2) are the same as the examples of the anion represented by formula (d1-3).

[0590] As the aforementioned photoacid generator, a sulfonium salt or an oxosulfonium salt of fluorobenzenesulfonic acid bonded to iodobenzoic acid represented by the following formula (3-3) or (3-4) may also be used.

[0591] [Chemical formula 191]

[0592]

[0593] In formulas (3-3) and (3-4), s is an integer from 1 to 5, t is an integer from 0 to 3, and u is an integer from 1 to 4.

[0594] In formulas (3-3) and (3-4), R 411 is a hydroxyl group, a carboxyl group, an alkoxycarbonyl group, a fluorine atom, a chlorine atom, a bromine atom, an amino group, or a saturated hydrocarbon group having 1 to 20 carbon atoms, a saturated hydrocarbon oxy group having 1 to 20 carbon atoms, or a saturated hydrocarbon carbonyloxy group having 2 to 20 carbon atoms, which 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 . R 411A is a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms. R 411B 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, which may also contain a halogen atom, a hydroxyl group, a saturated hydrocarbon oxy group having 1 to 6 carbon atoms, a saturated hydrocarbon carbonyl group having 2 to 6 carbon atoms, or a saturated hydrocarbon carbonyloxy group having 2 to 6 carbon atoms.

[0595] In formulas (3-3) and (3-4), L 3 is a single bond or a divalent linking group having 1 to 20 carbon atoms, which may also contain an oxygen atom, a sulfur atom or a nitrogen atom.

[0596] In formulas (3-3) and (3-4), Rf 21 is a fluorine atom or a trifluoromethyl group.

[0597] In formulas (3-3) and (3-4), R 412 to R 416 are each independently a halogen atom, or a hydrocarbon group having 1 to 20 carbon atoms which may also contain a heteroatom. Specific examples of the foregoing halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. The foregoing hydrocarbon group may be saturated or unsaturated, and may be linear, branched or cyclic. Specific examples thereof are the same as the hydrocarbon groups exemplified for R 2 to R 4 in the description of formula (a). Also, a part or all of the hydrogen atoms of the foregoing 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 foregoing 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. Furthermore, R 402 and R 403They can also be bonded to each other and together with the sulfur atoms to which they are bonded to form a ring. Specific examples of the aforementioned ring are the same as those exemplified for the ring formed by bonding to R and the sulfur atoms to which they are bonded in the description of formula (a). 2 and R 3 Specific examples of the ring formed by bonding to and together with the sulfur atoms to which they are bonded are the same examples as those exemplified in the description of formula (d2)-(d5) for the sulfonium cation represented by M

[0598] Specific examples of the cation of the sulfonium salt represented by formula (3-3) are the same examples as those exemplified for the sulfonium cation represented by M in the description of formula (d2)-(d5). Also, specific examples of the cation of the oxosulfonium salt represented by formula (3-4) are the same examples as those exemplified for the oxosulfonium cation represented by M in the description of formula (d2)-(d5). + Specific examples of the anion of the onium salt represented by formula (3-3) or (3-4) are listed below, but are not limited to these. + Specific examples of the cation of the oxosulfonium salt represented by formula (3-4) are the same examples as those exemplified for the oxosulfonium cation represented by M in the description of formula (d2)-(d5).

[0599] Specific examples of the anion of the onium salt represented by formula (3-3) or (3-4) can be listed as follows, but are not limited to these.

[0600] [Chemical formula 192]

[0601]

[0602] [Chemical formula 193]

[0603]

[0604] [Chemical formula 194]

[0605]

[0606] [Chemical formula 195]

[0607]

[0608] [Chemical formula 196]

[0609]

[0610] When the positive resist material of the present invention contains the aforementioned additive acid generator, 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 aforementioned additive acid generator can be used alone or in combination of two or more. The positive resist material of the present invention can function as a chemically amplified positive resist material by containing any of the repeating units d1-d5 in the aforementioned base polymer and / or by containing an additive acid generator.

[0611] [Quencher]

[0612] The positive resist material of the present invention may also contain a quencher. Also, a quencher is a compound that can prevent the acid from diffusing to the unexposed portion by capturing the acid generated from the acid generator in the resist material.

[0613] The aforementioned quencher is, for example, a basic compound of a known type. Specific examples of basic compounds of a known type include, for example, primary, secondary, and 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, and the like. In particular, the primary, secondary, and tertiary amine compounds described in paragraphs

[0146] to

[0164] of Japanese Patent Laid-Open No. 2008-111103, especially amine compounds having a hydroxyl group, an ether bond, an ester bond, a lactone ring, a cyano group, a sulfonate bond, or the compounds having a urethane bond described in Japanese Patent No. 3790649 are preferable. 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.

[0614] Furthermore, the aforementioned quencher is, for example, a sulfonium salt, a phosphonium salt, an ammonium salt, etc. of a sulfonic acid, a carboxylic acid, or a fluorinated alkoxide that is not fluorinated at the α-position, as described in Japanese Patent Laid-Open No. 2008-158339. Sulfonic acids, imidic acids, or methylated acids that are fluorinated at the α-position are necessary for deprotecting the acid-labile group of the carboxylic ester, but due to salt exchange with the aforementioned onium salts, sulfonic acids, carboxylic acids, or fluorinated alcohols that are not fluorinated at the α-position are released. Sulfonic acids, carboxylic acids, and fluorinated alcohols that are not fluorinated at the α-position do not undergo a deprotection reaction and thus act as quenchers.

[0615] Specific examples of such quenchers include, for example, the compound represented by the following formula (4) (onium salt of a sulfonic acid that is not fluorinated at the α-position), the compound represented by the following formula (5) (onium salt of a carboxylic acid), and the compound represented by the following formula (6) (onium salt of an alkoxide).

[0616] [Chemical Formula 197]

[0617]

[0618] In formula (4), R 501 is a hydrogen atom or a hydrocarbon group having 1 to 40 carbon atoms that may contain a heteroatom, provided that the hydrogen atom bonded to the carbon atom at the α-position excluding the sulfonyl group is not substituted by a fluorine atom or a fluoroalkyl group.

[0619] R 501The hydrocarbon group having 1 to 40 carbon atoms represented may be saturated or unsaturated, and may be linear, branched or cyclic. Specific examples thereof include alkyl groups having 1 to 40 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, tert-pentyl, n-hexyl, n-octyl, 2-ethylhexyl, n-nonyl, n-decyl, etc.; cycloaliphatic saturated hydrocarbon groups having 3 to 40 carbon atoms such as cyclopentyl, cyclohexyl, cyclopentylmethyl, cyclopentylethyl, cyclopentylbutyl, cyclohexylmethyl, cyclohexylethyl, cyclohexylbutyl, norbornyl, tricyclo[5.2.1.0 2,6 decyl, adamantyl, adamantylmethyl, etc.; alkenyl groups having 2 to 40 carbon atoms such as vinyl, allyl, propenyl, butenyl, hexenyl, etc.; cycloaliphatic unsaturated aliphatic hydrocarbon groups having 3 to 40 carbon atoms such as cyclohexenyl; aryl groups having 6 to 40 carbon atoms such as phenyl, naphthyl, alkylphenyl (2-methylphenyl, 3-methylphenyl, 4-methylphenyl, 4-ethylphenyl, 4-tert-butylphenyl, 4-n-butylphenyl, etc.), di- or tri-alkylphenyl (2,4-dimethylphenyl, 2,4,6-triisopropylphenyl, etc.), alkylnaphthyl (methylnaphthyl, ethylnaphthyl, etc.), di-alkylnaphthyl (dimethylnaphthyl, diethylnaphthyl, etc.); aralkyl groups having 7 to 40 carbon atoms such as benzyl, 1-phenylethyl, 2-phenylethyl, etc.

[0620] Furthermore, 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, 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 also contain a hydroxyl group, a cyano group, a carbonyl group, an ether bond, an ester bond, a sulfonate bond, a carbonate bond, a lactone ring, a sultone ring, a carboxylic anhydride (-C(=O)-O-C(=O)-), a haloalkyl group, etc. Specific examples of the hydrocarbon group containing a heteroatom include heteroaryl groups such as thienyl; alkoxyphenyl groups such as 4-hydroxyphenyl, 4-methoxyphenyl, 3-methoxyphenyl, 2-methoxyphenyl, 4-ethoxyphenyl, 4-tert-butoxyphenyl, 3-tert-butoxyphenyl; alkoxynaphthyl groups such as methoxynaphthyl, ethoxynaphthyl, n-propoxynaphthyl, n-butoxynaphthyl; dialkoxynaphthyl groups such as dimethoxynaphthyl, diethoxynaphthyl; aryl oxoalkyl groups such as 2-aryl-2-oxoethyl groups such as 2-phenyl-2-oxoethyl, 2-(1-naphthyl)-2-oxoethyl, 2-(2-naphthyl)-2-oxoethyl, etc.

[0621] In formula (5), R 502 is a hydrocarbon group having 1 to 40 carbon atoms which may also contain a heteroatom. Specific examples of the hydrocarbon group represented by R 502 are, for example, the same as those of R 101Examples of the represented hydrocarbon groups are the same examples. Further, as other specific examples, fluorinated alkyl groups such as trifluoromethyl, trifluoroethyl, 2,2,2-trifluoro-1-methyl-1-hydroxyethyl, 2,2,2-trifluoro-1-(trifluoromethyl)-1-hydroxyethyl, etc.; fluorinated aryl groups such as pentafluorophenyl, 4-trifluoromethylphenyl, etc. can be cited.

[0622] In formula (6), R 503 is a saturated hydrocarbon group having 1 to 8 carbon atoms and having at least 3 fluorine atoms or an aryl group having 6 to 10 carbon atoms and having at least 3 fluorine atoms, and may contain a nitro group.

[0623] In formulas (4), (5) and (6), Mq + is an onium cation. It is preferable that the onium cation is a sulfonium cation, an iodonium cation or an ammonium cation, and more preferably a sulfonium cation. Specific examples of the sulfonium cation are the same as the examples shown for M in the description of formulas (d2) to (d5). + Examples of the sulfonium cation represented are the same examples.

[0624] As the quencher, a sulfonium salt of a carboxylic acid containing an iodinated benzene ring represented by the following formula (7) is also preferably used.

[0625] [Chemical formula 198]

[0626]

[0627] In formula (7), x is an integer of 1 to 5. y is an integer of 0 to 3. z is an integer of 1 to 3.

[0628] In formula (7), R 511 is a hydroxyl group, a fluorine atom, a chlorine atom, a bromine atom, an amino group, a nitro group, a cyano group, or a saturated hydrocarbon group having 1 to 6 carbon atoms, a saturated hydrocarbon oxy group having 1 to 6 carbon atoms, a saturated hydrocarbon carbonyloxy group having 2 to 6 carbon atoms or a saturated hydrocarbon sulfonyloxy group having 1 to 4 carbon atoms, in which part or all of the hydrogen atoms may be substituted by halogen atoms, or -N(R 511A )-C(=O)-R 511B or -N(R 511A )-C(=O)-O-R 511B . R 511A is a hydrogen atom or a saturated hydrocarbon group having 1 to 6 carbon atoms. R 511B is a saturated hydrocarbon group having 1 to 6 carbon atoms or an unsaturated aliphatic hydrocarbon group having 2 to 8 carbon atoms. When y and / or z is 2 or more, each R 511 may be the same or different from each other.

[0629] In formula (7), L 21is a single bond or a (z + 1)-valent linking group having 1 to 20 carbon atoms, and may also contain at least one selected from an ether bond, a carbonyl group, an ester bond, an amide bond, a sultone ring, a lactam ring, a carbonate bond, a halogen atom, a hydroxyl group, and a carboxyl group. The aforementioned saturated hydrocarbon group, saturated hydrocarbon oxy group, saturated hydrocarbon carbonyloxy group, and saturated hydrocarbon sulfonyloxy group may be linear, branched, or cyclic.

[0630] In formula (7), R 512 , R 513 and R 514 are each independently a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms which may also contain a hetero atom. The aforementioned hydrocarbon group may be saturated or unsaturated, and may be linear, branched, or cyclic. Specific examples thereof are the same as the examples of the hydrocarbon group represented by R 41 to R 45 described in the explanations of formulas (M1) and (M2).

[0631] Specific examples of the cation of the sulfonium salt represented by (7) are the same as the examples of the sulfonium cation represented by M + described in the explanations of formulas (d2) to (d5).

[0632] Specific examples of the sulfonium salt represented by formula (7) are those described in JP-A-2017-219836 and JP-A-2021-91666.

[0633] Other examples of the quencher include, for example, the polymer-type quencher described in JP-A-2008-239918. By aligning on the surface of the resist film, the rectangularity of the resist pattern is improved. The polymer-type quencher also has the effect of preventing pattern film loss and rounding of the pattern top when using a protective film for immersion exposure.

[0634] Furthermore, a betaine-type sulfonium salt described in Japanese Patent No. 6848776 and JP-A-2020-37544, a methylation acid without a fluorine atom described in JP-A-2020-55797, a sulfonium salt of sulfonamide described in Japanese Patent No. 5807552, a sulfonium salt of an iodine atom-containing sulfonamide described in JP-A-2019-211751, phenol, a halogen, or an acid generator that generates an acid from carbon can be used as a quencher.

[0635] When the positive resist material of the present invention contains the aforementioned quencher, its content is preferably 0 to 5 parts by mass, more preferably 0 to 4 parts by mass, relative to 100 parts by mass of the base polymer. The aforementioned quencher may be used alone or in combination of two or more.

[0636] [Other components]

[0637] In addition to containing the aforementioned components, the positive resist material of the present invention may further contain a surfactant, a dissolution inhibitor, a water repellency enhancer, acetylene alcohols, etc.

[0638] Specific examples of the aforementioned surfactant are those described in paragraphs

[0165] to

[0166] of Japanese Patent Laid-Open No. 2008-111103. By adding a surfactant, the coatability of the resist material can be improved or controlled. When the positive resist material of the present invention contains a 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.

[0639] In the positive resist material of the present invention, by blending a dissolution inhibitor, the difference in dissolution rate between the exposed portion and the unexposed portion can be made larger, and the resolution can be further improved. Specific examples of the aforementioned dissolution inhibitor are compounds having a molecular weight preferably of 100 to 1,000, more preferably 150 to 800 and containing two or more phenolic hydroxyl groups in the molecule, and the hydrogen atoms of the phenolic hydroxyl groups are replaced by acid-labile groups in a proportion of 0 to 100 mol% in total, or compounds containing a carboxyl group in the molecule, and the hydrogen atoms of the carboxyl group are replaced by acid-labile groups in an average proportion of 50 to 100 mol% in total. Specifically, for example, compounds in which the hydrogen atoms of the hydroxyl groups and carboxyl groups of bisphenol A, triphenol, phenolphthalein, cresol novolac, naphthoic acid, adamantane carboxylic acid, cholic acid are replaced by acid-labile groups, etc., for example, those described in paragraphs

[0155] to

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

[0640] When the positive resist material of the present invention contains the aforementioned dissolution inhibitor, its content is preferably 0 to 50 parts by mass, more preferably 5 to 40 parts by mass relative to 100 parts by mass of the base polymer. The aforementioned dissolution inhibitor may be used alone or in combination of two or more.

[0641] The aforementioned water repellency enhancer is one that enhances the water repellency of the surface of the resist film and can be used in immersion lithography without using a top coat. It is preferable that the aforementioned water repellency enhancer is a polymer compound containing a fluorinated alkyl group, a polymer compound containing a 1,1,1,3,3,3-hexafluoro-2-propanol residue with a specific structure, etc., and those exemplified in Japanese Patent Laid-Open No. 2007-297590, Japanese Patent Laid-Open No. 2008-111103, etc. are more preferable. The aforementioned water repellency enhancer needs to be dissolved in an alkali developer or an organic solvent developer. The aforementioned specific water repellency enhancer having a 1,1,1,3,3,3-hexafluoro-2-propanol residue has good solubility in the developer. Regarding the water repellency enhancer, a polymer compound containing repeating units of amino group and amine salt has a high effect of preventing the evaporation of acid during post-exposure bake (PEB) and preventing the opening defect of the hole pattern after development. When the positive resist material of the present invention contains the aforementioned water repellency enhancer, its content is preferably 0 to 20 parts by mass, more preferably 0.5 to 10 parts by mass, relative to 100 parts by mass of the base polymer. The aforementioned water repellency enhancer can be used alone or in combination of two or more kinds.

[0642] Specific examples of the aforementioned acetylene alcohols are those described in paragraphs

[0179] to

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

[0643] [Pattern formation method]

[0644] When the positive resist material of the present invention is used in the manufacture of various integrated circuits, known lithography techniques can be adopted. For example: The pattern formation method may include a method including a step of forming a resist film on a substrate using the aforementioned positive resist material of the present invention, a step of exposing the aforementioned resist film with high-energy rays, and a step of developing the exposed resist film using a developer.

[0645] First, the positive resist material of the present invention is coated by an appropriate coating method such as spin coating, roll coating, flow coating, dip coating, spray coating, blade coating, etc. so that the coating thickness becomes 0.01 to 2 μm 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 2 , etc.). It is prebaked on a hot plate, preferably under the conditions 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.

[0646] Next, the resist film is exposed using high-energy rays. Specific examples of the high-energy rays include, for example, ultraviolet rays, far ultraviolet rays, electron beams (EB), EUV with a wavelength of 3 to 15 nm, X-rays, soft X-rays, excimer lasers, γ-rays, synchrotron radiation, etc. When using ultraviolet rays, far ultraviolet rays, EUV, X-rays, soft X-rays, excimer lasers, γ-rays, synchrotron radiation, etc. as the high-energy rays, it is directly or used with a mask for forming a target pattern, and the exposure dose is preferably about 1 to 200 mJ / cm 2 , more preferably about 10 to 100 mJ / cm 2 for irradiation. When the high-energy ray is an electron beam (EB), the exposure dose is preferably about 0.1 to 300 μC / cm 2 , more preferably about 0.5 to 200 μC / cm 2 , and it is directly or used with a mask for forming a target pattern for drawing. Further, the positive 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 among high-energy rays, and is particularly suitable for fine patterning by EB or EUV.

[0647] After exposure, PEB can also be carried out on a hot plate or in an oven, preferably under the conditions of 30 to 150 °C for 10 seconds to 30 minutes, more preferably 50 to 120 °C for 30 seconds to 20 minutes, or it can also not be carried out.

[0648] After exposure or after PEB, a developer of an alkaline aqueous solution such as 0.1 to 10% by mass, preferably 2 to 5% by mass of tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, etc. is used, and the exposed resist film is developed by a conventional method such as the dip method, puddle method, spray method, etc. for 3 seconds to 3 minutes, preferably 5 seconds to 2 minutes, so that the irradiated part is dissolved in the developer and the unexposed part is not dissolved, and a target pattern is formed on the substrate.

[0649] A positive resist material containing a base polymer having an acid-labile group can also be used, and a negative pattern can be obtained by developing with an organic solvent. Specific examples of the developing solution used at this time are, for example, 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.

[0650] Rinsing is carried out at the end of development. It is preferable that the rinsing solution is a solvent that is miscible with the developing solution and does not dissolve the resist film. As such a solvent, alcohols having 3 to 10 carbon atoms, ether compounds having 8 to 12 carbon atoms, alkanes, alkenes, alkynes, and aromatic solvents having 6 to 12 carbon atoms are ideal.

[0651] Specific examples of the alcohols having 3 to 10 carbon atoms are, for example, 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.

[0652] Specific examples of the ether compounds having 8 to 12 carbon atoms are, for example, 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.

[0653] 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.

[0654] Specific examples of the aromatic solvents include toluene, xylene, ethylbenzene, isopropylbenzene, tert-butylbenzene, mesitylene, etc.

[0655] By performing rinsing, collapse and occurrence of defects of the resist pattern can be reduced. Further, rinsing is not necessary, and by not performing rinsing, the usage amount of the solvent can be reduced.

[0656] The developed hole pattern and trench pattern can also be shrunk by using heat flow, RELACS technology or DSA technology. A shrinkage agent is applied to the hole pattern, and by diffusion of the acid catalyst from the resist film during baking, crosslinking of the shrinkage agent occurs on the surface of the resist film, and the shrinkage agent adheres to the side wall of the hole pattern. The baking temperature is preferably 70 to 180 °C, more preferably 80 to 170 °C, and the baking time is preferably 10 to 300 seconds, and the excess shrinkage agent is removed to shrink the hole pattern.

[0657] Examples

[0658] The following synthesis examples, examples and comparative examples specifically illustrate the present invention, and the present invention is not limited by the following examples.

[0659] [1] Synthesis of Polymer

[0660] The acid-labile group-protected vinyl salicylic acid-based monomers a-1 to a-8, monomers ALG-1 and ALG-2 having an acid-labile group, and monomers PM-1 to PM-12 having an acid-generating group used for the synthesis of the polymer are as follows. Further, Mw of the polymer is a polystyrene-converted measured value measured by GPC using THF as a solvent.

[0661] [Chemical formula 199]

[0662]

[0663] [Chemical formula 200]

[0664]

[0665] [Chemical formula 201]

[0666]

[0667] [Chemical formula 202]

[0668]

[0669] [Synthesis Example 1] Synthesis of Polymer P-1

[0670] In a 2 L flask, 4.2 g of monomer a-1, 5.9 g of 1-methyl-1-cyclopentyl methacrylate, 6.0 g of 3-hydroxystyrene, and 40 g of THF as a solvent were added. This reaction vessel was cooled to -70 °C under a nitrogen atmosphere, and degassing under reduced pressure and nitrogen purging were repeated 3 times. After warming to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C and allowed to react for 15 hours. This reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The obtained white solid was dried under reduced pressure at 60 °C to obtain Polymer P-1. The composition of Polymer P-1 was confirmed by 13 C-NMR and 1 H-NMR, and Mw and Mw / Mn were confirmed by GPC.

[0671] [Chemical formula 203]

[0672]

[0673] [Synthesis Example 2] Synthesis of Polymer P-2

[0674] In a 2 L flask, 4.2 g of monomer a-1, 8.8 g of ALG-1, 5.4 g of 4-hydroxystyrene, and 40 g of THF as a solvent were added. This reaction vessel was cooled to -70 °C under a nitrogen atmosphere, and degassing under reduced pressure and nitrogen purging were repeated 3 times. After warming to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C and allowed to react for 15 hours. This reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The obtained white solid was dried under reduced pressure at 60 °C to obtain Polymer P-2. The composition of Polymer P-2 was confirmed by 13 C-NMR and 1 H-NMR, and Mw and Mw / Mn were confirmed by GPC.

[0675] [Chemical formula 204]

[0676]

[0677] [Synthesis Example 3] Synthesis of Polymer P-3

[0678] 6.1 g of monomer a-2, 5.9 g of 1-methyl-1-cyclopentyl methacrylate, 4.8 g of 3-hydroxystyrene, 8.5 g of monomer PM-1, and 40 g of THF as a solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under a nitrogen atmosphere, and degassing under reduced pressure and nitrogen purging were repeated three times. After warming to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C to react for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The obtained white solid was dried under reduced pressure at 60 °C to obtain polymer P-3. The composition of polymer P-3 was confirmed by 13 C-NMR and 1 H-NMR, and Mw and Mw / Mn were confirmed by GPC.

[0679] [Chemical Formula 205]

[0680]

[0681] [Synthesis Example 4] Synthesis of Polymer P-4

[0682] 3.1 g of monomer a-3, 7.6 g of 1-methyl-1-cyclopentyl methacrylate, 4.2 g of 3-hydroxystyrene, 9.7 g of monomer PM-2, and 40 g of THF as a solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under a nitrogen atmosphere, and degassing under reduced pressure and nitrogen purging were repeated three times. After warming to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C to react for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was filtered. The obtained white solid was dried under reduced pressure at 60 °C to obtain polymer P-4. The composition of polymer P-4 was confirmed by 13 C-NMR and 1 H-NMR, and Mw and Mw / Mn were confirmed by GPC.

[0683] [Chemical Formula 206]

[0684]

[0685] [Synthesis Example 5] Synthesis of Polymer P-5

[0686] Add 4.4 g of monomer a-4, 4.1 g of 1-methyl-1-cyclopentyl methacrylate, 4.8 g of 4-hydroxystyrene, 10.9 g of monomer PM-3, and 40 g of THF as a solvent to a 2 L flask. Cool this reaction vessel to -70 °C under a nitrogen atmosphere, and repeat the procedures of vacuum degassing and nitrogen purging three times. After warming up to room temperature, add 1.2 g of AIBN as a polymerization initiator, and heat up to 60 °C to allow the reaction to proceed for 15 hours. Add this reaction solution to 1 L of isopropanol, and filter out the precipitated white solid. Dry the obtained white solid under reduced pressure at 60 °C to obtain polymer P-5. The composition of polymer P-5 was confirmed by 13 C-NMR and 1 H-NMR, and Mw and Mw / Mn were confirmed by GPC.

[0687] [Chemical formula 207]

[0688]

[0689] [Synthesis Example 6] Synthesis of Polymer P-6

[0690] Add 6.1 g of monomer a-5, 7.8 g of monomer ALG-2, 4.8 g of 4-hydroxystyrene, 10.6 g of monomer PM-4, and 40 g of THF as a solvent to a 2 L flask. Cool this reaction vessel to -70 °C under a nitrogen atmosphere, and repeat the procedures of vacuum degassing and nitrogen purging three times. After warming up to room temperature, add 1.2 g of AIBN as a polymerization initiator, and heat up to 60 °C to allow the reaction to proceed for 15 hours. Add this reaction solution to 1 L of isopropanol, and filter out the precipitated white solid. Dry the obtained white solid under reduced pressure at 60 °C to obtain polymer P-6. The composition of polymer P-6 was confirmed by 13 C-NMR and 1 H-NMR, and Mw and Mw / Mn were confirmed by GPC.

[0691] [Chemical formula 208]

[0692]

[0693] [Synthesis Example 7] Synthesis of Polymer P-7

[0694] 4.4 g of monomer a-6, 5.9 g of 1-methyl-1-cyclopentyl methacrylate, 4.8 g of 4-hydroxystyrene, 12.2 g of monomer PM-5, and 40 g of THF as a solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under a nitrogen atmosphere, and degassing under reduced pressure and nitrogen purging were repeated three times. After warming to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C to react for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was separated by filtration. The obtained white solid was dried under reduced pressure at 60 °C to obtain polymer P-7. The composition of polymer P-7 was confirmed by 13 C-NMR and 1 H-NMR, and Mw and Mw / Mn were confirmed by GPC.

[0695] [Chemical Formula 209]

[0696]

[0697] [Synthesis Example 8] Synthesis of Polymer P-8

[0698] 3.4 g of monomer a-7, 8.9 g of monomer ALG-1, 4.8 g of 4-hydroxystyrene, 11.0 g of monomer PM-6, and 40 g of THF as a solvent were added to a 2 L flask. The reaction vessel was cooled to -70 °C under a nitrogen atmosphere, and degassing under reduced pressure and nitrogen purging were repeated three times. After warming to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C to react for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was separated by filtration. The obtained white solid was dried under reduced pressure at 60 °C to obtain polymer P-8. The composition of polymer P-8 was confirmed by 13 C-NMR and 1 H-NMR, and Mw and Mw / Mn were confirmed by GPC.

[0699] [Chemical Formula 210]

[0700]

[0701] [Synthesis Example 9] Synthesis of Polymer P-9

[0702] In a 2 L flask, 2.9 g of monomer a-8, 7.1 g of 1-ethynyl-1-cyclopentyl methacrylate, 4.8 g of 3-hydroxystyrene, 11.2 g of monomer PM-7, and 40 g of THF as a solvent were added. The reaction vessel was cooled to -70 °C under a nitrogen atmosphere, and degassing under reduced pressure and nitrogen purging were repeated three times. After warming to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C to allow the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was separated by filtration. The obtained white solid was dried under reduced pressure at 60 °C to obtain polymer P-9. The composition of polymer P-9 was confirmed by 13 C-NMR and 1 H-NMR, and Mw and Mw / Mn were confirmed by GPC.

[0703] [Chemical formula 211]

[0704]

[0705] [Synthesis Example 10] Synthesis of Polymer P-10

[0706] In a 2 L flask, 4.2 g of monomer a-1, 6.2 g of 1-ethynyl-1-cyclopentyl methacrylate, 4.8 g of 3-hydroxystyrene, 10.0 g of monomer PM-8, and 40 g of THF as a solvent were added. The reaction vessel was cooled to -70 °C under a nitrogen atmosphere, and degassing under reduced pressure and nitrogen purging were repeated three times. After warming to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60 °C to allow the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was separated by filtration. The obtained white solid was dried under reduced pressure at 60 °C to obtain polymer P-10. The composition of polymer P-10 was confirmed by 13 C-NMR and 1 H-NMR, and Mw and Mw / Mn were confirmed by GPC.

[0707] [Chemical formula 212]

[0708]

[0709] [Synthesis Example 11] Synthesis of Polymer P-11

[0710] Add 4.2 g of monomer a-1, 7.8 g of monomer ALG-2, 4.8 g of 3-hydroxystyrene, 11.0 g of monomer PM-9, and 40 g of THF as a solvent to a 2 L flask. Cool this reaction vessel to -70 °C under a nitrogen atmosphere, and repeat the vacuum degassing and nitrogen purging 3 times. After warming to room temperature, add 1.2 g of AIBN as a polymerization initiator, and heat to 60 °C to react for 15 hours. Add this reaction solution to 1 L of isopropanol, and filter the precipitated white solid. Dry the obtained white solid under reduced pressure at 60 °C to obtain polymer P-11. The composition of polymer P-11 was determined using 13 C-NMR and 1 H-NMR, and Mw and Mw / Mn were confirmed using GPC.

[0711] [Chemical formula 213]

[0712]

[0713] [Synthesis Example 12] Synthesis of Polymer P-12

[0714] Add 12.5 g of monomer a-1, 6.6 g of 3-hydroxystyrene, and 40 g of THF as a solvent to a 2 L flask. Cool this reaction vessel to -70 °C under a nitrogen atmosphere, and repeat the vacuum degassing and nitrogen purging 3 times. After warming to room temperature, add 1.2 g of AIBN as a polymerization initiator, and heat to 60 °C to react for 15 hours. Add this reaction solution to 1 L of isopropanol, and filter the precipitated white solid. Dry the obtained white solid under reduced pressure at 60 °C to obtain polymer P-12. The composition of polymer P-12 was determined using 13 C-NMR and 1 H-NMR, and Mw and Mw / Mn were confirmed using GPC.

[0715] [Chemical formula 214]

[0716]

[0717] [Synthesis Example 13] Synthesis of Polymer P-13

[0718] Add 4.2 g of monomer a-1, 7.8 g of monomer ALG-2, 4.8 g of 3-hydroxystyrene, 13.8 g of monomer PM-10, and 40 g of THF as a solvent to a 2 L flask. Cool this reaction vessel to -70 °C under a nitrogen atmosphere, and repeat the vacuum degassing and nitrogen purging 3 times. After warming to room temperature, add 1.2 g of AIBN as a polymerization initiator, and heat to 60 °C to react for 15 hours. Add this reaction solution to 1 L of isopropanol, and filter the precipitated white solid. Dry the obtained white solid under reduced pressure at 60 °C to obtain polymer P-13. The composition of polymer P-13 was determined using13 C-NMR and 1 1H-NMR were used for confirmation, and Mw and Mw / Mn were confirmed by GPC.

[0719] [Chemical formula 215]

[0720]

[0721] [Synthesis Example 14] Synthesis of Polymer P-14

[0722] 4.2 g of monomer a-1, 7.8 g of monomer ALG-2, 4.8 g of 3-hydroxystyrene, 11.2 g of monomer PM-11, and 40 g of THF as a solvent were added to a 2 L flask. The reaction vessel was cooled to -70°C under a nitrogen atmosphere, and degassing under reduced pressure and nitrogen purging were repeated 3 times. After warming to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60°C to allow the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was separated by filtration. The obtained white solid was dried under reduced pressure at 60°C to obtain Polymer P-14. The composition of Polymer P-14 was confirmed by 13 C-NMR and 1 1H-NMR, and Mw and Mw / Mn were confirmed by GPC.

[0723] [Chemical formula 216]

[0724]

[0725] [Synthesis Example 15] Synthesis of Polymer P-15

[0726] 4.2 g of monomer a-1, 7.8 g of monomer ALG-2, 4.8 g of 3-hydroxystyrene, 10.2 g of monomer PM-12, and 40 g of THF as a solvent were added to a 2 L flask. The reaction vessel was cooled to -70°C under a nitrogen atmosphere, and degassing under reduced pressure and nitrogen purging were repeated 3 times. After warming to room temperature, 1.2 g of AIBN as a polymerization initiator was added, and the temperature was raised to 60°C to allow the reaction to proceed for 15 hours. The reaction solution was added to 1 L of isopropanol, and the precipitated white solid was separated by filtration. The obtained white solid was dried under reduced pressure at 60°C to obtain Polymer P-15. The composition of Polymer P-15 was confirmed by 13 C-NMR and 1 1H-NMR, and Mw and Mw / Mn were confirmed by GPC.

[0727] [Chemical formula 217]

[0728]

[0729] [Comparative Synthesis Example 1] Synthesis of Comparative Polymer cP-1

[0730] Comparative polymer cP-1 was obtained in the same manner as in Synthesis Example 1 except that monomer a-1 was not used. The composition of comparative polymer cP-1 was determined using 13 C-NMR and 1 H-NMR, and Mw and Mw / Mn were determined using GPC.

[0731] [Chemical formula 218]

[0732]

[0733] [Examples 1 to 15, Comparative Example 1]

[0734] Each component was dissolved in a solvent containing 50 ppm of surfactant PolyFox PF-636 manufactured by Omnova Solutions as a surfactant according to the composition shown in Table 1, and the resulting solution was filtered through a 0.2 μm filter to prepare a positive resist material.

[0735] In Table 1, each component is as follows.

[0736] · Organic solvent: PGMEA (propylene glycol monomethyl ether acetate)

[0737] DAA (diacetone alcohol)

[0738] EL (ethyl lactate)

[0739] · Acid generator: PAG-1, PAG-2

[0740] [Chemical formula 219]

[0741]

[0742] · Quencher: Q-1

[0743] [Chemical formula 220]

[0744]

[0745] (2) EUV lithography evaluation

[0746] Each positive resist material shown in Table 1 was spin-coated on a Si substrate on which Shin-Etsu Chemical Co., Ltd.'s spin-on hard mask SHB-A940 (silicon content: 43 mass%) was formed with a film thickness of 20 nm, and pre-baked on a hot plate at 105 °C for 60 seconds to fabricate a positive resist film with a film thickness of 40 nm. Using an EUV scanning exposure machine NXE3400 (NA 0.33, σ 0.9 / 0.7, dipole illumination) manufactured by ASML, the aforementioned resist film was exposed, PEB was performed on a hot plate at the temperature described in Table 1 for 60 seconds, and development was carried out for 30 seconds with a 2.38 mass% TMAH aqueous solution to form lines and spaces with a pitch of 32 nm and a line width of 16 nm.

[0747] Using a length-measuring SEM (CG6300) manufactured by Hitachi High-Technologies Corporation, the exposure dose at which line patterns were formed with a size of 16 nm ± 1.6 nm was determined, and the line edge roughness (LWR) of the lines at this exposure dose was measured. The wafer was diced, and a 16-nm line was observed with an SEM (S-4800) manufactured by Hitachi High-Technologies Corporation, and the spacing portion was also observed for any trailing. The results are shown in Table 1.

[0748] [Table 1]

[0749]

[0750] From the results shown in Table 1, it can be seen that the positive resist material of the present invention containing the polymer having the repeating unit a represented by formula (a) has sufficient sensitivity and meets the reduction effects of LWR and trailing in the spacing portion.

Claims

1. A positive resist material comprising a base polymer containing a repeating unit a represented by the following formula (a), In the formula, m is 0 or 1; n is an integer from 0 to 4; R A is a hydrogen atom or a methyl group; X 1 is a single bond or an ester bond; X 2 It is a single bond, a saturated alkylene group having 1 to 10 carbon atoms, a phenylene group or a naphthylene group; X 3 is a single bond, an ester bond, an ether bond or a carbonyl group; R 1 is a hydrocarbon group having 1 to 8 carbon atoms, a hydroxyl group, a hydrocarbonoxy group having 1 to 8 carbon atoms, a hydrocarboncarbonyloxy group having 2 to 8 carbon atoms, a hydrocarbonoxycarbonyloxy group having 2 to 8 carbon atoms, or a halogen atom; R 2 and R 3 are each independently a single bond, methylene, ethylene, propylene or butylene, and may be substituted by a halogen atom; but R 2 and R 3 Not single bond at the same time; Ring R is a benzene ring or a naphthalene ring, and may be substituted by a hydrocarbon group having 1 to 8 carbon atoms, a hydroxyl group, a hydrocarbonoxy group having 1 to 8 carbon atoms, a hydrocarboncarbonyloxy group having 2 to 8 carbon atoms, a hydrocarbonoxycarbonyloxy group having 2 to 8 carbon atoms, or a halogen atom; *1 and *2 represent atomic bonds of carbon atoms on the aromatic ring in the formula.

2. The positive resist material according to claim 1, wherein The base polymer further contains a repeating unit b in which the hydrogen atom of the carboxyl group or the phenolic hydroxyl group is substituted with an acid-labile group.

3. The positive resist material according to claim 2, wherein The repeating unit b is at least one selected from the repeating unit b1 represented by the following formula (b1) and the repeating unit b2 represented by the following formula (b2), In the formula, R A are each independently a hydrogen atom or a methyl group; Y 1 is a single bond, a 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 nitro group, a hydroxyl group, a saturated hydrocarbonoxy group having 1 to 8 carbon atoms, a saturated hydrocarboncarbonyloxy group having 2 to 8 carbon atoms, and a saturated hydrocarbonoxycarbonyloxy group having 2 to 8 carbon atoms; Y 2 is a single bond, an ester bond or an amide bond; Y 3 is a single bond, an ether bond or an ester bond; R 11 and R 12 It is an acid-labile group; R 13 is a fluorine atom, a trifluoromethyl group, a cyano group, or an alkyl 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; but 1≤a+b≤5.

4. The positive resist material according to claim 1, wherein The base polymer further contains a repeating unit c having an adhesive group selected from a hydroxyl group, a carboxyl group, a lactone ring, a carbonate group, a thiocarbonate group, a carbonyl group, a cyclic acetal group, an ether bond, an ester bond, a sulfonate bond, a cyano group, an amide group, -OC(=O)-S- and -OC(=O)-NH-. The positive resist material according to claim 1 , further comprising an organic solvent. The positive resist material according to claim 1 , further comprising an acid generator. The positive resist material according to claim 1 , further comprising a quencher. The positive resist material according to claim 1 , further comprising a surfactant.

9. A pattern forming method comprising the following steps: forming a resist film on a substrate using the positive resist material according to any one of claims 1 to 8, exposing the resist film to high energy radiation, and The exposed resist film is developed using a developer.

10. The pattern forming method according to claim 9, wherein: The high-energy ray is i-ray, KrF excimer laser, ArF excimer laser, electron beam or extreme ultraviolet ray with a wavelength of 3 to 15 nm.

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