Nonionic photoacid generator and resin composition for photolithography

Abstract

The purpose of the present invention is to provide: a photoacid generator containing a sulfonamide compound which has a high decomposition rate in response to near-ultraviolet rays, generates a superacid bis-sulfonamide, and is highly soluble in a resist solvent; and a photolithography resin composition which contains the photoacid generator and is highly sensitive to near-ultraviolet rays. The present invention pertains to: a nonionic photoacid generator (A) characterized by containing a sulfonamide compound represented by general formula (1); and a photolithography resin composition (Q) containing the nonionic photoacid generator (A).

Description

Technical Field

[0001] The present invention relates to a nonionic photoacid generator and a resin composition for photolithography. More specifically, the present invention relates to a nonionic photoacid generator containing a sulfonamide compound suitable for generating a super strong acid by the action of ultraviolet light (i-line, KrF line), and a resin composition for photolithography containing the nonionic photoacid generator.

[0002] Conventionally, in the field of microfabrication typified by semiconductor manufacturing, a photolithography process of transferring a desired pattern onto a resist using light of various wavelengths has been widely used. As a resist material, for example, a resin composition containing a polymer having a tert-butyl ester of carboxylic acid or a tert-butyl carbonate of phenol and a photoacid generator is used. A solution of this resist material dissolved in a solvent is applied onto a substrate and irradiated with light, whereby the photoacid generator decomposes to generate a super strong acid such as trifluoromethanesulfonic acid (an acid having an acidity higher than that of 100% sulfuric acid). Further, by performing post-exposure baking (PEB), acid-reactive groups such as tert-butyl ester groups or tert-butyl carbonate groups in the polymer are dissociated by the generated acid, and carboxylic acids or phenolic hydroxyl groups are formed, and the light-irradiated portion becomes easily soluble in an alkaline developer. Since pattern formation is performed using this phenomenon, the development of a highly sensitive resist material capable of obtaining a desired pattern with a small exposure amount has been eagerly desired for energy saving and shortening of the process time. Therefore, as a photoacid generator for realizing a highly sensitive resist material, it is desirable that the photoacid generator has a high photodecomposition rate and the generated acid has a higher acid strength.

[0003] For the above reasons, ionic photoacid generators such as triarylsulfonium salts (Patent Document 1) and phenacylsulfonium salts having a naphthalene skeleton (Patent Document 2), and nonionic photoacid generators having an oxime sulfonate structure (Patent Document 3) or a naphthalimide structure (Patent Documents 4 and 5) have been disclosed as photoacid generators preferable for the photolithography process.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Summary of the Invention

Problems to be Solved by the Invention

[0005] As a light source for a photolithography process that decomposes a photoacid generator in a photoresist resin composition, near-ultraviolet rays such as i-line (365 nm) and KrF-line (248 nm) are widely used due to their availability and stability. As the semiconductor market grows, the demand for developing photoacid generators with high sensitivity to these near-ultraviolet rays is increasing. Also, in the current situation where the photolithography process is diversifying, it is required that the resist solvent contained in the photoresist resin composition has high solubility so that there is no solid precipitation or phase separation even in a high-concentration photoresist resin composition.

[0006] However, ionic photoacid generators such as triarylsulfonium salts and phenacylsulfonium salts have a low photodecomposition rate with respect to the i-line and are low in sensitivity. Furthermore, since they are salts, there is a problem that phase separation or precipitation occurs when they are contained in a high concentration in the photoresist resin composition.

[0007] Nonionic photoacid generators having an oxime sulfonate structure and a naphthalimide structure have a high photodegradation rate with respect to i-line, but in practical use, the generated acid is limited to sulfonic acid, and there has been a problem that sufficient acidity cannot be obtained and the sensitivity is low.

[0008] That is, an object of the present invention is to provide a photoacid generator containing a sulfonamide compound that generates bis-sulfonamide, which is a super strong acid with a high decomposition rate with respect to near-ultraviolet rays such as i-line and KrF-line, and is highly soluble in a resist solvent, and a resin composition for photolithography containing the same and having high sensitivity to near-ultraviolet rays.

Means for Solving the Problems

[0009] As a result of intensive studies to achieve the above object, the present inventors have reached the present invention. That is, the present invention is a nonionic photoacid generator (A) characterized by containing a sulfonamide compound represented by the following general formula (1); and a resin composition (Q) for photolithography containing the nonionic photoacid generator (A).

[0010]

Chemical formula

[0011] [In the formula, R f is a fluorine atom, a fluoroalkyl group, or a fluoroaryl group, R 1 is a fluorine atom, an alkyl group, a fluoroalkyl group, an aryl group, or a fluoroaryl group, R f and R 1 may be bonded to each other to form a ring, R 2 is a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a heteroatom-containing aryl group, an alkylcarbonyl group, an arylcarbonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, or an arylsulfonyl group, R 3 is a cyclic alkyl group, an aryl group, or a heteroatom-containing aryl group, R 2 and R 3may be combined with each other to form a ring (which may contain a heteroatom).

Advantages of the Invention

[0012] The nonionic photoacid generator (A) of the present invention generates a super strong acid with a high decomposition rate against near ultraviolet rays and has excellent solubility in a resist solvent. Further, the photolithography resin composition (Q) containing the same is highly sensitive to near ultraviolet rays.

Modes for Carrying Out the Invention

[0013] The sulfonamide compound contained in the nonionic photoacid generator (A) of the present invention is represented by the following general formula (1).

[0014]

Chemical Formula

[0015] [In the formula, R f is a fluorine atom, a fluoroalkyl group, or a fluoroaryl group, and R 1 is a fluorine atom, an alkyl group, a fluoroalkyl group, an aryl group, or a fluoroaryl group, and R f and R 1 may be combined with each other to form a ring, and R 2 is a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a heteroatom-containing aryl group, an alkylcarbonyl group, an arylcarbonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, or an arylsulfonyl group, and R 3 is a cyclic alkyl group, an aryl group, or a heteroatom-containing aryl group, and R 2 and R 3 may be combined with each other to form a ring (which may contain a heteroatom).

[0016] In the general formula (1), R f is a fluorine atom, a fluoroalkyl group, or a fluoroaryl group, and may have a substituent. R f is R1 It may combine to form a ring.

[0017] A fluoroalkyl group is an alkyl group in which at least one hydrogen is substituted by fluorine, and examples thereof include fluoroalkyl groups having 1 to 10 carbon atoms (excluding substituents; the same applies hereinafter unless otherwise specified), such as a linear fluoroalkyl group (RF1), a branched fluoroalkyl group (RF2), or a cyclic fluoroalkyl group (RF3).

[0018] Examples of the linear fluoroalkyl group (RF1) include a trifluoromethyl group, a pentafluoroethyl group, a heptafluoropropyl group, a nonafluorobutyl group, a perfluorohexyl group, a perfluorooctyl group, a perfluorodecanyl group, a difluoromethyl group, a 1,1,2,2,3,3,4,4,5,5,6,6-dodecafluorohexyl group, a difluoro(methoxycarbonyl)methyl group, and a 2-adamantylcarbonyloxy-1,1-difluoroethyl group.

[0019] Examples of the branched fluoroalkyl group (RF2) include a hexafluoroisopropyl group, a nonafluoro-tert-butyl group, and a perfluoro-2-ethylhexyl group.

[0020] Examples of the cyclic fluoroalkyl group (RF3) include a heptafluorocyclobutyl group, a nonafluorocyclopentyl group, a perfluorocyclohexyl group, and a perfluoro(1-cyclohexyl)methyl group.

[0021] A fluoroaryl group is an aryl group in which at least one hydrogen is substituted by fluorine, and examples thereof include fluoroaryl groups having 6 to 10 carbon atoms (RF4).

[0022] Examples of the fluoroaryl group (RF4) having 6 to 10 carbon atoms include a 3,4,5-trifluorophenyl group, a pentafluorophenyl group, a perfluoronaphthyl group, a 3-trifluoromethyltetrafluorophenyl group, and a 3,5-bistrifluoromethylphenyl group.

[0023] R f Among them, from the viewpoints of the deprotection ability of the photoresist and the availability of raw materials, a linear fluoroalkyl group (RF1), a branched fluoroalkyl group (RF2), and a fluoroaryl group (RF4) are preferred, a linear fluoroalkyl group (RF1) and a fluoroaryl group (RF4) are more preferred, and a trifluoromethyl group (CF 3 ), a pentafluoroethyl group (C 2 F 5 ), a heptafluoropropyl group (C 3 F 7 ), a nonafluorobutyl group (C 4 F 9 ), and a pentafluorophenyl group (C 6 F 5 ) are particularly preferred.

[0024] In the general formula (1), R 1 is a fluorine atom, an alkyl group, a fluoroalkyl group, an aryl group, or a fluoroaryl group, and may have a substituent.

[0025] Examples of the alkyl group include a linear alkyl group (RA1) having 1 to 18 carbon atoms, a branched alkyl group (RA2) having 1 to 18 carbon atoms, and a cyclic alkyl group (RA3) having 3 to 18 carbon atoms.

[0026] Examples of the linear alkyl group (RA1) include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, an octyl group, a decyl group, a dodecyl group, a tetradecyl group, a hexadecyl group, an octadecyl group, a benzyl group, a benzyloxymethyl group, a methoxymethyl group, an ethoxymethyl group, a 2-methoxyethyl group, a 1-methoxyethyl group, a trimethylsilyloxymethyl group, a triethylsilyloxymethyl group, and a tert-butyldimethylsilyloxymethyl group.

[0027] Examples of the branched alkyl group (RA2) include an isopropyl group, isobutyl group, sec-butyl group, tert-butyl group, isopentyl group, neopentyl group, tert-pentyl group, isohexyl group, 1-methylbutyl group, 2-ethylhexyl group, 2-hexyldecyl group, isodecyl group, isooctadecyl group, and the like.

[0028] Examples of the cyclic alkyl group (RA3) include a cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, norbornyl group, 1-adamantyl group, 2-adamantyl group, menthyl group, 10-camphyl group, octahydronaphthyl group, tricyclodecanyl group, tetracyclododecanyl group, 4-dodecylcyclohexyl group, and the like.

[0029] Examples of the fluoroalkyl group include those similar to the above linear fluoroalkyl group (RF1), branched fluoroalkyl group (RF2), or cyclic fluoroalkyl group (RF3).

[0030] Examples of the aryl group include aryl groups (RA4) having 6 to 10 carbon atoms, such as a phenyl group, 1-naphthyl group, 2-naphthyl group, 1-azulenyl group, 2-tolyl group, 3-tolyl group, 4-tolyl group, 2-chlorophenyl group, 3-chlorophenyl group, 4-chlorophenyl group, 2-nitrophenyl group, 4-nitrophenyl group, 2,4-xylyl group, 2,6-xylyl group, 3,5-xylyl group, 2,4-dinitrophenyl group, 2,4,6-mesityl group, and the like.

[0031] Examples of the fluoroaryl group include those similar to the above fluoroaryl group (RF4).

[0032] Among these, from the viewpoint of availability of raw materials, a linear alkyl group having 1 to 12 carbon atoms, a cyclic alkyl group having 3 to 12 carbon atoms, a linear fluoroalkyl group (RF1) having 1 to 10 carbon atoms, an aryl group having 6 to 8 carbon atoms, and a fluoroaryl group having 6 to 8 carbon atoms are preferable, and more preferably a methyl group, ethyl group, propyl group, butyl group, octyl group, 10-camphyl group, trifluoromethyl group (CF3 ) a pentafluoroethyl group (C 2 F 5 ) a heptafluoropropyl group (C 3 F 7 ) a nonafluorobutyl group (C 4 F 9 ) a phenyl group, a 4-tolyl group, a 2-nitrophenyl group, a 4-nitrophenyl group, a 2,4-dinitrophenyl group and a pentafluorophenyl group (C 6 F 5 ) and particularly preferably a trifluoromethyl group (CF 3 ) a pentafluoroethyl group (C 2 F 5 ) a heptafluoropropyl group (C 3 F 7 ) a nonafluorobutyl group (C 4 F 9 ) and a pentafluorophenyl group (C 6 F 5 ).

[0033] In the general formula (1), R 2 is a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a heteroatom-containing aryl group, an alkylcarbonyl group, an arylcarbonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, or an arylsulfonyl group, and may have a substituent. R 2 may combine with R 3 to form a ring (which may contain a heteroatom).

[0034] Examples of the alkyl group include the same ones as the above-mentioned linear alkyl group (RA1), branched alkyl group (RA2) and cyclic alkyl group (RA3).

[0035] Examples of the alkenyl group include alkenyl groups having 2 to 10 carbon atoms (RE1), etc., and linear, branched, or cyclic alkenyl groups (ethenyl, cyanoethenyl, dicyanoethenyl, phenylethenyl, 1-propenyl, 2-propenyl, 1-buten-1-yl, 2-buten-1-yl, 2-methyl-2-propenyl, 1-cyclopenten-1-yl, 1-cyclohexen-1-yl, 1-decen-1-yl, norbornenyl, etc.) etc. are included.

[0036] Examples of the alkynyl group include alkynyl groups having 2 to 10 carbon atoms (RY1), etc., and linear, branched, or cyclic alkynyl groups (ethynyl, 1-propyn-1-yl, 2-propyn-1-yl, 1-butyn-1-yl, 2-butyn-1-yl, 3-butyn-1-yl, 1-pentyn-1-yl, 2-pentyn-1-yl, 3-pentyn-1-yl, 4-pentyn-1-yl, 1-hexyn-1-yl, 3-methyl-1-butyn-1-yl, 1-methyl-2-butyn-1-yl, 1-methyl-3-butyn-1-yl, 1,1-dimethyl-2-propyn-1-yl, 1-cyclooctyn-1-yl, 2-phenylethyn-1-yl, etc.) etc. are included.

[0037] Examples of the aryl group include aryl groups having 6 to 14 carbon atoms (RA5), etc., and phenyl group, 4-cyanophenyl group, 1-naphthyl group, 2-naphthyl group, 1-anthracenyl group, 2-anthracenyl group, 9-anthracenyl group, 3-phenanthrenyl, 9-phenanthrenyl, 1-azulenyl group, 2-fluorenyl group, 9’,9’-dimethyl-2-fluorenyl group, 9’,9’-bis(trifluoromethyl)-2-fluorenyl group, etc. are included.

[0038] Examples of the heteroatom-containing aryl group include heteroatom-containing aryl groups (RA6) having 3 to 14 carbon atoms, such as a furanyl group, a thienyl group, a pyrrolyl group, an oxazolyl group, a thiazolyl group, a thiophenyl group, a benzofuranyl group, an isobenzofuranyl group, a benzopyranyl group, a benzothiazolyl group, a benzimidazolyl group, an indolyl group, an indoleninyl group, a naphthothiazolyl group, a naphthoxazolyl group, a xanthenyl group, a thioxanthenyl group, a phenoxathiinyl group, a dibenzo-p-dioxinyl group, a thianthrenyl group, a xanthonyl group, a thioxanthonyl group, an anthraquinonyl group, a dibenzofuranyl group, a fluorenyl group, a carbazolyl group, and a coumarinyl group, which contain one or more heteroatoms selected from the group consisting of oxygen, nitrogen, and sulfur.

[0039] Examples of the alkylcarbonyl group include alkylcarbonyl groups (RC1) having 1 to 10 carbon atoms (excluding the carbonyl carbon), such as linear or branched alkylcarbonyl groups (acetyl, propionyl, butanoyl, 2-methylpropionyl, pentanoyl, 2-methylbutanoyl, 3-methylbutanoyl, 2,2-dimethylpropanoyl, octanoyl, 2-ethylhexanoyl, and decanoyl, etc.).

[0040] Examples of the arylcarbonyl group include arylcarbonyl groups (RC2) having 6 to 10 carbon atoms (excluding the carbonyl carbon), such as a benzoyl group, a naphthoyl group, and a 4-toluoyl group, etc.

[0041] Examples of the alkoxycarbonyl group include alkoxycarbonyl groups (RC3) having 1 to 10 carbon atoms (excluding the carbonyl carbon), such as linear or branched alkoxycarbonyl groups (methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl, butoxycarbonyl, isobutoxycarbonyl, sec-butoxycarbonyl, tert-butoxycarbonyl, tert-amyloxycarbonyl, octyloxycarbonyl, 2-ethylhexyloxycarbonyl, and benzyloxycarbonyl (Cbz), etc.).

[0042] Examples of the aryloxycarbonyl group include aryloxycarbonyl groups having 6 to 10 carbon atoms (excluding the carbon atom on the carbonyl group) (RC4), such as a phenoxycarbonyl group, 2-tolyloxycarbonyl group, 4-tolyloxycarbonyl group, 4-methoxyphenoxycarbonyl group, 4-chlorophenoxycarbonyl group, 1-naphthoxycarbonyl group, 2-naphthoxycarbonyl group, and the like.

[0043] Examples of the alkylsulfonyl group include alkylsulfonyl groups having 1 to 10 carbon atoms (RC5), such as linear or branched alkylsulfonyl groups (methylsulfonyl, ethylsulfonyl, propylsulfonyl, isopropylsulfonyl, butylsulfonyl, isobutylsulfonyl, sec-butylsulfonyl, tert-butylsulfonyl, pentylsulfonyl, isopentylsulfonyl, neopentylsulfonyl, tert-pentylsulfonyl, octylsulfonyl, decylsulfonyl, trifluoromethanesulfonyl, pentafluoroethanesulfonyl, nonafluorobutanesulfonyl, perfluorooctanesulfonyl, etc.).

[0044] Examples of the arylsulfonyl group include arylsulfonyl groups having 6 to 10 carbon atoms (RC6) (benzenesulfonyl, 2-toluenesulfonyl, 4-toluenesulfonyl, 2-nitrobenzenesulfonyl, 4-nitrobenzenesulfonyl, 2,4-dinitrobenzenesulfonyl, 2-mesitylenesulfonyl, 4-butylbenzenesulfonyl, 4-tert-butylbenzenesulfonyl, naphthylsulfonyl, pentafluorobenzenesulfonyl, 3,5-bis(trifluoromethyl)benzenesulfonyl, etc.).

[0045] In the general formula (1), R 3 is a cyclic alkyl group, an aryl group or a heteroatom-containing aryl group, and may have a substituent.

[0046] Examples of the cyclic alkyl group include cyclic alkyl groups (RA7) having 3 to 12 carbon atoms, such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, norbornyl group, 1-adamantyl group, 2-adamantyl group, menthyl group, 10-camphyl group, octahydronaphthyl group, tricyclodecanyl group, tetracyclododecanyl group, and 4-hexylcyclohexyl group.

[0047] Examples of the aryl group include the same ones as the above aryl group (RA5).

[0048] Examples of the heteroatom-containing aryl group include the same ones as the above heteroatom-containing aryl group (RA6).

[0049] Examples of the substituents of the above aryl group (RA5) and heteroatom-containing aryl group (RA6) include the same ones as those listed in (R 6 ) described later.

[0050] In general formula (1), R 3 is bonded to R 2 at an appropriate position on the carbon of the above cyclic alkyl group (RA7), aryl group (RA5), and heteroatom-containing aryl group (RA6) to form a cyclic structure, and may contain a heteroatom.

[0051] In general formula (1), among the aforementioned R 2 and R 3 , from the viewpoints of availability of raw materials, ease of synthesis, and stability, preferably the following (a) and (b) are included.

[0052] (a): In general formula (1), R 2 is an alkyl group having 1 to 18 carbon atoms, an aryl group having 6 to 14 carbon atoms, or a heteroatom-containing aryl group having 3 to 14 carbon atoms, and R 3 is a cyclic alkyl group having 3 to 12 carbon atoms, an aryl group having 6 to 14 carbon atoms, or a heteroatom-containing aryl group having 3 to 14 carbon atoms, and R 2 and R 3They are bonded to each other to form a 5- to 7-membered ring (which may contain a heteroatom). Preferably, the following general formulas (1)-1, (1)-2, and (2)-1 to (2)-5 are mentioned. More preferably, they are general formulas (1)-1 and (2)-1 to (2)-5. In general formula (1)-2, a plurality of R 1 are independent of each other.

[0053]

Chemical formula

[0054]

Chemical formula

[0055] (b): In general formula (1), R 2 is an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 14 carbon atoms, a heteroatom-containing aryl group having 3 to 14 carbon atoms, an arylcarbonyl group having 6 to 10 carbon atoms (excluding the carbonyl carbon), an alkoxycarbonyl group having 1 to 10 carbon atoms (excluding the carbonyl carbon), or an alkylsulfonyl group having 1 to 10 carbon atoms, and R 3 is a cyclic alkyl group having 3 to 12 carbon atoms, an aryl group having 6 to 14 carbon atoms, or a heteroatom-containing aryl group having 3 to 14 carbon atoms. Preferably, the following general formulas (3)-1 to (3)-4, (4)-1, and (4)-2 are mentioned. More preferably, they are general formulas (3)-1, (3)-2, (3)-4, (4)-1, and (4)-2. Note that R 2 is a group selected from the above groups.

[0056]

Chemical formula

[0057]

Chemical formula

[0058] In the general formula (1)-1, G 1 is a group in which R 2 and R 3 are combined to form a ring, and examples thereof include -CH 2 -, -CH 2 -CH 2 -, -O-, -S-, or -NR 7 - etc. R 7 is an alkyl group having 1 to 4 carbon atoms, a phenyl group, an acetyl group, a propionyl group, a butanoyl group, a benzoyl group, a mesyl group, a benzenesulfonyl group, a tosyl group, or a nosyl group. From the viewpoints of availability of raw materials and ease of synthesis, it is preferably an alkyl group having 1 to 4 carbon atoms, a phenyl group, an acetyl group, or a benzoyl group, and more preferably a methyl group or a phenyl group.

[0059] In the general formulas (2)-1 to (2)-5, G 2 is a group in which R 2 and R 3 are combined to form a ring, and examples thereof include -CH 2 -, -O-, -S-, or -NR 8 - etc. (R 8 is the same as the above R 7 ), and R 8 is preferably an alkyl group having 1 to 4 carbon atoms, a phenyl group, an acetyl group, or a benzoyl group from the viewpoints of availability of raw materials and ease of synthesis.

[0060] In the general formulas (2)-1 to (2)-5, R 4 and R 5 are a hydrogen atom or a substituent of a ring formed by the combination of R 2 and R 3 respectively, and independently include a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, an aryl group having 6 to 14 carbon atoms (RA5), a halogen atom, etc. From the viewpoint of ease of synthesis, they are preferably a hydrogen atom, a linear alkyl group having 1 to 6 carbon atoms, a phenyl group, or a halogen atom.

[0061] Examples of the above halogen atom include the same ones as those listed in (R 6 ) described later.

[0062] In general formula (3)-4, G 3 and G 4 are groups that form a condensed ring. When representing their combination as (G 3 , G 4 ), examples include (-O-, -O-), (-S-, -S-), (-C(O)-, -O-), (-C(O)-, -S-), (-C(O)-, -C(O)-), (-CH=CH-, single bond), (-O-, single bond), (-S-, single bond), (-CH 2 -, single bond) or (-C(O)-, single bond), etc.

[0063] In general formulas (4)-1 and (4)-2, G 5 is -CMe 2 -, -O-, -S-, or -NR 9 - (Me represents a methyl group, and R 9 is the same as the above R 7 ), and R 9 is preferably an alkyl group having 1 to 4 carbon atoms, a phenyl group, an acetyl group, or a benzoyl group, more preferably a methyl group, from the viewpoints of availability of raw materials and ease of synthesis.

[0064] In the above general formula, (R 6 ) n are n independent substituents (n is an integer from 0 to 8) at any positions on the above aryl group (RA5) or heteroatom-containing aryl group (RA6), and may be bonded to each other to form a ring, and examples include an alkyl group, a fluoroalkyl group, an alkenyl group, an alkynyl group, an aryl group, a heteroatom-containing aryl group, an alkoxy group, an alkylthio group, an alkylcarbonyl group, an arylcarbonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkylcarbonyloxy group, an arylcarbonyloxy group, an alkyl carbonate group, an aryl carbonate group, an alkylsulfonyl group, an arylsulfonyl group, an amino group, and a halogen atom, etc.

[0065] In general formulas (1)-1, (1)-2, and (2)-1 to (2)-5, the substitution positions of (R 6 ) in general formula (1) are R 2 and R3 is combined and the formed structure is regarded as the mother skeleton and determined. In general formulas (3)-1 to (3)-4, (4)-1 and (4)-2, the substitution position of (R 6 ) is determined by regarding R 3 in general formula (1) as the mother skeleton.

[0066] Examples of the alkyl group of (R 6 ) include those similar to the above linear alkyl group (RA1), branched alkyl group (RA2), and cyclic alkyl group (RA3). From the viewpoints of availability of raw materials and ease of synthesis, it is preferably a linear, branched, or cyclic alkyl group having 1 to 8 carbon atoms, more preferably a methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, hexyl group, 2-ethylhexyl group, cyclopentyl group, and cyclohexyl group.

[0067] Examples of the fluoroalkyl group of (R 6 ) include those similar to the above linear fluoroalkyl group (RF1), branched fluoroalkyl group (RF2), and cyclic fluoroalkyl group (RF3). From the viewpoints of availability of raw materials and ease of synthesis, it is preferably a linear, branched, or cyclic fluoroalkyl group having 1 to 8 carbon atoms, more preferably a trifluoromethyl group, pentafluoroethyl group, heptafluoropropyl group, nonafluorobutyl group, and hexafluoroisopropyl group.

[0068] Examples of the alkenyl group of (R 6 ) include those similar to the above alkenyl group (RE1).

[0069] Examples of the alkynyl group of (R 6 ) include those similar to the above alkynyl group (RY1). From the viewpoint of ease of synthesis, a 1-propyn-1-yl group, 1-butyn-1-yl group, 1-pentyn-1-yl group, and 2-phenylethyn-1-yl group are preferred.

[0070] (R 6Examples of the aryl group in (R

[0071] (R 6 ) include the same groups as the above-mentioned heteroatom-containing aryl group (RA6).

[0072] (R 6 ) Examples of the alkoxy group include alkoxy groups having 1 to 10 carbon atoms (RC7), etc., and linear, branched or cyclic alkoxy groups (methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, sec-butoxy, tert-butoxy, hexyloxy, cyclohexyloxy, phenoxy, tolyloxy, benzyloxy, decyloxy, naphthoxy, methoxymethoxy, ethoxymethoxy, 2-methoxyethoxy, 1-methoxyethoxy, benzyloxymethoxy, trimethylsiloxy, triethylsiloxy, triisopropylsiloxy and tert-butyldimethylsiloxy, etc.), etc. From the viewpoint of ease of synthesis, methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, tert-butoxy, pentyloxy, hexyloxy, benzyloxy and tert-butyldimethylsiloxy are preferred.

[0073] (R 6 ) Examples of the alkylthio group include alkylthio groups having 1 to 10 carbon atoms (RC8), etc., and linear, branched or cyclic alkylthio groups (methylthio, ethylthio, propylthio, isopropylthio, butylthio, isobutylthio, sec-butylthio, tert-butylthio, pentylthio, isopentylthio, neopentylthio, tert-pentylthio, phenylthio, tolylthio, benzylthio, octylthio, decylthio and naphthylthio, etc.), etc. From the viewpoint of ease of synthesis, methylthio, ethylthio, propylthio, isopropylthio, butylthio, benzylthio, octylthio and phenylthio are preferred.

[0074] (R 6) As the alkylcarbonyl group, those similar to the above alkylcarbonyl group (RC1) can be mentioned, and from the viewpoint of ease of synthesis, acetyl, propionyl, butanoyl, 2-methylbutanoyl, and 2,2-dimethylpropanoyl are preferable.

[0075] (R 6 ) As the arylcarbonyl group, those similar to the above arylcarbonyl group (RC2) can be mentioned.

[0076] (R 6 ) As the alkoxycarbonyl group, those similar to the above alkoxycarbonyl group (RC3) can be mentioned, and from the viewpoint of ease of synthesis, methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl, butoxycarbonyl, sec-butoxycarbonyl, tert-butoxycarbonyl, tert-amyloxycarbonyl, and 2-ethylhexyloxycarbonyl are preferable.

[0077] (R 6 ) As the aryloxycarbonyl group, those similar to the above aryloxycarbonyl group (RC4) can be mentioned.

[0078] (R 6) Examples of the alkylcarbonyloxy group include an alkylcarbonyloxy group having 1 to 10 carbon atoms (excluding the carbonyl carbon) (RC9), etc., and linear or branched alkylcarbonyloxy groups (such as acetoxy, ethylcarbonyloxy, propylcarbonyloxy, isopropylcarbonyloxy, butylcarbonyloxy, isobutylcarbonyloxy, sec-butylcarbonyloxy, tert-butylcarbonyloxy, pentylcarbonyloxy, hexylcarbonyloxy, octylcarbonyloxy, 2-ethylhexylcarbonyloxy, decylcarbonyloxy, and benzylcarbonyloxy, etc.). From the viewpoint of availability of raw materials, acetoxy, ethylcarbonyloxy, propylcarbonyloxy, isopropylcarbonyloxy, butylcarbonyloxy, isobutylcarbonyloxy, sec-butylcarbonyloxy, tert-butylcarbonyloxy, pentylcarbonyloxy, hexylcarbonyloxy, and 2-ethylhexylcarbonyloxy are preferred.

[0079] (R 6 ) Examples of the arylcarbonyloxy group include an arylcarbonyloxy group having 6 to 10 carbon atoms (excluding the carbonyl carbon) (RC10), etc., and a phenylcarbonyloxy group, 1-naphthylcarbonyloxy group, 2-naphthylcarbonyloxy group, 1-azulenylcarbonyloxy group, 2-tolylcarbonyloxy group, 3-tolylcarbonyloxy group, 4-tolylcarbonyloxy group, 2-chlorophenylcarbonyloxy group, 3-chlorophenylcarbonyloxy group, 4-chlorophenylcarbonyloxy group, 2,4-xylylcarbonyloxy group, 2,6-xylylcarbonyloxy group, 3,5-xylylcarbonyloxy group, 2,4,6-mesitylcarbonyloxy group, 3,5-bistrifluoromethylphenylcarbonyloxy group, and pentafluorophenylcarbonyloxy group, etc.

[0080] (R 6) As for the alkyl carbonate group, examples thereof include an alkyl carbonate group (RC11) having 1 to 10 carbon atoms (excluding the carbonyl carbon), etc., such as a methyl carbonate group, an ethyl carbonate group, a propyl carbonate group, a 2-propyl carbonate group, a butyl carbonate group, a 2-butyl carbonate group, an isobutyl carbonate group, a tert-butyl carbonate group, a tert-amyl carbonate group, a benzyl carbonate group, a 2-ethylhexyl carbonate group, and a menthyl carbonate group, etc. From the viewpoint of availability of raw materials, preferably, they are a methyl carbonate group, an ethyl carbonate group, a propyl carbonate group, an isopropyl carbonate group, a butyl carbonate group, an isobutyl carbonate group, a tert-butyl carbonate group, a tert-amyl carbonate group, and a 2-ethylhexyl carbonate group.

[0081] (R 6 ) As for the aryl carbonate group, examples thereof include an aryl carbonate group (RC12) having 6 to 10 carbon atoms (excluding the carbonyl carbon), etc., such as a phenyl carbonate group, a 1-naphthyl carbonate group, a 2-naphthyl carbonate group, a 1-azulenyl carbonate group, a 2-tolyl carbonate group, a 3-tolyl carbonate group, a 4-tolyl carbonate group, a 2-chlorophenyl carbonate group, a 3-chlorophenyl carbonate group, a 4-chlorophenyl carbonate group, a 2,4-xylyl carbonate group, a 2,6-xylyl carbonate group, a 3,5-xylyl carbonate group, a 2,4,6-mesityl carbonate group, a 3,5-bistrifluoromethylphenyl carbonate group, and a pentafluorophenyl carbonate group, etc.

[0082] (R 6 ) As for the alkylsulfonyl group, examples thereof include the same ones as the above alkylsulfonyl group (RC5). From the viewpoint of availability of raw materials, preferably, they are methylsulfonyl, ethylsulfonyl, butylsulfonyl, trifluoromethanesulfonyl, nonafluorobutanesulfonyl, and perfluorooctanesulfonyl.

[0083] (R 6) As for the arylsulfonyl group, those similar to the above arylsulfonyl group (RC6) can be mentioned, and from the viewpoint of availability of raw materials, benzene sulfonyl, 4-toluenesulfonyl, 2-nitrobenzene sulfonyl and pentafluorobenzene sulfonyl are preferable.

[0084] (R 6 ) As for the halogen atom, fluorine atom, chlorine atom, bromine atom, iodine atom and the like can be mentioned, and from the viewpoints of availability of raw materials and ease of synthesis, fluorine atom, chlorine atom and bromine atom are preferable.

[0085] In the above compound, regarding the steric structure (E, Z), it may be either one or a mixture.

[0086] The synthesis method of the sulfonamide compound contained in the nonionic photoacid generator (A) of the present invention is not particularly limited as long as the target product can be synthesized. For example, the compound of general formula (1) can be produced by the method described below.

[0087]

Chemical formula

[0088] In the above reaction formula, R 1 ~R 3 and R f are the same as the definitions in general formula (1). The first-stage reaction is a precursor (PR1), R 1 SO 2A sulfonic acid halide equivalent represented by X, a base (sodium hydrogen carbonate, potassium carbonate, sodium hydroxide, potassium hydroxide, pyridine, chloropyridine, dichloropyridine, lutidine, 2,6-di-tert-butylpyridine, triethylamine, ethyldiisopropylamine, diazabicycloundecene (DBU), tetramethylpiperidine (TMP), tetramethylguanidine (TMG), hexamethyldisilazane (HMDS), potassium tert-butoxide, lithium diisopropylamide, sodium hexamethyldisilazane, etc.) is reacted in an organic solvent (toluene, butyl acetate, acetonitrile, dimethylformamide (DMF), dimethylacetamide (DMAc), dichloromethane, chloroform, benzotrifluoride, etc.) or in water at -78°C to reflux conditions for 5 minutes to 3 hours. After completion of the reaction, the precipitated solid is filtered or extracted with a suitable solvent to obtain a precursor (PR2). (PR2) can be recrystallized or washed with a solvent for purification as needed. In some cases, the subsequent reaction can be carried out without purification.

[0089] The second-stage reaction is carried out with the precursor (PR2), R f SO 2 A sulfonic acid halide equivalent represented by X, a base (sodium hydrogen carbonate, potassium carbonate, pyridine, chloropyridine, dichloropyridine, 2,6-di-tert-butylpyridine, triethylamine, ethyldiisopropylamine, TMP, TMG, HMDS, potassium tert-butoxide, lithium diisopropylamide, sodium bishexamethyldisilazane, etc.) is reacted in an organic solvent (toluene, butyl acetate, acetonitrile, DMF, DMAc, dichloromethane, chloroform, benzotrifluoride, etc.) at -78 to 30°C for 5 minutes to 3 hours. After completion of the reaction, the precipitated solid is filtered or extracted with a suitable solvent and the volatile components are distilled off to obtain a sulfonamide compound of the general formula (1) as a solid. The obtained solid can be purified by column chromatography, washing with an organic solvent, recrystallization, etc. as needed.

[0090] Since the nonionic photoacid generator (A) of the present invention generates a super-strong acid upon light irradiation, it is suitable for use in a resin composition for photolithography (resist).

[0091] In order to facilitate the dissolution of the nonionic photoacid generator (A) of the present invention in the resist material, it may be dissolved in a solvent that does not inhibit the reaction in advance.

[0092] Solvents that facilitate dissolution in the resist material include carbonates (such as propylene carbonate, ethylene carbonate, 1,2-butylene carbonate, dimethyl carbonate, and diethyl carbonate), esters (such as ethyl acetate, ethyl lactate, β-propiolactone, β-butyrolactone, γ-butyrolactone, δ-valerolactone, and ε-caprolactone), ethers (such as ethylene glycol monomethyl ether, propylene glycol monoethyl ether, diethylene glycol monobutyl ether, dipropylene glycol dimethyl ether, triethylene glycol diethyl ether, and tripropylene glycol dibutyl ether), and ether esters (such as ethylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, and diethylene glycol monobutyl ether acetate).

[0093] When using a solvent, the usage ratio of the solvent is preferably 15 to 1000 parts by weight, more preferably 30 to 500 parts by weight, based on 100 parts by weight of the nonionic photoacid generator (A) of the present invention.

[0094] Since the resin composition (Q) for photolithography of the present invention contains the nonionic photoacid generator (A) as an essential component, by performing ultraviolet irradiation and post-exposure baking (PEB), a difference in solubility in the developer between the exposed portion and the unexposed portion is created. The nonionic photoacid generator (A) can be used alone or in combination of two or more, and can also be used in combination with an ionic photoacid generator such as a sulfonium salt. Examples of the resin composition (Q) for photolithography include a mixture of a negative-type chemically amplified resin (QN) and a nonionic photoacid generator (A); and a mixture of a positive-type chemically amplified resin (QP) and a nonionic photoacid generator (A).

[0095] The negative-type chemically amplified resin (QN) is composed of a phenolic hydroxyl group-containing resin (QN1) and a crosslinking agent (QN2).

[0096] The phenolic hydroxyl group-containing resin (QN1) is not particularly limited as long as it is a resin containing a phenolic hydroxyl group. For example, novolak resin, polyhydroxystyrene, a copolymer of hydroxystyrene, a copolymer of hydroxystyrene and styrene, a copolymer of hydroxystyrene, styrene and a (meth)acrylic acid derivative, a phenol / xylene glycol condensation resin, a cresol / xylene glycol condensation resin, a polyimide containing a phenolic hydroxyl group, a polyamic acid containing a phenolic hydroxyl group, and a phenol-dicyclopentadiene condensation resin are used. Among these, novolak resin, polyhydroxystyrene, a copolymer of hydroxystyrene, a copolymer of hydroxystyrene and styrene, a copolymer of hydroxystyrene, styrene and a (meth)acrylic acid derivative, and a phenol / xylene glycol condensation resin are preferred. These phenolic hydroxyl group-containing resins (QN1) may be used alone or in combination of two or more.

[0097] The above novolak resin can be obtained, for example, by condensing phenols and aldehydes in the presence of a catalyst. Examples of the phenols include phenol, o-cresol, m-cresol, p-cresol, o-ethylphenol, m-ethylphenol, p-ethylphenol, o-butylphenol, m-butylphenol, p-butylphenol, 2,3-xylenol, 2,4-xylenol, 2,5-xylenol, 2,6-xylenol, 3,4-xylenol, 3,5-xylenol, 2,3,5-trimethylphenol, 3,4,5-trimethylphenol, catechol, resorcinol, pyrogallol, 1-naphthol, and 2-naphthol. Examples of the aldehydes include formaldehyde, paraformaldehyde, acetaldehyde, and benzaldehyde.

[0098] Examples of the novolak resin include phenol / formaldehyde condensation novolak resin, cresol / formaldehyde condensation novolak resin, and phenol / naphthol / formaldehyde condensation novolak resin.

[0099] Further, the phenolic hydroxyl group-containing resin (QN1) may contain a phenolic low-molecular compound as a part of the components. Examples of the phenolic low molecular weight compound include 4,4'-dihydroxydiphenylmethane, 4,4'-dihydroxydiphenyl ether, tris(4-hydroxyphenyl)methane, 1,1-bis(4-hydroxyphenyl)-1-phenylethane, tris(4-hydroxyphenyl)ethane, 1,3-bis[1-(4-hydroxyphenyl)-1-methylethyl]benzene, 1,4-bis[1-(4-hydroxyphenyl)-1-methylethyl]benzene, 4,6-bis[1-(4-hydroxyphenyl)-1-methylethyl]-1,3-dihydroxybenzene, 1,1-bis(4-hydroxyphenyl)-1-[4-[1-(4-hydroxyphenyl)-1-methylethyl]phenyl]ethane, 1,1,2,2-tetra(4-hydroxyphenyl)ethane, and 4,4'-{1-[4-[1-(4-hydroxyphenyl)-1-methylethyl]phenyl]ethylidene}bisphenol. These phenolic low molecular weight compounds may be used alone or in combination of two or more.

[0100] When the content ratio of this phenolic low molecular weight compound in the phenolic hydroxyl group-containing resin (QN1) is based on 100% by weight of the phenolic hydroxyl group-containing resin (QN1), it is preferably 40% by weight or less, and more preferably 1 to 30% by weight.

[0101] From the viewpoints of the resolution, thermal shock resistance, thermal stability, residual film ratio, etc. of the obtained insulating film, the weight average molecular weight of the phenolic hydroxyl group-containing resin (QN1) is preferably 2000 or more, and more preferably 2000 to 20000. In addition, when the content ratio of the phenolic hydroxyl group-containing resin (QN1) in the negative-type chemically amplified resin (QN) is based on 100% by weight of the whole composition excluding the solvent, it is preferably 30 to 90% by weight, and more preferably 40 to 80% by weight. When the content ratio of this phenolic hydroxyl group-containing resin (QN1) is 30 to 90% by weight, it is preferable because the film formed using the photosensitive insulating resin composition has sufficient developability with an alkaline aqueous solution.

[0102] The crosslinking agent (QN2) is not particularly limited as long as it is a compound capable of crosslinking the phenolic hydroxyl group-containing resin (QN1) with the strong acid generated from the nonionic photoacid generator (A).

[0103] Examples of the crosslinking agent (QN2) include bisphenol A-based epoxy compounds, bisphenol F-based epoxy compounds, bisphenol S-based epoxy compounds, novolak resin-based epoxy compounds, resol resin-based epoxy compounds, poly(hydroxystyrene)-based epoxy compounds, oxetane compounds, methylol group-containing melamine compounds, methylol group-containing benzoguanamine compounds, methylol group-containing urea compounds, methylol group-containing phenol compounds, alkoxyalkyl group-containing melamine compounds, alkoxyalkyl group-containing benzoguanamine compounds, alkoxyalkyl group-containing urea compounds, alkoxyalkyl group-containing phenol compounds, carboxymethyl group-containing melamine resins, carboxymethyl group-containing benzoguanamine resins, carboxymethyl group-containing urea resins, carboxymethyl group-containing phenol resins, carboxymethyl group-containing melamine compounds, carboxymethyl group-containing benzoguanamine compounds, carboxymethyl group-containing urea compounds, and carboxymethyl group-containing phenol compounds.

[0104] Among these crosslinking agents (QN2), methylol group-containing phenol compounds, methoxymethyl group-containing melamine compounds, methoxymethyl group-containing phenol compounds, methoxymethyl group-containing glycoluril compounds, methoxymethyl group-containing urea compounds, and acetoxymethyl group-containing phenol compounds are preferred, and methoxymethyl group-containing melamine compounds (e.g., hexamethoxymethylmelamine), methoxymethyl group-containing glycoluril compounds, and methoxymethyl group-containing urea compounds are more preferred. The methoxymethyl group-containing melamine compounds are commercially available under trade names such as CYMEL300, CYMEL301, CYMEL303, CYMEL305 (manufactured by Mitsui Cyanamid Co., Ltd.), the methoxymethyl group-containing glycoluril compounds are commercially available under trade names such as CYMEL1174 (manufactured by Mitsui Cyanamid Co., Ltd.), and the methoxymethyl group-containing urea compounds are commercially available under trade names such as MX290 (manufactured by Sanwa Chemical Co., Ltd.).

[0105] The content of the crosslinking agent (QN2) is usually 5 to 60 mol%, preferably 10 to 50 mol%, and more preferably 15 to 40 mol% with respect to all the acidic functional groups in the phenolic hydroxyl group-containing resin (QN1) from the viewpoints of reduction of the residual film rate, meandering and swelling of the pattern, and developability.

[0106] Examples of the positive chemically amplified resin (QP) include an alkali-soluble resin (QP1) containing at least one acidic functional group such as a phenolic hydroxyl group, a carboxyl group, or a sulfonyl group, and a protecting group-introduced resin (QP2) in which some or all of the hydrogen atoms of the acidic functional groups in (QP1) are substituted with acid-dissociable groups. The protecting group-introduced resin (QP2) is alkali-insoluble or hardly alkali-soluble by itself. Note that the acid-dissociable group is a group that can dissociate in the presence of a super-strong acid generated from the nonionic photoacid generator (A).

[0107] Examples of the alkali-soluble resin (QP1) include a phenolic hydroxyl group-containing resin (QP11), a carboxyl group-containing resin (QP12), and a sulfonic acid group-containing resin (QP13). As the phenolic hydroxyl group-containing resin (QP11), the same resin as the above hydroxyl group-containing resin (QN1) can be used.

[0108] The carboxyl group-containing resin (QP12) is not particularly limited as long as it is a polymer having a carboxyl group, and can be obtained, for example, by vinyl polymerization of a carboxyl group-containing vinyl monomer (Va) and, if necessary, a hydrophobic group-containing vinyl monomer (Vb).

[0109] Examples of the carboxyl group-containing vinyl monomer (Va) include unsaturated monocarboxylic acids [(meth)acrylic acid, crotonic acid, cinnamic acid, etc.], unsaturated polyvalent (divalent to tetravalent) carboxylic acids [(anhydrous) maleic acid, itaconic acid, fumaric acid, citraconic acid, etc.], unsaturated polyvalent carboxylic acid alkyl (alkyl group having 1 to 10 carbon atoms) esters [monoalkyl maleate, monoalkyl fumarate, monoalkyl citraconate, etc.], and salts thereof [alkali metal salts (sodium salt, potassium salt, etc.), alkaline earth metal salts (calcium salt, magnesium salt, etc.), amine salts, ammonium salts, etc.]. Among these, unsaturated monocarboxylic acids are preferred from the viewpoints of polymerizability and availability, and (meth)acrylic acid is more preferred.

[0110] Examples of the hydrophobic group-containing vinyl monomer (Vb) include (meth)acrylate (Vb1) and aromatic hydrocarbon monomer (Vb2).

[0111] Examples of the (meth)acrylate (Vb1) include alkyl (meth)acrylates having an alkyl group with 1 to 20 carbon atoms [methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, etc.] and alicyclic group-containing (meth)acrylates [dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, isobornyl (meth)acrylate, etc.].

[0112] Examples of the aromatic hydrocarbon monomer (Vb2) include hydrocarbon monomers having a styrene skeleton [styrene, α-methylstyrene, vinyltoluene, 2,4-dimethylstyrene, ethylstyrene, isopropylstyrene, butylstyrene, phenylstyrene, cyclohexylstyrene, benzylstyrene, etc.] and vinylnaphthalene.

[0113] In the carboxyl group-containing resin (QP12), the charged monomer molar ratio of (Va) / (Vb) is usually 10 to 100 / 0 to 90, preferably 10 to 80 / 20 to 90, and more preferably 25 to 85 / 15 to 75 from the viewpoint of developability.

[0114] The sulfonic acid group-containing resin (QP13) is not particularly limited as long as it is a polymer having a sulfonic acid group. For example, it can be obtained by vinyl polymerization of a sulfonic acid group-containing vinyl monomer (Vc) and, if necessary, a hydrophobic group-containing vinyl monomer (Vb). As the hydrophobic group-containing vinyl monomer (Vb), the same ones as those described above can be used.

[0115] Examples of the sulfonic acid group-containing vinyl monomer (Vc) include vinyl sulfonic acid, (meth)allyl sulfonic acid, styrene sulfonic acid, α-methylstyrene sulfonic acid, 2-(meth)acryloylamide-2-methylpropane sulfonic acid, and salts thereof. Examples of the salts include alkali metal (such as sodium and potassium) salts, alkaline earth metal (such as calcium and magnesium) salts, primary to tertiary amine salts, ammonium salts, and quaternary ammonium salts.

[0116] In the sulfonic acid group-containing resin (QP13), the charged monomer molar ratio of (Vc) / (Vb) is usually 10 to 100 / 0 to 90, preferably 10 to 80 / 20 to 90, and more preferably 25 to 85 / 15 to 75 from the viewpoint of developability.

[0117] The HLB value of the alkali-soluble resin (QP1) varies depending on the resin skeleton of the alkali-soluble resin (QP1), but is preferably 4 to 19, more preferably 5 to 18, and particularly preferably 6 to 17. If the HLB value is 4 or more, the developability is further improved when developing, and if it is 19 or less, the water resistance of the cured product is further improved.

[0118] Note that the HLB value in the present invention is the HLB value determined by the Oda method, which is the hydrophilic-hydrophobic balance value and can be calculated from the ratio of the organic value to the inorganic value of the organic compound. <Method for Evaluating HLB> HLB ≒ 10 × inorganic property / organic property In addition, the values of the inorganic property and the organic property are described in detail on page 501 of the literature "Synthesis and Applications of Surfactants" (published by Makino Shoten, written by Oda and Teramura); or on page 198 of "Introduction to New Surfactants" (written by Takehiko Fujimoto, published by Sanyo Chemical Industries, Ltd.).

[0119] Examples of the acid dissociable group in the protecting group-introducing resin (QP2) include a substituted methyl group, a 1-substituted ethyl group, a 1-branched alkyl group, a silyl group, a germyl group, an alkoxycarbonyl group, an acyl group, and a cyclic acid dissociable group. These may be used alone or in combination of two or more.

[0120] Examples of the substituted methyl group include a methoxymethyl group, a methylthiomethyl group, an ethoxymethyl group, an ethylthiomethyl group, a methoxyethoxymethyl group, a benzyloxymethyl group, a benzylthiomethyl group, a phenacyl group, a bromophenacyl group, a methoxyphenacyl group, a methylthiophenacyl group, an α-methylphenacyl group, a cyclopropylmethyl group, a benzyl group, a diphenylmethyl group, a triphenylmethyl group, a bromobenzyl group, a nitrobenzyl group, a methoxybenzyl group, a methylthiobenzyl group, an ethoxybenzyl group, an ethylthiobenzyl group, a piperonyl group, a methoxycarbonylmethyl group, an ethoxycarbonylmethyl group, a propoxycarbonylmethyl group, an isopropoxycarbonylmethyl group, a butoxycarbonylmethyl group, and a tert-butoxycarbonylmethyl group.

[0121] Examples of the 1-substituted ethyl group include a 1-methoxyethyl group, a 1-methylthioethyl group, a 1,1-dimethoxyethyl group, a 1-ethoxyethyl group, a 1-ethylthioethyl group, a 1,1-diethoxyethyl group, a 1-ethoxypropyl group, a 1-propoxyethyl group, a 1-cyclohexyloxyethyl group, a 1-phenoxyethyl group, a 1-phenylthioethyl group, a 1,1-diphenoxyethyl group, a 1-benzyloxyethyl group, a 1-benzylthioethyl group, a 1-cyclopropylethyl group, a 1-phenylethyl group, a 1,1-diphenylethyl group, a 1-methoxycarbonylethyl group, a 1-ethoxycarbonylethyl group, a 1-propoxycarbonylethyl group, a 1-isopropoxycarbonylethyl group, a 1-butoxycarbonylethyl group, and a 1-tert-butoxycarbonylethyl group.

[0122] Examples of the 1-branched alkyl group include an isopropyl group, a sec-butyl group, a tert-butyl group, a 1,1-dimethylpropyl group, a 1-methylbutyl group, and a 1,1-dimethylbutyl group.

[0123] Examples of the silyl group include tricalbilsilyl groups such as a trimethylsilyl group, an ethyldimethylsilyl group, a diethylmethylsilyl group, a triethylsilyl group, an isopropyldimethylsilyl group, a diisopropylmethylsilyl group, a triisopropylsilyl group, a tert-butyldimethylsilyl group, a di-tert-butylmethylsilyl group, a tri-tert-butylsilyl group, a dimethylphenylsilyl group, a methyldiphenylsilyl group, and a triphenylsilyl group.

[0124] Examples of the germyl group include tricalbilgermyl groups such as a trimethylgermyl group, an ethyldimethylgermyl group, a methyldiethylgermyl group, a triethylgermyl group, an isopropyldimethylgermyl group, a methyldiisopropylgermyl group, a triisopropylgermyl group, a tert-butyldimethylgermyl group, a di-tert-butylmethylgermyl group, a tri-tert-butylgermyl group, a dimethylphenylgermyl group, a methyldiphenylgermyl group, and a triphenylgermyl group.

[0125] Examples of the alkoxycarbonyl group include a methoxycarbonyl group, an ethoxycarbonyl group, an isopropoxycarbonyl group, and a tert-butoxycarbonyl group.

[0126] Examples of the acyl group include an acetyl group, a propionyl group, a butyryl group, a heptanoyl group, a hexanoyl group, a valeryl group, a pivaloyl group, an isovaleryl group, a lauroyl group, a myristoyl group, a palmitoyl group, a stearoyl group, an oxalyl group, a malonyl group, a succinyl group, a glutaryl group, an adipoyl group, a piperoyl group, a suberoyl group, an azelaoyl group, a sebacoyl group, an acryloyl group, a propioloyl group, a methacryloyl group, a crotonoyl group, an oleoyl group, a maleoyl group, a fumaroyl group, a mesaconoyl group, a camphoroyl group, a benzoyl group, a phthaloyl group, an isophthaloyl group, a terephthaloyl group, a naphthoyl group, a toluoyl group, a hydroatropoyl group, an atropoyl group, a cinnamoyl group, a furoyl group, a tenoyl group, a nicotinoyl group, an isonicotinoyl group, a p-toluenesulfonyl group, and a mesyl group.

[0127] Examples of the cyclic acid-dissociable group include a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, a cyclohexenyl group, a 4-methoxycyclohexyl group, a tetrahydropyranyl group, a tetrahydrofuranyl group, a tetrahydrothiopyranyl group, a tetrahydrothiofuranyl group, a 3-bromotetrahydropyranyl group, a 4-methoxytetrahydropyranyl group, a 4-methoxytetrahydrothiopyranyl group, and a 3-tetrahydrothiophene-1,1-dioxide group.

[0128] Among these acid-dissociable groups, a tert-butyl group, a benzyl group, a 1-methoxyethyl group, a 1-ethoxyethyl group, a trimethylsilyl group, a tert-butoxycarbonyl group, a tert-butoxycarbonylmethyl group, a tetrahydropyranyl group, a tetrahydrofuranyl group, a tetrahydrothiopyranyl group, and a tetrahydrothiofuranyl group are preferable.

[0129] The introduction rate of the acid-dissociable group in the protecting group-introduced resin (QP2) {the ratio of the number of acid-dissociable groups to the total number of unprotected acidic functional groups and acid-dissociable groups in the protecting group-introduced resin (QP2)} cannot be generally defined depending on the type of the acid-dissociable group and the alkali-soluble resin into which the group is introduced, but is preferably 10 to 100%, and more preferably 15 to 100%.

[0130] The polystyrene-reduced weight average molecular weight (hereinafter referred to as "Mw") measured by gel permeation chromatography (GPC) of the protecting group-introduced resin (QP2) is preferably 1,000 to 150,000, and more preferably 3,000 to 100,000.

[0131] The ratio (Mw / Mn) of Mw of the protecting group-introduced resin (QP2) to the polystyrene-reduced number average molecular weight (hereinafter referred to as "Mn") measured by gel permeation chromatography (GPC) is usually 1 to 10, and preferably 1 to 5.

[0132] The content of the nonionic photoacid generator (A) based on the weight of the solid content of the photolithography resin composition (Q) is preferably 0.001 to 20% by weight, more preferably 0.01 to 15% by weight, and particularly preferably 0.05 to 7% by weight. If it is 0.001% by weight or more, the sensitivity to ultraviolet rays can be more favorably exhibited, and if it is 20% by weight or less, the physical properties of the insoluble portion with respect to the alkali developer can be more favorably exhibited.

[0133] The resist using the photolithography resin composition (Q) of the present invention may contain a quencher (acid diffusion controller) for the purpose of improving the shape of the pattern after exposure, changes over time, and the like. As the quencher, a pK larger than the acid generated by the nonionic photoacid generator (A) aThe compound having a basic site shown is not particularly limited. For example, known amines (tripentylamine, triisopropanolamine, dicyclohexylamine, N,N-dicyclohexylmethylamine, etc.), known pyridines (pyridine, 2,6-lutidine, 2,6-di-tert-butylpyridine, 2,6-diphenylpyridine, etc.), known anilines (2,6-diisopropylaniline, etc.), known imidazoles (2,4,5-triphenylimidazole, 4,5-diphenylimidazole, 2-phenylimidazole, etc.), and salts of known onium and weak acid anions that decompose to generate a weak acid upon exposure (triphenylsulfonium benzoate, triphenylsulfonium salicylate, triphenylsulfonium 3,5-bistrifluoromethylbenzoate, diphenyliodonium pentafluorobenzoate, 4-isobutyl-4'-tolyl iodonium 4-fluorobenzoate, etc.) can be mentioned. The content of the quencher depends on the content of the nonionic photoacid generator (A), but is 5% by weight or less, preferably 3% by weight or less, based on the total solid content of the photoresist resin composition (Q). If it exceeds 5% by weight, there is a problem that the effective concentration of the acid generated during exposure decreases and no pattern can be obtained after development.

[0134] The resist using the photoresist resin composition (Q) of the present invention can be formed, for example, by dissolving (dissolving and dispersing when containing inorganic fine particles) a resin solution in a predetermined organic solvent, applying it to a substrate using a known method such as spin coating, curtain coating, roll coating, spray coating, screen printing, etc., and then drying the solvent by heating or blowing hot air.

[0135] As the organic solvent (resist solvent) for dissolving the resin composition (Q) for photolithography, there is no particular limitation as long as it can dissolve the resin composition and can be adjusted to physical properties (such as viscosity) applicable to spin coating or the like. For example, known solvents such as N-methylpyrrolidone, DMF, dimethyl sulfoxide, toluene, ethanol, cyclohexanone, methanol, methyl ethyl ketone, ethyl acetate, butyl acetate, ethyl lactate, γ-butyrolactone, propylene glycol monomethyl ether acetate, acetone, and xylene can be used. Among these solvents, from the viewpoint of drying temperature and the like, those having a boiling point of 200°C or lower (toluene, ethanol, cyclohexanone, methanol, methyl ethyl ketone, ethyl acetate, butyl acetate, ethyl lactate, propylene glycol monomethyl ether acetate, acetone, and xylene) are preferable, and they can be used alone or in combination of two or more. When using an organic solvent, the blending amount of the solvent is not particularly limited, but based on the weight of the solid content of the resin composition (Q) for photolithography, usually 30 to 1,000% by weight is preferable, 40 to 900% by weight is more preferable, and 50 to 800% by weight is particularly preferable.

[0136] The drying conditions of the resin solution after coating vary depending on the solvent used, but are preferably carried out in the range of 50 to 200°C for 1 to 30 minutes, and are appropriately determined by the residual solvent amount (% by weight) of the resin composition (Q) for photolithography after drying.

[0137] After forming a resist on the substrate, light irradiation in the shape of a wiring pattern is performed. Then, after performing post-exposure baking (PEB), alkali development is performed to form a wiring pattern.

[0138] As a method of light irradiation, a method of exposing the resist with actinic rays through a photomask having a wiring pattern can be mentioned. As the actinic rays used for light irradiation, in the present invention There is no particular limitation as long as it can decompose the nonionic photoacid generator (A) in the resin composition (Q) for photolithography. Examples of the actinic ray include low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, xenon lamps, metal halide lamps, electron beam irradiation devices, X-ray irradiation devices, lasers (argon lasers, argon fluoride (ArF) excimer lasers, krypton fluoride (KrF) excimer lasers, dye lasers, nitrogen lasers, LEDs, helium cadmium lasers, etc.). Among these, high-pressure mercury lamps, ultra-high-pressure mercury lamps, LEDs, and krypton fluoride (KrF) excimer lasers are preferred.

[0139] The temperature of post-exposure baking (PEB) is generally 40 to 200°C, preferably 50 to 190°C, and more preferably 60 to 180°C. If it is less than 40°C, the deprotection reaction or cross-linking reaction cannot proceed sufficiently, resulting in insufficient difference in solubility between the UV-irradiated part and the non-UV-irradiated part of the photoresist composition, and thus no pattern can be formed. If it is higher than 200°C, there is a problem of reduced productivity. The heating time is generally 0.5 to 120 minutes. If it is less than 0.5 minutes, it is difficult to control the time and temperature, and if it is more than 120 minutes, there is a problem of reduced productivity.

[0140] Examples of the alkali development method include a method of dissolving and removing using an alkali developer to form a wiring pattern shape. The alkali developer is not particularly limited as long as it can create a difference in solubility between the UV-irradiated part and the non-UV-irradiated part of the photoresist composition (Q) for photolithography. Examples of the alkali developer include aqueous sodium hydroxide solution, aqueous potassium hydroxide solution, sodium hydrogen carbonate, and aqueous tetramethylammonium salt solution. These alkali developers may be added with a water-soluble organic solvent. Examples of the water-soluble organic solvent include methanol, ethanol, isopropyl alcohol, THF, N-methylpyrrolidone, etc.

[0141] Examples of the development method include a dip method, a shower method, and a spray method using an alkali developer, and the spray method is preferred. The temperature of the developer is preferably used at 25 to 40°C. The development time is appropriately determined according to the thickness of the resist.

Example

[0142] The present invention will be further described below with reference to Examples and Comparative Examples, but the present invention is not limited thereto. Hereinafter, unless otherwise specified, % represents % by weight and parts represent parts by weight.

[0143] <Production Example 1> <Synthesis of 9-fluorenone hydrazone [Precursor (P1)]> Using 9-fluorenone as a raw material, the precursor (P1) was obtained according to the method described in the literature (Angew. Chem., Int. Ed., 2019, 58, 8762.).

[0144] <Production Example 2> <Synthesis of 2-butyl-9-fluorenone hydrazone [Precursor (P2)]> Using 2-bromo-9-fluorenone as a raw material, an alkylated product was obtained in the same manner as the method described in Republished 2014 / 084269. Subsequently, using the obtained alkylated product, the precursor (P2) was obtained according to the method described in Production Example 1.

[0145] <Production Example 3> <Synthesis of 9(10H)-anthracenone hydrazone [Precursor (P3)]> Using anthrone as a raw material, the precursor (P3) was obtained in the same manner as the method described in the literature (Chem. Sci., 2011, 2, 2029.).

[0146] <Production Example 4> <Synthesis of thioxanthone hydrazone [Precursor (P4)]> Using thioxanthone as a raw material, the precursor (P4) was synthesized according to the synthesis method described in the literature (Angew. Chem., Int. Ed., 2010, 49, 6580.).

[0147] <Production Example 5> <Synthesis of Precursor (P5)> The precursor (P4) synthesized in Production Example 4 was dispersed in dichloromethane, and triethylamine was added dropwise to the slurry cooled to -78°C, followed by stirring for 5 minutes. Subsequently, pentafluorobenzenesulfonyl chloride was added dropwise, and after stirring for 1 hour, the temperature was raised to 0°C. After adding deionized water to stop the reaction, the precipitated solid was filtered and dried under reduced pressure to obtain the precursor (P5) of the following formula.

[0148]

Chemical formula

[0149] <Production Example 6> <Synthesis of Precursor (P6)> Using 4-hydroxycarbazole as a raw material, a ketone compound was synthesized according to the method described in the literature (J. Photopolym. Sci. Technol., 2018, 31, 37.). Subsequently, using the obtained ketone compound, the precursor (P6) of the following formula was obtained according to the method described in Production Example 1.

[0150]

Chemical formula

[0151] <Production Example 7> <Synthesis of Precursor (P7)> The corresponding ketone compound was synthesized according to the method described in JP 2010-024290. Subsequently, using the obtained ketone compound, the precursor (P7) of the following formula was obtained according to the method described in Production Example 1.

[0152]

Chemical formula

[0153] <Production Example 8> <Synthesis of Precursor (P8)> Using 6,7-dimethyl-1-tetralone as a raw material, a precursor (P8) of the following formula was obtained in the same manner as in Production Example 1 and then Production Example 5, except that pentafluorobenzenesulfonyl chloride was replaced with 2-nitrobenzenesulfonyl chloride.

[0154] [Chemical formula]

[0155] <Production Example 9> <Synthesis of Precursor (P9)> Using 6-methoxy-2-naphthalenepropionic acid as a raw material, 2,3-dihydro-7-methoxy-1H-benz[e]inden-1-one, which is a ketone form, was synthesized according to the method described in the literature (Synthesis, 2005, 1789.). Subsequently, using the obtained ketone form, a precursor (P9) of the following formula was obtained according to the method described in Production Example 1.

[0156] [Chemical formula]

[0157] <Production Example 10> <Synthesis of Precursor (P10)> Using 2-naphthol and ethyl 2-bromooctanoate as raw materials, 2-hexylnaphtho[2,1-b]furan-1(2H)-one, which is a ketone form, was synthesized according to the method described in JP-A-2011-209719. Subsequently, using the obtained ketone form, a precursor (P10) of the following formula was obtained according to the method described in Production Example 1.

[0158] [Chemical formula]

[0159] <Production Example 11> <Synthesis of Precursor (P11)> Using methyl 1-hydroxy-2-naphthoate and methyl 2-bromopropionate as raw materials, 2-methylnaphtho[1,2-b]furan-3(2H)-one, which is a ketone compound, was synthesized according to the method described in the literature (Synthetic Communications., 2012, 42, 989.). Subsequently, using the obtained ketone compound, a precursor (P11) of the following formula was obtained according to the method described in Production Example 1.

[0160]

Chemical formula

[0161] <Production Example 12> <Synthesis of Precursor (P12)> Using diphenyl sulfide and heptanoyl chloride as raw materials, 1-[4-(phenylthio)phenyl]-1-heptanone, which is a ketone compound, was synthesized according to the method described in JP 2009-242469, except that the solvent was dichloromethane. Subsequently, using the obtained ketone compound, a precursor (P12) of the following formula was obtained according to the method described in Production Example 1.

[0162]

Chemical formula

[0163] <Production Example 13> <Synthesis of Precursor (P13)> Using 9-ethylcarbazole as a raw material, the corresponding ketone compound was synthesized according to the method described in JP 2009-242469. Subsequently, using the obtained ketone compound, a precursor (P13) of the following formula was obtained according to the method described in Production Example 1.

[0164]

Chemical formula

[0165] <Production Example 14> <Synthesis of Precursor (P14)> According to the method described in JP-A-2016-113504, 2-benzyl-3,3-dimethyl-3H-indole was synthesized, and then the corresponding ketone was synthesized according to the method described in the literature (Chem. Sci., 2016, 7, 346.). Next, using the obtained ketone, the precursor (P14) of the following formula was obtained according to the method described in Production Example 1.

[0166]

Chemical formula

[0167] <Production Example 15> <Synthesis of Precursor (P15)> Using 2-amino-4-methoxyphenol and 2,2-dibromoacetophenone (synthesized according to the literature Chem. Asian J., 2012, 7, 2240.) as raw materials, 2-benzoyl-5-methoxy-1,3-benzoxazole, which is a ketone, was synthesized according to the method described in the literature (J. Org. Chem., 2016, 81, 51.). Next, using the obtained ketone, the precursor (P15) of the following formula was obtained according to the method described in Production Example 1.

[0168]

Chemical formula

[0169] <Production Example 16> <Synthesis of Precursor (P16)> Using benzothiazole and ethyl chloroglyoxylate as raw materials, the corresponding ketone was synthesized according to the method described in the literature (Synthesis, 2011, 1633.), and then the corresponding hydrazone was synthesized according to the method described in Production Example 1. Next, the precursor (P16) of the following formula was obtained in the same manner as in Production Example 5, except that pentafluorobenzenesulfonyl chloride was changed to p-toluenesulfonyl chloride.

[0170]

Chemical formula

[0171] <Production Example 17> <Synthesis of Precursor (P17)> Using benzothiazole and 4-cyanobenzoyl chloride as raw materials, 4-(2-benzothiazolylcarbonyl)benzonitrile, which is a ketone compound, was synthesized according to the method described in the literature (Synlett, 2013, 24, 2233.). Subsequently, using the obtained ketone compound, the precursor (P17) of the following formula was obtained according to the method described in Production Example 1.

[0172]

Chemical formula

[0173] <Production Example 18> <Synthesis of Precursor (P18)> Using 2-aminobenzenethiol and 3-(dimethylamino)-1-phenyl-2-propen-1-one as raw materials, 1-(2-benzothiazolyl)-2-phenyl-1,2-ethanedione, which is a ketone compound, was synthesized according to the method described in the literature (Green Chem., 2016, 18, 402.). Subsequently, using the obtained ketone compound, the precursor (P18) of the following formula was obtained according to the method described in Production Example 1.

[0174]

Chemical formula

[0175] <Production Example 19> <Synthesis of Precursor (P19)> Using 3-amino-2-naphthalenethiol as a raw material, 2-acetylnaphtho[2,3-d]thiazole, which is a ketone compound, was synthesized according to the method described in WO2015 / 087094. Subsequently, using the obtained ketone compound, the precursor (P19) of the following formula was obtained according to the method described in Production Example 1.

[0176]

Chem.

[0177] <Example 1> <Synthesis of Compound (A1)> 10 parts of the precursor (P1) synthesized in Production Example 1 was dispersed in 350 parts of dichloromethane, and the resulting slurry was cooled to 0 °C. 30 parts of 2,6-di-tert-butylpyridine was added dropwise thereto, and the mixture was stirred for 5 minutes. Subsequently, 35 parts of trifluoromethanesulfonic anhydride was added dropwise, and the mixture was stirred for 1 hour. Deionized water was added to the reaction solution to terminate the reaction, and the organic layer was washed three times with deionized water. The organic layer was concentrated to obtain 18 parts of yellow solid Compound (A1).

[0178] <Example 2> <Synthesis of Compound (A2)> Using the precursor (P1) synthesized in Production Example 1 as a raw material, 23 parts of Compound (A2) was obtained in the same manner as in Example 1, except that the trifluoromethanesulfonic anhydride was replaced with 72 parts of nonafluorobutanesulfonic anhydride.

[0179] <Example 3> <Synthesis of Compound (A3)> Using the precursor (P1) synthesized in Production Example 1 as a raw material, 20 parts of Compound (A3) was obtained in the same manner as in Example 1, except that the trifluoromethanesulfonic anhydride was replaced with 30 parts of pentafluorobenzenesulfonyl chloride.

[0180] <Example 4> <Synthesis of Compound (A4)> Using the precursor (P1) synthesized in Production Example 1 as a raw material, 15 parts of Compound (A4) was obtained in the same manner as in Example 1, except that the trifluoromethanesulfonic anhydride was replaced with 36 parts of perfluoropropane-1,3-disulfonyldifluoride.

[0181] <Example 5> <Synthesis of Compound (A5)> Using the precursor (P2) synthesized in Production Example 2 as a raw material, 14 parts of compound (A5) were obtained in the same manner as in Example 1.

[0182] <Example 6> <Synthesis of Compound (A6)> 14 parts of compound (A6) of the following formula were obtained in the same manner as in Example 1, except that the precursor synthesized according to the method described in Production Example 1 was used with 11H-benzo[b]fluorene-11-one as a raw material.

[0183]

Chemical formula

[0184] <Example 7> <Synthesis of Compound (A7)> 10 parts of the precursor (P3) synthesized in Production Example 3 were dispersed in 320 parts of dichloromethane, and 19 parts of N-ethyldiisopropylamine were added dropwise to the slurry cooled to 0 °C and stirred for 5 minutes. Then, 33 parts of trifluoromethanesulfonic anhydride were added dropwise and stirred for 1 hour. Deionized water was added to the reaction solution to stop the reaction, and the organic layer was washed 3 times with deionized water. The organic layer was concentrated to obtain 16 parts of a yellowish-brown solid compound (A7).

[0185] <Examples 8 to 10> <Synthesis of Compounds (A8) to (A10)> Compounds (A8) to (A10) were synthesized in the same manner as the synthesis method described in Example 7, except that the precursors synthesized according to the method described in Production Example 1 or 3 were used from the corresponding raw materials.

[0186] <Example 11> <Synthesis of Compound (A11)> Using the precursor (P4) synthesized in Production Example 4 as a raw material, 14 parts of compound (A11) were obtained in the same manner as in Example 7.

[0187] <Example 12> <Synthesis of Compound (A12)> 10 parts of the precursor (P5) synthesized in Production Example 5, 150 parts of dichloromethane, 4.2 parts of N - ethyldiisopropylamine, and 7.4 parts of trifluoromethanesulfonic anhydride were used, and 10 parts of compound (A12) were obtained in the same manner as in Example 7 except for the above.

[0188] <Examples 13 and 14> <Synthesis of Compounds (A13) and (A14)> Compounds (A13) and (A14) were synthesized in the same manner as the synthesis method described in Example 7, except that the precursor synthesized according to the method described in Production Example 4 from the corresponding raw materials was used.

[0189] <Example 15> <Synthesis of Compound (A15)> 10 parts of compound (A15) were obtained in the same manner as in Example 7, except that the precursor synthesized in the same manner as in Production Example 5 with pentafluorobenzenesulfonyl chloride replaced by methanesulfonyl chloride from the corresponding raw materials (synthesized according to the method described in Production Example 4) was used.

[0190] <Examples 16 to 22> <Synthesis of Compounds (A16) to (A22)> Compounds (A16) to (A22) were synthesized in the same manner as the synthesis method described in Example 1 or 7, except that the precursor synthesized according to the method described in Production Example 1 or 4 from the corresponding raw materials was used.

[0191] <Example 23> <Synthesis of Compound (A23)> Using the precursor (P6) synthesized in Production Example 6 as the raw material, 10 parts of the compound (A23) of the following formula were obtained in the same manner as the synthesis method described in Example 1.

[0192]

Chemical formula

[0193] <Example 24> <Synthesis of Compound (A24)> Using the precursor (P7) synthesized in Production Example 7 as a raw material, 16 parts of compound (A24) were obtained in the same manner as the synthesis method described in Example 1.

[0194] <Example 25> <Synthesis of Compound (A25)> 11 parts of compound (A25) were obtained in the same manner as Example 1, except that 10 parts of the precursor (P8) synthesized in Production Example 8 was used as the raw material, 180 parts of dichloromethane, 7.7 parts of 2,6-di-tert-butylpyridine, and 9.1 parts of trifluoromethanesulfonic anhydride were used.

[0195] <Examples 26 and 27> <Synthesis of Compounds (A26) and (A27)> Compounds (A26) and (A27) were synthesized in the same manner as Example 1, except that the precursors synthesized according to the method described in Production Example 1 from the corresponding raw materials were used.

[0196] <Examples 28 and 29> <Synthesis of Compounds (A28) and (A29)> Compounds (A28) and (A29) were synthesized in the same manner as Example 24, except that the precursors synthesized according to the method described in Production Example 7 from the corresponding raw materials were used.

[0197] <Example 30> <Synthesis of Compound (A30)> Using the precursor (P9) synthesized in Production Example 9 as a raw material, 15 parts of compound (A30) were obtained in the same manner as the synthesis method described in Example 1.

[0198] <Example 31> <Synthesis of Compound (A31)> 35 parts of compound (A31) were obtained in the same manner as Example 1, except that the precursor synthesized according to the method described in Production Example 7 from the corresponding raw materials was used as the raw material and 61 parts of heptadecafluorooctanesulfonic acid fluoride was used instead of trifluoromethanesulfonic anhydride.

[0199] <Example 32> <Synthesis of Compound (A32)> Using the precursor (P10) synthesized in Production Example 10 as a raw material and following the same synthesis method as described in Example 1, 14 parts of Compound (A32) were obtained.

[0200] <Example 33> <Synthesis of Compound (A33)> 16 parts of Compound (A33) were obtained in the same manner as in Example 32, except that the precursor synthesized according to the method described in Production Example 10 using 2-naphthol and 2-chloropropionyl chloride was used as a raw material.

[0201] <Examples 34 to 36> <Synthesis of Compounds (A34) to (A36)> Compounds (A34 to A36) were synthesized in the same manner as in Example 24, except that the precursors synthesized according to the method described in Production Example 7 from the corresponding raw materials were used.

[0202] <Example 37> <Synthesis of Compound (A37)> Using the precursor (P11) synthesized in Production Example 11 as a raw material and following the same synthesis method as described in Example 2, 22 parts of Compound (A37) were obtained.

[0203] <Example 38> <Synthesis of Compound (A38)> 12 parts of Compound (A38) were obtained in the same manner as in Example 37, except that the precursor synthesized in the same manner as the method described in Production Example 11 with methyl 2-bromopropionate replaced by methyl 2-bromooctanoate was used.

[0204] <Example 39> <Synthesis of Compound (A39)> 18 parts of Compound (A39) were obtained in the same manner as in Example 1, except that the precursor (P1) was changed to benzophenone hydrazone.

[0205] <Example 40> <Synthesis of Compound (A40)> Using the precursor (P12) synthesized in Production Example 12 as a raw material and following the same synthesis method as described in Example 1, 12 parts of compound (A40) were obtained.

[0206] <Example 41> <Synthesis of Compound (A41)> Using the precursor (P13) synthesized in Production Example 13 as a raw material and following the same synthesis method as described in Example 1, 10 parts of the compound (A41) of the following formula were obtained.

[0207]

Chemical formula

[0208] <Examples 42 to 44> <Synthesis of Compounds (A42) to (A44)> Using the precursors synthesized from the corresponding raw materials according to the method described in Production Example 1 and following the same synthesis method as described in Example 1 or 2, compounds (A42 to A44) were synthesized.

[0209] <Examples 45 and 46> <Synthesis of Compounds (A45) and (A46)> Compounds (A45) and (A46) were synthesized in the same manner as Example 1, except that the precursors synthesized from the corresponding raw materials according to the method described in Production Example 12 were used.

[0210] <Example 47> <Synthesis of Compound (A47)> Using the precursor (P14) synthesized in Production Example 14 as a raw material and following the same synthesis method as described in Example 1, 12 parts of compound (A47) were obtained.

[0211] <Example 48> <Synthesis of Compound (A48)> Using the precursor (P15) synthesized in Production Example 15 as a raw material and following the same synthesis method as described in Example 1, 13 parts of compound (A48) were obtained.

[0212] <Example 49> <Synthesis of Compound (A49)> Compound (A49) (11 parts) was obtained in the same manner as in Example 1, except that 10 parts of the precursor (P16) synthesized in Production Example 16 was used as the precursor (P1), 170 parts of dichloromethane, 7.1 parts of 2,6-di-tert-butylpyridine, and 8.4 parts of trifluoromethanesulfonic anhydride were used.

[0213] <Example 50> <Synthesis of Compound (A50)> Using the precursor (P17) synthesized in Production Example 17 as the raw material, 14 parts of compound (A50) was obtained in the same manner as the synthesis method described in Example 1.

[0214] <Example 51> <Synthesis of Compound (A51)> Using the precursor (P18) synthesized in Production Example 18 as the raw material, 18 parts of compound (A51) was obtained in the same manner as the synthesis method described in Example 2.

[0215] <Example 52> <Synthesis of Compound (A52)> Compound (A52) (15 parts) was obtained in the same manner as in Example 1, except that the hydrazone derivative (precursor) synthesized in the same manner as the method described in Production Example 16 using benzothiazole replaced with 1-methylbenzimidazole was used.

[0216] <Example 53> <Synthesis of Compound (A53)> Compound (A53) (12 parts) was obtained in the same manner as in Example 1, except that the precursor synthesized in the same manner as the method described in Production Example 15 using 2-amino-4-methoxyphenol replaced with 3-amino-2-naphthol was used.

[0217] <Example 54> <Synthesis of Compound (A54)> Using the precursor (P19) synthesized in Production Example 19 as the raw material, 13 parts of compound (A54) was obtained in the same manner as the synthesis method described in Example 1.

[0218] The structures and properties of Compounds (A1) to (A54) are described in Tables 1 to 4.

[0219]

Table 1

[0220]

Table 2

[0221]

Table 3

[0222] [In Table 3, R 3 The bonding position refers to the bonding position of the carbon atom to which R 3 -CR 2 represented by =N is bonded to R 3 .]

[0223]

Table 4

[0224] In Tables 1 to 4, H represents a hydrogen atom, Me represents a methyl group, Et represents an ethyl group, Pr represents a propyl group, Bu represents a butyl group, Hex represents a hexyl group, Ph represents a phenyl group, and Bz represents a benzoyl group.

[0225] <Comparative Example 1> <Synthesis of Ionic Photoacid Generator [Compound (A'1)]> 10 parts of triphenylsulfonium bromide was dispersed in 109 parts of chloroform, and 9.3 parts of sodium bis(trifluoromethanesulfonamide) and 109 parts of deionized water were added. After vigorously stirring for 1 hour, the mixture was allowed to stand and the separated aqueous layer was removed, and the organic layer was washed with water twice more. The organic layer was concentrated and dried in a vacuum dryer to obtain 13 parts of the ionic photoacid generator [Compound (A'1)] of the comparative example.

[0226] <Comparative Example 2> <Synthesis of Nonionic Photoacid Generator [Compound (A'2)]> 1,8-Naphthalimide trifluoromethanesulfonate (A’2) (manufactured by Aldrich) was used as it was.

[0227]

Chemical formula

[0228] <Examples 1 to 54, Comparative Examples 1 and 2> The i-line sensitivity and resist solvent solubility of the nonionic photoacid generators (A1) to (A54) obtained in Examples 1 to 54, the ionic photoacid generator (A’1) for comparison, and the nonionic photoacid generator (A’2) were evaluated by the following method, and the results are shown in Tables 5 and 6.

[0229] <i-line decomposition rate> 0.3 part of the compound of the synthesized Examples and Comparative Examples and 0.1 part of perfluorobenzene as a standard substance were dissolved in 100 parts of heavy acetonitrile, and 0.6 mL was injected into an NMR tube. 19 F-NMR analysis was performed. Then, using an ultraviolet irradiation device (manufactured by Oak Manufacturing Co., Ltd., HMW-661F-01), ultraviolet light with a wavelength limited by an L-34 filter (manufactured by Kenko Optics Co., Ltd., a filter that cuts light with a wavelength of less than 340 nm) was irradiated at 500 mJ·cm 2 The exposure was carried out. The integrated exposure amount was measured at a wavelength of 365 nm. The NMR tube after exposure was analyzed again by 19 F-NMR, and the i-line decomposition rate was calculated from the integral value of the 19 F-NMR signal of the compound before and after exposure (based on the standard substance). Since a higher decomposition rate at the same exposure amount indicates excellent performance as a photoacid generator, the i-line decomposition rate was evaluated as follows, and the results are shown in Tables 5 and 6. i-line decomposition rate = (Integral value of the compound signal before exposure - Integral value of the compound signal after exposure) / (Integral value of the compound signal before exposure)

[0230] <Solubility> The compounds of the examples and comparative examples were added to propylene glycol monomethyl ether acetate, a general-purpose resist solvent, to a concentration of 50%, stirred for one minute with a vortex mixer, then immersed in a thermostatic bath at 25°C and allowed to stand for one hour, and visually confirmed whether they were uniformly dissolved. In the case of non-uniformity, propylene glycol monomethyl ether acetate was added so that the concentration decreased by 5% each time, and the operation was repeated. When the concentration was 5% or less, it was repeated in 1% increments. The concentration at which it became uniform for the first time was defined as the solubility of the compound in the resist solvent. A higher solubility is excellent because when used as a photolithography resin composition, precipitation and phase separation are less likely to occur. The results are shown in Tables 5 and 6.

[0231] <Evaluation of Positive Photolithography Resin Composition> <Preparation of Positive Photolithography Resin Composition (QP-1)> 40 parts of the resin represented by the following formula, 60 parts of a novolak resin obtained by addition condensation of m-cresol and p-cresol in the presence of formaldehyde and an acid catalyst, and 1 part of the compound of the examples and comparative examples were dissolved in 152 parts of propylene glycol monomethyl ether acetate, and filtered through a membrane filter (pore size 0.45 μm, PTFE membrane) to prepare a positive photolithography resin composition (QP-1).

[0232]

Chemical formula

[0233] <Minimum Exposure Amount> After spin-coating the positive photoresist resin composition (QP-1) prepared above on a silicon wafer substrate and drying it, a photoresist layer having a film thickness of about 20 μm was obtained. This resist layer was prebaked at 130 °C for 6 minutes using a hot plate. Next, pattern exposure (i-line) was performed using TME-150RSC-12 (manufactured by Topcon Corporation), and post-exposure baking (PEB) was performed at 75 °C for 5 minutes using a hot plate. Then, development treatment was carried out for 5 minutes by an immersion method using a 2.38 wt% aqueous solution of tetramethylammonium hydroxide, followed by washing with running water and blowing with nitrogen to obtain a 10-μm line and space (L&S) pattern. Furthermore, the minimum exposure amount at which no residue of this pattern was observed below this level, that is, the minimum exposure amount [mJ / cm 2 required to form a resist pattern was measured. The lower the minimum exposure amount, the better it corresponds to the i-line sensitivity. The results are shown in Tables 5 and 6.

[0234] <Evaluation of Negative Photoresist Resin Composition> <Preparation of Negative Photoresist Resin Composition> 75 parts of a phenol resin (manufactured by DIC Corporation, "Phenolite TD431"), 25 parts of a melamine curing agent (manufactured by Mitsui Cyanamid Co., Ltd., "Cymel 300"), 1 part of the synthesized compounds of Examples and Comparative Examples, and 100 parts of propylene glycol monomethyl ether acetate were dissolved and filtered through a membrane filter (pore size 0.45 μm, PTFE membrane) to prepare each negative photoresist resin composition.

[0235] <Hardening Property of Exposed Part> Each of the negative-type photolithography resin compositions prepared above was applied onto a 10 cm square glass substrate using a spin coater under the conditions of 200 rpm for 10 seconds. Subsequently, after vacuum drying at 25°C for 5 minutes, it was dried on a hot plate at 100°C for 5 minutes to form a resist with a film thickness of approximately 40 μm. Ultraviolet light with a wavelength limited by L-34 (manufactured by Kenko Optics Co., Ltd., 340 nm low-pass filter) was exposed to the entire surface of this resist in a predetermined amount using an ultraviolet irradiation device (manufactured by OAK Corporation, HMW-661F-01). The integrated exposure amount was measured at a wavelength of 365 nm. Next, post-exposure baking (PEB) was performed for 10 minutes using a hot air dryer at 150°C, and then developed by immersing in a 0.5% potassium hydroxide solution for 60 seconds, followed immediately by washing with water and drying. The film thickness of this resist was measured using a shape measurement microscope (ultra-depth shape measurement microscope UK-8550, manufactured by Keyence Corporation). Here, the minimum exposure amount [mJ / cm 2 at which the change in the film thickness of the resist before and after development is within 10% was defined as the exposure part curability. The exposure part curability corresponds to the i-line sensitivity, and the lower the minimum exposure amount, the better the i-line sensitivity. The results are shown in Tables 5 and 6.

[0236]

Table 5

[0237]

Table 6

[0238] <Examples 55 to 72, Comparative Examples 3 to 8> The i-line sensitivity and KrF-line sensitivity in the positive-type photolithography resin compositions (QP-2) to (QP-4) of nonionic photoacid generators (A5, A13, A23, A33, A40, and A50), an ionic photoacid generator (A'1) for comparison, and a nonionic photoacid generator (A'2) were evaluated by the following method, and the results are shown in Tables 7 and 8.

[0239] <Evaluation of Positive-Type Photolithography Resin Compositions> <Preparation of Positive Photoresist Resin Composition (QP-2)> 10 parts of a resin having the following structural unit (m≈9) obtained by reacting 43 parts of tert-butyl methacrylate, 30 parts of methoxypolyethylene glycol methacrylate, 45 parts of methoxydiethylene glycol methacrylate, and 0.4 part of azobisisobutyronitrile under dioxane, 20 parts of a novolak resin (a co-condensate obtained by condensing m-cresol and p-cresol with formaldehyde (m-cresol / p-cresol = 40 / 60 (mass ratio), Mw = 7,000)), 1 part of the compound of Examples and Comparative Examples, and 0.03 part of N,N-dicyclohexylmethylamine were mixed and dissolved in 87 parts of propylene glycol monomethyl ether acetate, and then filtered through a membrane filter (pore size 0.45 μm, PTFE membrane) to prepare a positive photoresist resin composition (QP-2).

[0240]

Chemical formula

[0241] <Minimum exposure dose> The positive photoresist resin composition (QP-2) prepared above was spin-coated on a substrate with copper vapor-deposited on a silicon wafer, and then dried to obtain a photoresist layer. This resist layer was pre-baked on a hot plate at 110 °C for 3 minutes to obtain a coating film with a thickness of about 5 μm. Next, pattern exposure (i-line) was performed using TME-150RSC-12 (manufactured by Topcon Corporation), and post-exposure baking (PEB) was performed on a hot plate at 90 °C for 60 seconds. Then, development treatment was performed for 5 minutes by an immersion method using a 2.38 wt% aqueous solution of tetramethylammonium hydroxide, washed with running water, and blown with nitrogen to obtain a 10-μm line and space (L&S) pattern. Furthermore, the minimum exposure dose at which no residue of this pattern was observed below this value, that is, the minimum exposure dose [mJ / cm 2 required to form a resist pattern was measured. The lower the minimum exposure dose corresponding to the i-line sensitivity, the better. The results are shown in Table 7.

[0242] <Preparation of Resin Composition (QP-3) for Positive Photolithography> 35 parts of a resin having the following structural units (the numbers in the lower right of the parentheses in the structural formula represent the weight percentage of the structural units in the resin), 10 parts of a polyhydroxystyrene resin (a copolymer of p-hydroxystyrene:styrene:tert-butyl acrylate = 12:3:5, Mw = 1.0×10 4 ) and 27.5 parts of a novolak resin (a co-condensate obtained by condensing m-cresol and p-cresol with formaldehyde (m-cresol / p-cresol = 40 / 60 (mass ratio), Mw = 5,000)) and 27.5 parts of a novolak resin (a co-condensate obtained by condensing m-cresol and p-cresol with formaldehyde (m-cresol / p-cresol = 40 / 60 (mass ratio), Mw = 7,000)), 0.05 part of a surfactant (BYK310, manufactured by Big Chemie), and 1 part of the compound of the examples and comparative examples were mixed and dissolved in a mixed solvent (methoxybutyl acetate / propylene glycol monomethyl ether acetate = 60 / 40 (mass ratio)) so that the solid content concentration became 40% by weight, and then filtered through a membrane filter (pore size 0.45 μm, PTFE membrane) to prepare a resin composition (QP-3) for positive photolithography.

[0243]

Chemical formula

[0244] <Minimum Exposure Dose> After spin-coating the positive photolithography resin composition (QP-3) prepared above on a copper substrate and drying it, a photoresist layer with a thickness of about 11 μm was obtained. This resist layer was pre-baked on a hot plate at 130 °C for 5 minutes. Then, pattern exposure (i-line) was performed using TME-150RSC-12 (manufactured by Topcon Corporation), and post-exposure baking (PEB) was carried out on a hot plate at 90 °C for 90 seconds. Thereafter, an operation of dropping a 2.38 wt% aqueous solution of tetramethylammonium hydroxide onto the substrate and allowing it to stand at 23 °C for 30 seconds was performed twice, followed by washing with running water and blowing with nitrogen to obtain a 10-μm line and space (L&S) pattern. Furthermore, the minimum exposure amount at which no residue of this pattern was observed below, that is, the minimum exposure amount [mJ / cm 2 required to form a resist pattern was measured. The lower the minimum exposure amount, the better it corresponds to the i-line sensitivity. The results are shown in Table 7.

[0245]

Table 7

[0246] <Preparation of Positive Photolithography Resin Composition (QP-4)> 100 parts of a resin having the following structural units (the numbers in the lower right of the parentheses in the structural formula represent the content weight% of the structural units in the resin), 1 part of the compound of the examples and comparative examples, 0.2 part of 2-phenylbenzimidazole, and 0.1 part of a surfactant (Fujigen FTX-218, manufactured by Neos Co., Ltd.) were mixed and dissolved in 230 parts of propylene glycol monomethyl ether acetate, and then filtered through a membrane filter (pore size 0.45 μm, PTFE membrane) to prepare a positive photolithography resin composition (QP-4).

[0247]

Chemical formula

[0248] <Minimum exposure amount> On a substrate with copper vapor-deposited on a silicon wafer, the positive photolithography resin composition (QP-4) prepared above was spin-coated and then dried to obtain a photoresist layer. This resist layer was prebaked at 110 °C for 1 minute using a hot plate to obtain a coating film with a thickness of 6 μm. Next, pattern exposure (i-line) was performed using TME-150RSC-12 (manufactured by Topcon Corporation), and post-exposure baking (PEB) was performed at 90 °C for 1 minute using a hot plate. Then, development treatment was performed for 80 seconds by an immersion method using a 2.38 wt% aqueous solution of tetramethylammonium hydroxide, followed by washing with running water and blowing with nitrogen to obtain a 10-μm line and space (L&S) pattern. Furthermore, the minimum exposure amount at which no residue of this pattern was observed below that, that is, the minimum exposure amount (i-line) [mJ / cm 2 was measured. The lower the minimum exposure amount, the better it corresponds to the i-line sensitivity. The results are shown in Table 8.

[0249] <Minimum exposure amount (KrF line)> On a substrate with copper vapor-deposited on a silicon wafer, the positive photolithography resin composition (QP-4) prepared above was spin-coated and then dried to obtain a photoresist layer. This resist layer was prebaked at 110 °C for 1 minute using a hot plate to obtain a coating film with a thickness of 6 μm. Next, pattern exposure (KrF line) was performed using FPA-5000ES3 (manufactured by Canon Inc.), and post-exposure baking (PEB) was performed at 90 °C for 1 minute using a hot plate. Then, development treatment was performed for 80 seconds by an immersion method using a 2.38 wt% aqueous solution of tetramethylammonium hydroxide, followed by washing with running water and blowing with nitrogen to obtain a 10-μm line and space (L&S) pattern. Furthermore, the minimum exposure amount at which no residue of this pattern was observed below that, that is, the minimum exposure amount (KrF line) [mJ / cm 2 was measured. The lower the minimum exposure amount, the better it corresponds to the KrF line sensitivity. The results are shown in Table 8.

[0250]

Table 8

[0251] As is clear from Tables 5 to 8, the nonionic photoacid generator (A) of Examples 1 to 72 of the present invention is efficiently decomposed by i-line irradiation and exhibits high solubility in propylene glycol monomethyl ether acetate widely used in resin compositions for photolithography. Therefore, the nonionic photoacid generator (A) of the present invention is a photoacid generator excellent in i-line sensitivity and solubility in a resist solvent. Further, since the compound of the present invention efficiently generates bissulfonamide, which is a super strong acid, by i-line irradiation, the minimum exposure amount of the positive photolithography resin composition containing this is small, the curability of the exposed portion of the negative photolithography resin composition is good, and it is excellent in i-line sensitivity. Also, as is clear from Table 8, the nonionic photoacid generator (A) of the present invention is efficiently decomposed by KrF-line irradiation and generates bissulfonamide, which is a super strong acid. Therefore, the minimum exposure amount of the positive photolithography resin composition containing this is small, and since it is excellent in KrF-line sensitivity, it can be said that it is excellent in near-ultraviolet sensitivity. On the other hand, in Comparative Examples (1, 3, 5, 7) which are ionic photoacid generators, although the generated acid is bissulfonamide, the i-line decomposition rate and solubility are poor, so the photolithography resin composition containing it has poor i-line sensitivity and KrF-line sensitivity. Further, in Comparative Examples (2, 4, 6, 8) which are nonionic photoacid generators, although the i-line decomposition rate is equivalent, since the generated acid is trifluoromethanesulfonic acid, it can be seen that the photolithography resin composition containing it has low i-line and KrF-line sensitivities and poor near-ultraviolet sensitivity.

Industrial Applicability

[0252] Since the nonionic photoacid generator (A) of the present invention decomposes with high sensitivity to near-ultraviolet rays (i-line, KrF-line) and generates a super strong acid, it is useful as a photolithography material for microfabrication typified by semiconductor manufacturing.

Claims

1. A nonionic photoacid generator (A) characterized by containing a sulfonamide compound represented by the following general formula (1). 【Chemical 1】 [wherein, R ｆ is a fluorine atom, a fluoroalkyl group, or a fluoroaryl group, R １ is a fluorine atom, an alkyl group, a fluoroalkyl group, an aryl group, or a fluoroaryl group, R ｆ and R １ may be bonded to each other to form a ring, R ２ is a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a heteroatom-containing aryl group, an alkylcarbonyl group, an arylcarbonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, or an arylsulfonyl group, R ３ is a cyclic alkyl group, an aryl group, or a heteroatom-containing aryl group, R ２ and R ３ may be bonded to each other to form a ring (which may contain a heteroatom).]

2. In general formula (1), R ２ is an alkyl group having 1 to 18 carbon atoms, an aryl group having 6 to 14 carbon atoms, or a heteroatom-containing aryl group having 3 to 14 carbon atoms, and R ３ is a cyclic alkyl group having 3 to 12 carbon atoms, an aryl group having 6 to 14 carbon atoms, or a heteroatom-containing aryl group having 3 to 14 carbon atoms, and R ２ and R ３ are bonded to each other to form a 5- to 7-membered ring (which may contain a heteroatom), and the nonionic photoacid generator (A) according to claim 1.

3. In general formula (1), R ２ is an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 14 carbon atoms, a heteroatom-containing aryl group having 3 to 14 carbon atoms, an arylcarbonyl group having 6 to 10 carbon atoms (excluding the carbonyl carbon), an alkoxycarbonyl group having 1 to 10 carbon atoms (excluding the carbonyl carbon), or an alkylsulfonyl group having 1 to 10 carbon atoms, and R ３ is a cyclic alkyl group having 3 to 12 carbon atoms, an aryl group having 6 to 14 carbon atoms, or a heteroatom-containing aryl group having 3 to 14 carbon atoms. The nonionic photoacid generator (A) according to claim 1.

4. In general formula (1), R ｆ and R １ are each independently CF ３ , C ２ F ５ , C ３ F ７ , C ４ F ９ , or C ６ F ５ The nonionic photoacid generator (A) according to any one of claims 1 to 3.

5. A resin composition (Q) for photolithography containing the nonionic photoacid generator (A) according to any one of Claims 1 to 4.

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