Chemically amplified positive-type photosensitive composition, photosensitive dry film, method for producing photosensitive dry film, method for producing patterned resist film, and acid diffusion inhibitor

Abstract

To provide: a chemically amplified positive photosensitive composition that can readily form a resist pattern excelling in terms of resolution, dimensional control, and cross section rectangularity; a photosensitive dry film comprising a photosensitive layer comprising the chemically amplified positive photosensitive composition; a production method for the photosensitive dry film; a production method for a patterned resist film using the chemically amplified positive photosensitive composition; and an acid diffusion inhibitor to be blended in the chemically amplified positive photosensitive composition.SOLUTION: A chemically amplified positive photosensitive composition contains an acid generator (A) that generates acid upon irradiation with active rays or radiation and a resin (B) that has alkali solubility to increase by the action of an acid, and is further blended with an acid diffusion inhibitor (C) of a specific structure.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a chemically amplified positive-type photosensitive composition, a photosensitive dry film having a photosensitive layer made of the chemically amplified positive-type photosensitive composition, a method for producing the photosensitive dry film, a method for producing a patterned resist film using the aforementioned chemically amplified positive-type photosensitive composition, and an acid diffusion inhibitor. [Background technology]

[0002] At present, photofabrication is the mainstream of precision micromachining technology. Photofabrication is a general term for a technology in which a photoresist composition is applied to the surface of a workpiece to form a photoresist layer, the photoresist layer is patterned by photolithography technology, and the patterned photoresist layer (photoresist pattern) is used as a mask to perform chemical etching, electrolytic etching, or electroforming mainly involving electroplating, to manufacture various precision parts such as semiconductor packages.

[0003] In recent years, with the downsizing of electronic devices, high-density mounting technology for semiconductor packages has advanced, with efforts being made to increase the mounting density by implementing multi-pin thin-film mounting of packages, miniaturizing package size, and using two-dimensional mounting technology and three-dimensional mounting technology with the flip chip method. In such high-density mounting technology, for example, protruding electrodes (mounting terminals) such as bumps protruding from the package, and metal posts that connect rewiring extending from peripheral terminals on the wafer to the mounting terminals are arranged with high precision on the substrate as connection terminals.

[0004] Photoresist compositions are used in the above-mentioned photofabrication, and chemically amplified photosensitive compositions containing an acid generator are known as such photoresist compositions (see Patent Documents 1 and 2, etc.). In chemically amplified photosensitive compositions, an acid is generated from an acid generator upon irradiation (exposure), and diffusion of the acid is promoted by heat treatment, causing an acid-catalyzed reaction with the base resin in the composition, etc., and changing its alkali solubility.

[0005] Such chemically amplified photosensitive compositions are used for forming patterned insulating films and etching masks, as well as for forming plated objects such as bumps, metal posts, and Cu rewiring by plating processes. Specifically, a photoresist layer of a desired thickness is formed on a support such as a metal substrate using the chemically amplified photosensitive composition, and exposed through a predetermined mask pattern, and developed to form a photoresist pattern used as a mold in which the portion forming the plated object is selectively removed (peeled off). Then, a conductor such as copper is embedded in the removed portion (non-resist portion) by plating, and then the photoresist pattern around it is removed to form bumps, metal posts, and Cu rewiring. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 9-176112 [Patent Document 2] Japanese Patent Application Publication No. 11-52562 Summary of the Invention [Problem to be solved by the invention]

[0007] As semiconductor packages become increasingly dense, there is a demand for even higher density and precision protruding electrodes, metal posts, etc. In order to realize even higher density and precision protruding electrodes, metal posts, etc., a chemically amplified photosensitive composition capable of forming a resist pattern having high resolution and dimensional controllability and excellent rectangularity in cross-sectional shape is desired.

[0008] However, when using a conventional chemically amplified resist composition such as those disclosed in Patent Documents 1 and 2, the resolution and dimensional controllability are insufficient, and it is often difficult to form a resist pattern with a good rectangular cross-sectional shape. For example, when using a conventional chemically amplified resist composition, the resist portion may overhang the non-resist portion near the contact surface (interface) between the substrate surface and the resist pattern, resulting in a footing shape (a skirting shape), or a bite shape that is the opposite of a footing shape, and the verticality of the cross-sectional shape may be poor, making it impossible to obtain a resist pattern with a rectangular cross-sectional shape.

[0009] The present invention has been made in consideration of the above-mentioned problems, and has an object to provide a chemically amplified positive-type photosensitive composition that is capable of easily forming a resist pattern having high resolution and dimensional controllability and good rectangularity in cross-sectional shape, a photosensitive dry film having a photosensitive layer made of the chemically amplified positive-type photosensitive composition, a method for producing the photosensitive dry film, a method for producing a patterned resist film using the aforementioned chemically amplified positive-type photosensitive composition, and an acid diffusion inhibitor to be blended in the chemically amplified positive-type photosensitive composition. [Means for solving the problem]

[0010] As a result of intensive research into achieving the above object, the present inventors have found that the above problems can be solved by blending an acid diffusion inhibitor (C) having a specific structure with a chemically amplified positive photosensitive composition containing an acid generator (A) that generates an acid when irradiated with actinic rays or radiation, and a resin (B) whose solubility in alkali increases under the action of an acid, and have thus completed the present invention. Specifically, the present invention provides the following.

[0011] A first aspect of the present invention is a composition comprising an acid generator (A) that generates an acid upon exposure to actinic rays or radiation, a resin (B) whose solubility in alkali increases under the action of the acid, and an acid diffusion inhibitor (C), The chemically amplified positive-working photosensitive composition contains an acid diffusion inhibitor (C) that contains a compound represented by the following formula (C1). [ka] (In formula (C1), R 1c is an alkyl group or an aralkyl group, R 2c is an alkyl group or an aralkyl group, R 3c is a hydrogen atom or an alkyl group, R 4c is a single bond or an alkylene group, n1 is an integer between 0 and 5, n2 is an integer between 0 and 5, n3 is 0 or 1. However, when n3 is 1, n1 and n2 cannot be 0 at the same time.)

[0012] A second aspect of the present invention is a photosensitive dry film having a base film and a photosensitive layer formed on the surface of the base film, the photosensitive layer being made of the chemically amplified photosensitive composition according to the first aspect.

[0013] A third aspect of the present invention is a method for producing a photosensitive dry film, comprising applying the chemically amplified positive-type photosensitive composition according to the first aspect onto a substrate film to form a photosensitive layer.

[0014] A fourth aspect of the present invention is A lamination step of laminating a photosensitive layer made of the chemically amplified positive-type photosensitive composition according to the first embodiment on a substrate; an exposure step of exposing the photosensitive layer to actinic rays or radiation in a position-selective manner; and a developing step of developing the photosensitive layer after exposure.

[0015] A fifth aspect of the present invention is an acid diffusion inhibitor to be blended in a chemically amplified positive-working photosensitive composition, the acid diffusion inhibitor comprising: an acid generator (A) that generates an acid upon exposure to actinic rays or radiation; and a resin (B) whose solubility in alkali increases under the action of an acid, the acid diffusion inhibitor comprising: The acid diffusion inhibitor comprises a compound represented by the following formula (C1). [ka] (In formula (C1), R 1c is an alkyl group or an aralkyl group, R 2c is an alkyl group or an aralkyl group, R 3c is a hydrogen atom or an alkyl group, R 4c is a single bond or an alkylene group, n1 is an integer between 0 and 5, n2 is an integer between 0 and 5, n3 is 0 or 1. However, when n3 is 1, n1 and n2 cannot be 0 at the same time.) Effect of the Invention

[0016] According to the present invention, it is possible to provide a chemically amplified positive-type photosensitive composition that is capable of easily forming a resist pattern having high resolution and dimensional controllability and good rectangularity in cross-sectional shape, a photosensitive dry film having a photosensitive layer made of the chemically amplified positive-type photosensitive composition, a method for producing the photosensitive dry film, a method for producing a patterned resist film using the aforementioned chemically amplified positive-type photosensitive composition, and an acid diffusion inhibitor that is blended in the chemically amplified positive-type photosensitive composition. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] <Chemically amplified positive-type photosensitive composition> The chemically amplified positive-type photosensitive composition (hereinafter also referred to as the photosensitive composition) contains an acid generator (A) (hereinafter also referred to as the acid generator (A)) that generates an acid when exposed to actinic rays or radiation, a resin (B) (hereinafter also referred to as the resin (B)) whose solubility in alkali increases due to the action of the acid, and an acid diffusion inhibitor (C). The acid diffusion inhibitor (C) has a specific structure, as described below. The photosensitive composition may contain components such as an alkali-soluble resin (D), a sulfur-containing compound (E), and an organic solvent (S) as necessary.

[0018] <Acid Generator (A)> The acid generator (A) is a compound that generates an acid by irradiation with actinic rays or radiation, and is not particularly limited as long as it is a compound that generates an acid directly or indirectly by light. The acid generator (A) is preferably an acid generator of the first to fifth aspects described below. Hereinafter, preferred ones of the acid generators (A) that are preferably used in the photosensitive composition will be described as the first to fifth aspects.

[0019] A first embodiment of the acid generator (A) is a compound represented by the following formula (a1).

[0020] [ka]

[0021] In the above formula (a1), X 1a represents a sulfur atom or an iodine atom with a valence of g, where g is 1 or 2. h represents the number of repeating units of the structure in parentheses. R 1a X 1a an aryl group having 6 to 30 carbon atoms, a heterocyclic group having 4 to 30 carbon atoms, an alkyl group having 1 to 30 carbon atoms, an alkenyl group having 2 to 30 carbon atoms, or an alkynyl group having 2 to 30 carbon atoms; R 1aR may be substituted with at least one selected from the group consisting of alkyl, hydroxy, alkoxy, alkylcarbonyl, arylcarbonyl, alkoxycarbonyl, aryloxycarbonyl, arylthiocarbonyl, acyloxy, arylthio, alkylthio, aryl, heterocyclic, aryloxy, alkylsulfinyl, arylsulfinyl, alkylsulfonyl, arylsulfonyl, alkyleneoxy, amino, cyano, nitro, and halogen. 1a The number of is g+h(g-1)+1, and R 1a may be the same or different from each other. 1a are directly connected to each other, or -O-, -S-, -SO-, -SO2-, -NH-, -NR 2a -, -CO-, -COO-, -CONH-, an alkylene group having 1 to 3 carbon atoms, or a phenylene group; 1a R 2a is an alkyl group having from 1 to 5 and more than 1 carbon atoms, or an aryl group having from 6 to 10 and more than 1 carbon atoms.

[0022] X 2a is a structure represented by the following formula (a2).

[0023] [ka]

[0024] In the above formula (a2), X 4a represents an alkylene group having 1 to 8 carbon atoms, an arylene group having 6 to 20 carbon atoms, or a divalent group of a heterocyclic compound having 8 to 20 carbon atoms; X 4a X may be substituted with at least one selected from the group consisting of alkyl having 1 to 8 carbon atoms, alkoxy having 1 to 8 carbon atoms, aryl having 6 to 10 carbon atoms, hydroxy, cyano, nitro, and halogen. 5a -O-, -S-, -SO-, -SO2-, -NH-, -NR 2a-, -CO-, -COO-, -CONH-, an alkylene group having 1 to 3 carbon atoms, or a phenylene group. h represents the number of repeating units of the structure in parentheses. h+1 X 4a and h X's 5a may be the same or different. 2a is as defined above.

[0025] X 3a- is a counter ion of the onium, and examples thereof include a fluorinated alkylfluorophosphate anion represented by the following formula (a17) or a borate anion represented by the following formula (a18).

[0026] [ka]

[0027] In the above formula (a17), R 3a represents an alkyl group in which 80% or more of the hydrogen atoms are substituted with fluorine atoms. j represents the number of R 3a may be the same or different.

[0028] [ka]

[0029] In the above formula (a18), R 4a ~R 7a each independently represents a fluorine atom or a phenyl group, and some or all of the hydrogen atoms of the phenyl group may be substituted with at least one selected from the group consisting of a fluorine atom and a trifluoromethyl group.

[0030] Examples of the onium ion in the compound represented by the above formula (a1) include triphenylsulfonium, tri-p-tolylsulfonium, 4-(phenylthio)phenyldiphenylsulfonium, bis[4-(diphenylsulfonio)phenyl]sulfide, bis[4-{bis[4-(2-hydroxyethoxy)phenyl]sulfonio}phenyl]sulfide, bis{4-[bis(4-fluorophenyl)sulfonio]phenyl}sulfide, 4-(4-benzoyl-2-chlorophenylthio)phenylbis (4-Fluorophenyl)sulfonium, 7-isopropyl-9-oxo-10-thia-9,10-dihydroanthracen-2-yldi-p-tolylsulfonium, 7-isopropyl-9-oxo-10-thia-9,10-dihydroanthracen-2-yldiphenylsulfonium, 2-[(diphenyl)sulfonio]thioxanthone, 4-[4-(4-tert-butylbenzoyl)phenylthio]phenyldi-p-tolylsulfonium, 4-(4-benzoylphenylthio)phenyldiphenyl sulfonium, diphenylphenacylsulfonium, 4-hydroxyphenylmethylbenzylsulfonium, 2-naphthylmethyl(1-ethoxycarbonyl)ethylsulfonium, 4-hydroxyphenylmethylphenacylsulfonium, phenyl[4-(4-biphenylthio)phenyl]4-biphenylsulfonium, phenyl[4-(4-biphenylthio)phenyl]3-biphenylsulfonium, [4-(4-acetophenylthio)phenyl]diphenylsulfonium, octadecylmethylphenacylsulfonium, diphenyliodonium, di-p-tolyliodonium, bis(4-dodecylphenyl)iodonium, bis(4-methoxyphenyl)iodonium, (4-octyloxyphenyl)phenyliodonium, bis(4-decyloxy)phenyliodonium, 4-(2-hydroxytetradecyloxy)phenylphenyliodonium, 4-isopropylphenyl(p-tolyl)iodonium, or 4-isobutylphenyl(p-tolyl)iodonium.

[0031] Of the onium ions in the compound represented by the above formula (a1), preferred onium ions include the sulfonium ion represented by the following formula (a19).

[0032] [ka]

[0033] In the above formula (a19), R 8a Each of X independently represents a group selected from the group consisting of a hydrogen atom, an alkyl group, a hydroxy group, an alkoxy group, an alkylcarbonyl group, an alkylcarbonyloxy group, an alkyloxycarbonyl group, a halogen atom, an aryl group which may have a substituent, and an arylcarbonyl group which may have a substituent. 2a is X in the above formula (a1). 2a It has the same meaning as:

[0034] Specific examples of the sulfonium ion represented by the above formula (a19) include 4-(phenylthio)phenyldiphenylsulfonium, 4-(4-benzoyl-2-chlorophenylthio)phenylbis(4-fluorophenyl)sulfonium, 4-(4-benzoylphenylthio)phenyldiphenylsulfonium, phenyl[4-(4-biphenylthio)phenyl]4-biphenylsulfonium, phenyl[4-(4-biphenylthio)phenyl]3-biphenylsulfonium, [4-(4-acetophenylthio)phenyl]diphenylsulfonium, and diphenyl[4-(p-terphenylthio)phenyl]diphenylsulfonium.

[0035] In the fluorinated alkyl fluorophosphate anion represented by the above formula (a17), R 3arepresents an alkyl group substituted with a fluorine atom, the number of carbon atoms being preferably 1 or more and 8 or less, more preferably 1 or more and 4 or less. Specific examples of the alkyl group include linear alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, and octyl; branched alkyl groups such as isopropyl, isobutyl, sec-butyl, and tert-butyl; and cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl. The ratio of hydrogen atoms in the alkyl group substituted with fluorine atoms is usually 80% or more, preferably 90% or more, and more preferably 100%. If the substitution rate of fluorine atoms is less than 80%, the acid strength of the onium fluorinated alkyl fluorophosphate represented by the above formula (a1) is reduced.

[0036] Particularly preferred R 3a R is a linear or branched perfluoroalkyl group having 1 to 4 carbon atoms and a fluorine atom substitution rate of 100%, and specific examples include CF3, CF3CF2, (CF3)2CF, CF3CF2CF2, CF3CF2CF2CF2, (CF3)2CFCF2, CF3CF2(CF3)CF, and (CF3)3C. 3a The number j is an integer of 1 or more and 5 or less, preferably 2 or more and 4 or less, and particularly preferably 2 or 3.

[0037] A specific example of a preferred fluorinated alkyl fluorophosphate anion is [(CF3CF2)2PF4] - , [(CF3CF2)3PF3] - , [((CF3)2CF)2PF4] - , [((CF3)2CF)3PF3] - , [(CF3CF2CF2)2PF4] - , [(CF3CF2CF2)3PF3] - , [((CF3)2CFCF2)2PF4] - , [((CF3)2CFCF2)3PF3] - , [(CF3CF2CF2CF2)2PF4] - , or [(CF3CF2CF2)3PF3] - Among these, [(CF3CF2)3PF3]- , [(CF3CF2CF2)3PF3] - , [((CF3)2CF)3PF3] - , [((CF3)2CF)2PF4] - , [((CF3)2CFCF2)3PF3] - , or [((CF3)2CFCF2)2PF4] - is particularly preferred.

[0038] A preferred example of the borate anion represented by the above formula (a18) is tetrakis(pentafluorophenyl)borate ([B(C6F5)4] - ), tetrakis[(trifluoromethyl)phenyl]borate ([B(C6H4CF3)4] - ), difluorobis(pentafluorophenyl)borate ([(C6F5)2BF2] - ), trifluoro(pentafluorophenyl)borate ([(C6F5)BF3] - ), tetrakis(difluorophenyl)borate ([B(C6H3F2)4] - Among these, tetrakis(pentafluorophenyl)borate ([B(C6F5)4] - ) is particularly preferred.

[0039] As a second embodiment of the acid generator (A), 2,4-bis(trichloromethyl)-6-piperonyl-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-[2-(2-furyl)ethenyl]-s-triazine, 2,4-bis(trichloromethyl)-6-[2-(5-methyl-2-furyl)ethenyl]-s-triazine, 2,4-bis(trichloromethyl)-6-[2-(5-ethyl-2-furyl)ethenyl]-s-triazine, 2,4-bis(trichloromethyl)-6-[2-(5-propyl-2-furyl)ethenyl]-s-triazine, 2,4-bis(trichloromethyl)-6-[2-(3,5-dimethoxyphenyl)ethenyl]-s-triazine, 2,4-bis(trichloromethyl)-6-[2-(3,5-diethoxyphenyl)ethenyl]-s-triazine, 2,4-bis(trichloromethyl)-6-[2-(3,5-dipropoxyphenyl)ethenyl]-s-triazine, 2,4-bis(trichloromethyl)-6-[2-(3-methoxy-5-ethoxyphenyl)ethenyl]-s-triazine, 2,4-bis(trichloromethyl)-6-[2-(3-methoxy-5-propoxyphenyl)ethenyl]-s-triazine )ethenyl]-s-triazine, 2,4-bis(trichloromethyl)-6-[2-(3,4-methylenedioxyphenyl)ethenyl]-s-triazine, 2,4-bis(trichloromethyl)-6-(3,4-methylenedioxyphenyl)-s-triazine, 2,4-bis-trichloromethyl-6-(3-bromo-4-methoxy)phenyl-s-triazine, 2,4-bis-trichloromethyl-6-(2-bromo-4-methoxy)phenyl-s-triazine, 2,4-bis-trichloromethyl-6-(2-bromo-4-methoxy)styrylphenyl-s-triazine riazine, 2,4-bis-trichloromethyl-6-(3-bromo-4-methoxy)styrylphenyl-s-triazine, 2-(4-methoxyphenyl)-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-(4-methoxynaphthyl)-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-[2-(2-furyl)ethenyl]-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-[2-(3,5-dimethoxyphenyl)ethenyl]-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-[2-(3,4-dimethoxyphenyl)ethenyl]-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-(3,4-methylenedioxyphenyl)-4,6-bis(trichloromethyl)-1,3,5-triazine, tris(1,3-dibromopropyl)-1,3,5-triazine, tris(2,3-dibromopropyl)-1,3,5-triazine, and halogen-containing triazine compounds represented by the following formula (a3), such as tris(2,3-dibromopropyl)isocyanurate, are included.

[0040] [ka]

[0041] In the above formula (a3), R 9a , R 10a , R 11a each independently represents a halogenated alkyl group.

[0042] Furthermore, examples of a third embodiment of the acid generator (A) include α-(p-toluenesulfonyloxyimino)-phenylacetonitrile, α-(benzenesulfonyloxyimino)-2,4-dichlorophenylacetonitrile, α-(benzenesulfonyloxyimino)-2,6-dichlorophenylacetonitrile, α-(2-chlorobenzenesulfonyloxyimino)-4-methoxyphenylacetonitrile, α-(ethylsulfonyloxyimino)-1-cyclopentenylacetonitrile, and a compound represented by the following formula (a4) containing an oxime sulfonate group.

[0043] [ka]

[0044] In the above formula (a4), R 12a represents a monovalent, divalent, or trivalent organic group; R 13arepresents a substituted or unsubstituted saturated hydrocarbon group, unsaturated hydrocarbon group, or aromatic group, and n represents the number of repeating units of the structure in the parentheses.

[0045] In the above formula (a4), examples of the aromatic group include aryl groups such as phenyl and naphthyl groups, and heteroaryl groups such as furyl and thienyl groups. These may have one or more suitable substituents on the ring, such as halogen atoms, alkyl groups, alkoxy groups, and nitro groups. 13a is particularly preferably an alkyl group having 1 to 6 carbon atoms, such as a methyl group, an ethyl group, a propyl group, and a butyl group. 12a is an aromatic group, and R 13a is an alkyl group having 1 to 4 carbon atoms.

[0046] The acid generator represented by the above formula (a4) is, when n=1, R 12a is a phenyl group, a methylphenyl group, or a methoxyphenyl group, and R 13a is a methyl group, specifically, α-(methylsulfonyloxyimino)-1-phenylacetonitrile, α-(methylsulfonyloxyimino)-1-(p-methylphenyl)acetonitrile, α-(methylsulfonyloxyimino)-1-(p-methoxyphenyl)acetonitrile, [2-(propylsulfonyloxyimino)-2,3-dihydroxythiophen-3-ylidene](o-tolyl)acetonitrile, etc. When n=2, specific examples of the acid generator represented by the above formula (a4) include acid generators represented by the following formula:

[0047] [ka]

[0048] A fourth embodiment of the acid generator (A) is an onium salt having a naphthalene ring in the cation portion. The term "having a naphthalene ring" means that the structure is derived from naphthalene, and that at least two ring structures and their aromaticity are maintained. The naphthalene ring may have a substituent such as a linear or branched alkyl group having 1 to 6 carbon atoms, a hydroxyl group, or a linear or branched alkoxy group having 1 to 6 carbon atoms. The structure derived from the naphthalene ring may be a monovalent group (having one free valence) or a divalent group (having two or more free valences), but is preferably a monovalent group (however, in this case, the free valence is counted excluding the portion bonded to the above-mentioned substituent). The number of naphthalene rings is preferably 1 to 3.

[0049] The cation moiety of such an onium salt having a naphthalene ring at the cation moiety is preferably a structure represented by the following formula (a5).

[0050] [ka]

[0051] In the above formula (a5), R 14a , R 15a , R 16a At least one of R represents a group represented by the following formula (a6), and the rest represent a linear or branched alkyl group having 1 to 6 carbon atoms, a phenyl group which may have a substituent, a hydroxyl group, or a linear or branched alkoxy group having 1 to 6 carbon atoms. 14a , R 15a , R 16a one of them is a group represented by the following formula (a6), and the remaining two are each independently a linear or branched alkylene group having from 1 to 6 carbon atoms, and the ends of these may be bonded to form a ring.

[0052] [ka]

[0053] In the above formula (a6), R 17a , R 18a each independently represents a hydroxyl group, a linear or branched alkoxy group having from 1 to 6 carbon atoms, or a linear or branched alkyl group having from 1 to 6 carbon atoms; R 19a represents a single bond or a linear or branched alkylene group having 1 to 6 carbon atoms which may have a substituent. l and m each independently represent an integer of 0 to 2, and l+m is 3 or less. 17a When there are multiple R, they may be the same or different. 18a When multiple are present, they may be the same or different.

[0054] Above R 14a , R 15a , R 16a Among these, the number of groups represented by the above formula (a6) is preferably one from the viewpoint of the stability of the compound, and the rest are linear or branched alkylene groups having 1 to 6 carbon atoms, the ends of which may be bonded to form a ring. In this case, the above two alkylene groups form a 3- to 9-membered ring including the sulfur atom. The number of atoms (including the sulfur atom) constituting the ring is preferably 5 to 6.

[0055] Furthermore, examples of the substituent that the alkylene group may have include an oxygen atom (which in this case forms a carbonyl group together with the carbon atom that constitutes the alkylene group) and a hydroxyl group.

[0056] In addition, examples of the substituent that the phenyl group may have include a hydroxyl group, a linear or branched alkoxy group having 1 to 6 carbon atoms, and a linear or branched alkyl group having 1 to 6 carbon atoms.

[0057] As these cationic moieties, those represented by the following formulae (a7) and (a8) can be mentioned, and the structure represented by the following formula (a8) is particularly preferred.

[0058] [ka]

[0059] Such a cationic moiety may be either an iodonium salt or a sulfonium salt, but from the standpoint of acid generation efficiency and the like, a sulfonium salt is preferred.

[0060] Therefore, the anion moiety of an onium salt having a naphthalene ring in the cation moiety is preferably an anion capable of forming a sulfonium salt.

[0061] The anion portion of such an acid generator is a fluoroalkylsulfonate ion or an arylsulfonate ion in which some or all of the hydrogen atoms have been fluorinated.

[0062] The alkyl group in the fluoroalkylsulfonate ion may be linear, branched, or cyclic and have 1 to 20 carbon atoms, and preferably has 1 to 10 carbon atoms in view of the bulkiness of the generated acid and its diffusion distance. In particular, branched or cyclic groups are preferred because they have a short diffusion distance. In addition, preferred groups include methyl, ethyl, propyl, butyl, and octyl groups because they can be synthesized at low cost.

[0063] The aryl group in the arylsulfonate ion is an aryl group having 6 to 20 carbon atoms, and examples thereof include an alkyl group, a phenyl group which may or may not be substituted with a halogen atom, and a naphthyl group. In particular, an aryl group having 6 to 10 carbon atoms is preferred because it can be synthesized at low cost. Specific examples of preferred groups include a phenyl group, a toluenesulfonyl group, an ethylphenyl group, a naphthyl group, and a methylnaphthyl group.

[0064] In the above-mentioned fluoroalkylsulfonate ion or arylsulfonate ion, when some or all of the hydrogen atoms are fluorinated, the fluorination rate is preferably 10% or more and 100% or less, more preferably 50% or more and 100% or less, and in particular, those in which all the hydrogen atoms are replaced with fluorine atoms are preferred because they have a stronger acid strength.Specific examples of such ions include trifluoromethanesulfonate, perfluorobutanesulfonate, perfluorooctane sulfonate, and perfluorobenzenesulfonate.

[0065] Among these, preferred anion moieties include those represented by the following formula (a9).

[0066] [ka]

[0067] In the above formula (a9), R 20a are groups represented by the following formulae (a10), (a11), and (a12).

[0068] [ka]

[0069] In the above formula (a10), x represents an integer of 1 or more and 4 or less. In addition, in the above formula (a11), R 21a represents a hydrogen atom, a hydroxyl group, a linear or branched alkyl group having from 1 to 6 carbon atoms, or a linear or branched alkoxy group having from 1 to 6 carbon atoms, and y represents an integer of from 1 to 3. Among these, trifluoromethanesulfonate and perfluorobutanesulfonate are preferred from the viewpoint of safety.

[0070] The anion moiety may also contain nitrogen and be represented by the following formulae (a13) and (a14).

[0071] [ka]

[0072] In the above formulas (a13) and (a14), X a represents a linear or branched alkylene group in which at least one hydrogen atom is substituted with a fluorine atom, and the alkylene group has 2 to 6 carbon atoms, preferably 3 to 5 carbon atoms, and most preferably 3 carbon atoms. a , Z a each independently represents a linear or branched alkyl group in which at least one hydrogen atom is substituted with a fluorine atom, and the alkyl group has 1 or more and 10 or less carbon atoms, preferably 1 or more and 7 or less, and more preferably 1 or more and 3 or less carbon atoms.

[0073] X a The number of carbon atoms in the alkylene group, or Y a , Z a The smaller the number of carbon atoms in the alkyl group, the better the solubility in organic solvents, and therefore the more preferable.

[0074] Also, X a or an alkylene group of Y a , Z a In the alkyl group, the more hydrogen atoms substituted with fluorine atoms, the stronger the acid strength, which is preferable. The ratio of fluorine atoms in the alkylene group or alkyl group, i.e., the fluorination rate, is preferably 70% or more and 100% or less, more preferably 90% or more and 100% or less, and most preferably a perfluoroalkylene group or perfluoroalkyl group in which all hydrogen atoms are substituted with fluorine atoms.

[0075] Preferable onium salts having a naphthalene ring in the cation moiety include compounds represented by the following formulae (a15) and (a16).

[0076] [ka]

[0077] Further, as a fifth embodiment of the acid generator (A), there may be mentioned bissulfonyldiazomethanes such as bis(p-toluenesulfonyl)diazomethane, bis(1,1-dimethylethylsulfonyl)diazomethane, bis(cyclohexylsulfonyl)diazomethane, and bis(2,4-dimethylphenylsulfonyl)diazomethane; nitrobenzyl derivatives such as 2-nitrobenzyl p-toluenesulfonate, 2,6-dinitrobenzyl p-toluenesulfonate, nitrobenzyl tosylate, dinitrobenzyl tosylate, nitrobenzyl sulfonate, nitrobenzyl carbonate, and dinitrobenzyl carbonate; sulfonic acid esters such as pyrogallol trimesylate, pyrogallol tritosylate, benzyl tosylate, benzyl sulfonate, N-methylsulfonyloxysuccinimide, N-trichloromethylsulfonyloxysuccinimide, N-phenylsulfonyloxymaleimide, and N-methylsulfonyloxyphthalimide; trifluoromethanesulfonic acid esters such as N-(trifluoromethylsulfonyloxy)phthalimide, N-(trifluoromethylsulfonyloxy)-1,8-naphthalimide, and N-(trifluoromethylsulfonyloxy)-4-butyl-1,8-naphthalimide; onium salts such as diphenyliodonium hexafluorophosphate, (4-methoxyphenyl)phenyliodonium trifluoromethanesulfonate, bis(p-tert-butylphenyl)iodonium trifluoromethanesulfonate, triphenylsulfonium hexafluorophosphate, (4-methoxyphenyl)diphenylsulfonium trifluoromethanesulfonate, and (p-tert-butylphenyl)diphenylsulfonium trifluoromethanesulfonate; benzoin tosylate, benzoin tosylates such as α-methylbenzoin tosylate; and other diphenyliodonium salts, triphenylsulfonium salts, phenyldiazonium salts, and benzyl carbonate.

[0078] As the acid generator (A), a naphthalic acid derivative represented by the following formula (a21) is also preferred. [ka] (In formula (a21), R 22a is a monovalent organic group, R 23a , R 24a , R 25a , and R 26a are each independently a hydrogen atom or a monovalent organic group, R 23a and R 24a And, R 24a and R 25a and, or R 25a and R 26a may be bonded to each other to form a ring.

[0079] R 22a The organic group as the aryl group is not particularly limited as long as it does not impair the object of the present invention. The organic group may be a hydrocarbon group, or may contain a heteroatom such as O, N, S, P, or a halogen atom. The structure of the organic group may be linear, branched, cyclic, or a combination of these structures.

[0080] R 22a Suitable organic groups for the aryl group include an aliphatic hydrocarbon group having from 1 to 18 carbon atoms which may be substituted with a halogen atom and / or an alkylthio group, an aryl group having from 6 to 20 carbon atoms which may have a substituent, an aralkyl group having from 7 to 20 carbon atoms which may have a substituent, an alkylaryl group having from 7 to 20 carbon atoms which may have a substituent, a camphor-10-yl group, and a group represented by the following formula (a21a): -R 27a -(O) a -R 28a -(O) b -Y 1 -R 29a (a21a) (In formula (a21a), Y 1 R is a single bond or an alkanediyl group having 1 to 4 carbon atoms. 27a and R 28a R is an alkanediyl group having 2 to 6 carbon atoms which may be substituted with a halogen atom, or an arylene group having 6 to 20 carbon atoms which may be substituted with a halogen atom. 29ais an alkyl group having 1 to 18 carbon atoms which may be substituted with a halogen atom, an alicyclic hydrocarbon group having 3 to 12 carbon atoms, an aryl group having 6 to 20 carbon atoms which may be substituted with a halogen atom, or an aralkyl group having 7 to 20 carbon atoms which may be substituted with a halogen atom. a and b each are 0 or 1, and at least one of a and b is 1. Examples of the group include a group represented by the following formula:

[0081] R 22a When the organic group has a halogen atom as a substituent, examples of the halogen atom include a chlorine atom, a bromine atom, an iodine atom, and a fluorine atom.

[0082] R 22a When the organic group represented by the formula (I) is an alkyl group having 1 to 18 carbon atoms substituted with an alkylthio group, the alkylthio group preferably has 1 to 18 carbon atoms. Examples of the alkylthio group having 1 to 18 carbon atoms include a methylthio group, an ethylthio group, an n-propylthio group, an isopropylthio group, an n-butylthio group, a sec-butylthio group, a tert-butylthio group, an isobutylthio group, an n-pentylthio group, an isopentylthio group, a tert-pentylthio group, an n-hexylthio group, an n-heptylthio group, an isoheptylthio group, a tert-heptylthio group, an n-octylthio group, an isooctylthio group, a tert-octylthio group, a 2-ethylhexylthio group, an n-nonylthio group, an n-decylthio group, an n-undecylthio group, an n-dodecylthio group, an n-tridecylthio group, an n-tetradecylthio group, an n-pentadecylthio group, an n-hexadecylthio group, an n-heptadecylthio group, and an n-octadecylthio group.

[0083] R 22a When the organic group as represented by is an aliphatic hydrocarbon group having from 1 to 18 carbon atoms which may be substituted with a halogen atom and / or an alkylthio group, the aliphatic hydrocarbon group may contain an unsaturated double bond. The structure of the aliphatic hydrocarbon group is not particularly limited, and may be linear, branched, or cyclic, or may be a combination of these structures.

[0084] R 22a When the organic group as the alkyl group is an alkenyl group, preferred examples thereof include an allyl group and a 2-methyl-2-propenyl group.

[0085] R 22a Preferred examples of the organic group as an alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, an isobutyl group, an n-pentyl group, an isopentyl group, a tert-pentyl group, an n-hexyl group, an n-hexane-2-yl group, an n-hexane-3-yl group, an n-heptyl group, an n-heptan-2-yl group, an n-heptan-3-yl group, an isoheptyl group, a tert-heptyl group, an n-octyl group, an isooctyl group, a tert-octyl group, a 2-ethylhexyl group, an n-nonyl group, an isononyl group, an n-decyl group, an n-undecyl group, an n-dodecyl group, an n-tridecyl group, an n-tetradecyl group, an n-pentadecyl group, an n-hexadecyl group, an n-heptadecyl group, and an n-octadecyl group.

[0086] R 22a When the organic group as is an alicyclic hydrocarbon group, examples of the alicyclic hydrocarbon constituting the main skeleton of the alicyclic hydrocarbon group include cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, cyclodecane, bicyclo[2.1.1]hexane, bicyclo[2.2.1]heptane, bicyclo[3.2.1]octane, bicyclo[2.2.2]octane, and adamantane. As the alicyclic hydrocarbon group, a group in which one hydrogen atom has been removed from these alicyclic hydrocarbons is preferable.

[0087] R 22aPreferred examples of the organic group as an aliphatic hydrocarbon group substituted with a halogen atom include a trifluoromethyl group, a pentafluoroethyl group, a 2-chloroethyl group, a 2-bromoethyl group, a heptafluoro-n-propyl group, a 3-bromopropyl group, a nonafluoro-n-butyl group, a tridecafluoro-n-hexyl group, a heptadecafluoro-n-octyl group, a 2,2,2-trifluoroethyl group, a 1,1-difluoroethyl group, a 1,1-difluoro-n-propyl group, a 1,1,2,2-tetrafluoro-n-propyl group, a 3,3,3-trifluoro-n-propyl group, a 2,2,3,3,3-pentafluoro-n-propyl group, a 2-norbornyl-1,1-difluoroethyl group, a 2-norbornyltetrafluoroethyl group, and a 3-adamantyl-1,1,2,2-tetrafluoropropyl group.

[0088] R 22a When the organic group as the alkylthio group is an aliphatic hydrocarbon group substituted with an alkylthio group, preferred examples thereof include a 2-methylthioethyl group, a 4-methylthio-n-butyl group, and a 2-n-butylthioethyl group.

[0089] R 22a When the organic group as is an aliphatic hydrocarbon group substituted with a halogen atom and an alkylthio group, a suitable example thereof is a 3-methylthio-1,1,2,2-tetrafluoro-n-propyl group.

[0090] R 22a When the organic group as the alkyl group is an aryl group, preferred examples thereof include a phenyl group, a naphthyl group, and a biphenylyl group.

[0091] R 22a When the organic group as is an aryl group substituted with a halogen atom, preferred examples thereof include a pentafluorophenyl group, a chlorophenyl group, a dichlorophenyl group, and a trichlorophenyl group.

[0092] R 22aWhen the organic group as the alkylthio group is an aryl group substituted with an alkylthio group, preferred examples thereof include a 4-methylthiophenyl group, a 4-n-butylthiophenyl group, a 4-n-octylthiophenyl group, and a 4-n-dodecylthiophenyl group.

[0093] R 22a When the organic group as the alkyl group is an aryl group substituted with a halogen atom and an alkylthio group, preferred examples thereof include a 1,2,5,6-tetrafluoro-4-methylthiophenyl group, a 1,2,5,6-tetrafluoro-4-n-butylthiophenyl group, and a 1,2,5,6-tetrafluoro-4-n-dodecylthiophenyl group.

[0094] R 22a When the organic group as the alkyl group is an aralkyl group, preferred examples thereof include a benzyl group, a phenethyl group, a 2-phenylpropan-2-yl group, a diphenylmethyl group, and a triphenylmethyl group.

[0095] R 22a When the organic group as the alkyl group is an aralkyl group substituted with a halogen atom, preferred examples thereof include a pentafluorophenylmethyl group, a phenyldifluoromethyl group, a 2-phenyltetrafluoroethyl group, and a 2-(pentafluorophenyl)ethyl group.

[0096] R 22a When the organic group as the alkylthio group is an aralkyl group substituted with an alkylthio group, a suitable example of the organic group as the alkylthio group is a p-methylthiobenzyl group.

[0097] R 22a When the organic group as is an aralkyl group substituted with a halogen atom and an alkylthio group, a suitable example thereof is a 2-(2,3,5,6-tetrafluoro-4-methylthiophenyl)ethyl group.

[0098] R 22aPreferred examples of the organic group as an alkylaryl group include a 2-methylphenyl group, a 3-methylphenyl group, a 4-methylphenyl group, a 3-isopropylphenyl group, a 4-isopropylphenyl group, a 4-n-butylphenyl group, a 4-isobutylphenyl group, a 4-tert-butylphenyl group, a 4-n-hexylphenyl group, a 4-cyclohexylphenyl group, a 4-n-octylphenyl group, a 4-(2-ethyl-n-hexyl)phenyl group, a 2,3-dimethylphenyl group, a 2,4-dimethylphenyl group, a 2,5-dimethylphenyl group, a 2,6-dimethylphenyl group, Examples of such groups include a 3,4-dimethylphenyl group, a 3,5-dimethylphenyl group, a 2,4-di-tert-butylphenyl group, a 2,5-di-tert-butylphenyl group, a 2,6-di-tert-butylphenyl group, a 2,4-di-tert-pentylphenyl group, a 2,5-di-tert-pentylphenyl group, a 2,5-di-tert-octylphenyl group, a 2-cyclohexylphenyl group, a 3-cyclohexylphenyl group, a 4-cyclohexylphenyl group, a 2,4,5-trimethylphenyl group, a 2,4,6-trimethylphenyl group, and a 2,4,6-triisopropylphenyl group.

[0099] The group represented by the formula (a21a) is an ether group-containing group. In formula (a21a), Y 1 Examples of the alkanediyl group having 1 to 4 carbon atoms include a methylene group, an ethane-1,2-diyl group, an ethane-1,1-diyl group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a butane-1,3-diyl group, a butane-2,3-diyl group, and a butane-1,2-diyl group. In formula (a21a), R 27a or R 28aExamples of the alkanediyl group having 2 to 6 carbon atoms include an ethane-1,2-diyl group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, a butane-1,3-diyl group, a butane-2,3-diyl group, a butane-1,2-diyl group, a pentane-1,5-diyl group, a pentane-1,3-diyl group, a pentane-1,4-diyl group, a pentane-2,3-diyl group, a hexane-1,6-diyl group, a hexane-1,2-diyl group, a hexane-1,3-diyl group, a hexane-1,4-diyl group, a hexane-2,5-diyl group, a hexane-2,4-diyl group, and a hexane-3,4-diyl group.

[0100] In formula (a21a), R 27a or R 28a is an alkanediyl group having 2 to 6 carbon atoms substituted with a halogen atom, examples of the halogen atom include a chlorine atom, a bromine atom, an iodine atom, and a fluorine atom. Examples of the alkanediyl group substituted with a halogen atom include a tetrafluoroethane-1,2-diyl group, a 1,1-difluoroethane-1,2-diyl group, a 1-fluoroethane-1,2-diyl group, a 1,2-difluoroethane-1,2-diyl group, a hexafluoropropane-1,3-diyl group, a 1,1,2,2-tetrafluoropropane-1,3-diyl group, and a 1,1,2,2-tetrafluoropentane-1,5-diyl group.

[0101] In formula (a21a), R 27a or R 28aExamples of the aryl group include a 1,2-phenylene group, a 1,3-phenylene group, a 1,4-phenylene group, a 2,5-dimethyl-1,4-phenylene group, a biphenyl-4,4'-diyl group, a diphenylmethane-4,4'-diyl group, a 2,2-diphenylpropane-4,4'-diyl group, a naphthalene-1,2-diyl group, a naphthalene-1,3-diyl group, a naphthalene-1,4-diyl group, a naphthalene-1,5-diyl group, a naphthalene-1,6-diyl group, a naphthalene-1,7-diyl group, a naphthalene-1,8-diyl group, a naphthalene-2,3-diyl group, a naphthalene-2,6-diyl group, and a naphthalene-2,7-diyl group.

[0102] In formula (a21a), R 27a or R 28a is an arylene group substituted with a halogen atom, the halogen atom includes a chlorine atom, a bromine atom, an iodine atom, and a fluorine atom. An example of an arylene group substituted with a halogen atom includes a 2,3,5,6-tetrafluoro-1,4-phenylene group.

[0103] In formula (a21a), R 29a Examples of the alkyl group having 1 to 18 carbon atoms and optionally having a branch, as represented by the formula (I), include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, an isobutyl group, an n-pentyl group, an isopentyl group, a tert-pentyl group, an n-hexyl group, an n-hexane-2-yl group, an n-hexane-3-yl group, an n-heptyl group, an n-heptan-2-yl group, an n-heptan-3-yl group, an isoheptyl group, a tert-heptyl group, an n-octyl group, an isooctyl group, a tert-octyl group, a 2-ethylhexyl group, an n-nonyl group, an isononyl group, an n-decyl group, an n-undecyl group, an n-dodecyl group, an n-tridecyl group, an n-tetradecyl group, an n-pentadecyl group, an n-hexadecyl group, an n-heptadecyl group, and an n-octadecyl group.

[0104] In formula (a21a), R 29ais an alkyl group having 1 to 18 carbon atoms substituted with a halogen atom, examples of the halogen atom include a chlorine atom, a bromine atom, an iodine atom, and a fluorine atom. Examples of the alkyl group substituted with a halogen atom include a trifluoromethyl group, a pentafluoroethyl group, a heptafluoro-n-propyl group, a nonafluoro-n-butyl group, a tridecafluoro-n-hexyl group, a heptadecafluoro-n-octyl group, a 2,2,2-trifluoroethyl group, a 1,1-difluoroethyl group, a 1,1-difluoro-n-propyl group, a 1,1,2,2-tetrafluoro-n-propyl group, a 3,3,3-trifluoro-n-propyl group, a 2,2,3,3,3-pentafluoro-n-propyl group, and a 1,1,2,2-tetrafluorotetradecyl group.

[0105] In formula (a21a), R 29a is an alicyclic hydrocarbon group having 3 to 12 carbon atoms, examples of the alicyclic hydrocarbon constituting the main skeleton of the alicyclic hydrocarbon group include cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, cyclodecane, bicyclo[2.1.1]hexane, bicyclo[2.2.1]heptane, bicyclo[3.2.1]octane, bicyclo[2.2.2]octane, and adamantane. As the alicyclic hydrocarbon group, a group in which one hydrogen atom has been removed from these alicyclic hydrocarbons is preferable.

[0106] In formula (a21a), R 29a is an aryl group, a halogenated aryl group, an aralkyl group, or a halogenated aralkyl group, preferred examples of these groups are R 22a The same applies when these groups are used.

[0107] Among the groups represented by formula (a21a), a suitable group is R 27a In the above-mentioned groups, the carbon atom bonded to the sulfur atom is substituted with a fluorine atom. The number of carbon atoms in such groups is preferably 2 or more and 18 or less.

[0108] R 22aAs R, a perfluoroalkyl group having 1 to 8 carbon atoms is preferable. In addition, a camphor-10-yl group is also preferable because it is easy to form a high-definition resist pattern. 22a As preferred.

[0109] In formula (a21), R 23a ~R 26a is a hydrogen atom or a monovalent organic group. 23a and R 24a And, R 24a and R 25a and, or R 25a and R 26a may be bonded to each other to form a ring. For example, R 25a and R 26a may be bonded to the naphthalene ring to form a five-membered ring, thereby forming an acenaphthene skeleton.

[0110] The monovalent organic group is preferably an alicyclic hydrocarbon group, a heterocyclic group (heterocyclyl group), or an alkyl group or alkoxy group having 4 to 18 carbon atoms which may be substituted with a halogen atom and which may have a branched structure; a heterocyclyloxy group; an alicyclic hydrocarbon group, a heterocyclic group (heterocyclyl group), or an alkylthio group having 4 to 18 carbon atoms which may be substituted with a halogen atom and which may have a branched structure; or a heterocyclylthio group. Also preferred is a group in which a methylene group at any position not adjacent to the oxygen atom of the alkoxy group is substituted with -CO-. Also preferred is an alkoxy group interrupted by an -O-CO- bond or an -O-CO-NH- bond, where the left end of the -O-CO- bond or the -O-CO-NH- bond is closer to the naphthalic acid mother nucleus in the alkoxy group. Furthermore, an alicyclic hydrocarbon group, a heterocyclic group, or an alkylthio group having 4 to 18 carbon atoms which may be substituted with a halogen atom and which may have a branched structure is also included in R. 23a ~R 26a As preferred. Also preferred is an alkylthio group in which a methylene group at any position not adjacent to the sulfur atom is substituted with -CO-. Also preferred is an alkylthio group interrupted by an -O-CO- bond or an -O-CO-NH- bond, where the left end of the -O-CO- bond or the -O-CO-NH- bond is closer to the naphthalic acid mother nucleus in the alkylthio group.

[0111] R 23a ~R 26a As for R 23a is an organic group, and R 24a ~R 26a is a hydrogen atom or R 24a is an organic group, and R 23a , R 25a , and R 26a is preferably a hydrogen atom. 23a ~R 26a may all be hydrogen atoms.

[0112] R 23a ~R 26a Examples of the alkyl group that is an unsubstituted alkyl group include an n-butyl group, a sec-butyl group, a tert-butyl group, an isobutyl group, an n-pentyl group, an isopentyl group, a tert-pentyl group, an n-hexyl group, an n-heptyl group, an isoheptyl group, a tert-heptyl group, an n-octyl group, an isooctyl group, a tert-octyl group, a 2-ethylhexyl group, an n-nonyl group, an n-decyl group, an n-undecyl group, an n-dodecyl group, an n-tridecyl group, an n-tetradecyl group, an n-pentadecyl group, an n-hexadecyl group, an n-heptadecyl group, and an n-octadecyl group.

[0113] R 23a ~R 26aExamples of the alkoxy group represented by the formula (I) include an unsubstituted alkoxy group, such as an n-butyloxy group, a sec-butyloxy group, a tert-butyloxy group, an isobutyloxy group, an n-pentyloxy group, an isopentyloxy group, a tert-pentyloxy group, an n-hexyloxy group, an n-heptyloxy group, an isoheptyloxy group, a tert-heptyloxy group, an n-octyloxy group, an isooctyloxy group, a tert-octyloxy group, a 2-ethylhexyl group, an n-nonyloxy group, an n-decyloxy group, an n-undecyloxy group, an n-dodecyloxy group, an n-tridecyloxy group, an n-tetradecyloxy group, an n-pentadecyloxy group, an n-hexadecyloxy group, an n-heptadecyloxy group, and an n-octadecyloxy group.

[0114] R 23a ~R 26a Examples of the alkylthio group that is an unsubstituted alkylthio group include an n-butylthio group, a sec-butylthio group, a tert-butylthio group, an isobutylthio group, an n-pentylthio group, an isopentylthio group, a tert-pentylthio group, an n-hexylthio group, an n-heptylthio group, an isoheptylthio group, a tert-heptylthio group, an n-octylthio group, an isooctylthio group, a tert-octylthio group, a 2-ethylhexylthio group, an n-nonylthio group, an n-decylthio group, an n-undecylthio group, an n-dodecylthio group, an n-tridecylthio group, an n-tetradecylthio group, an n-pentadecylthio group, an n-hexadecylthio group, an n-heptadecylthio group, and an n-octadecylthio group.

[0115] R 23a ~R 26ais an alkyl group, an alkoxy group, or an alkylthio group substituted with an alicyclic hydrocarbon group, examples of the alicyclic hydrocarbon constituting the main skeleton of the alicyclic hydrocarbon group include cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, cyclodecane, bicyclo[2.1.1]hexane, bicyclo[2.2.1]heptane, bicyclo[3.2.1]octane, bicyclo[2.2.2]octane, and adamantane. As the alicyclic hydrocarbon group, a group in which one hydrogen atom has been removed from these alicyclic hydrocarbons is preferable.

[0116] R 23a ~R 26a is an alkyl group, an alkoxy group, or an alkylthio group substituted with a heterocyclic group, or R 23a ~R 26a When is a heterocyclyloxy group, examples of the heterocycle constituting the heterocyclic group or the main skeleton of the heterocyclyloxy group include pyrrole, thiophene, furan, pyran, thiopyran, imidazole, pyrazole, thiazole, isothiazole, oxazole, isoxazole, pyridine, pyrazine, pyrimidine, pyridazine, pyrrolidine, pyrazolidine, imidazolidine, isoxazolidine, isothiazolidine, piperidine, piperazine, morpholine, thiomorpholine, chroman, thiochroman, isochroman, isothiochroman, indoline, isoindoline, and pyrimidine. Examples of the heterocyclic ring include lindine, indolizine, indole, indazole, purine, quinolizine, isoquinoline, quinoline, naphthyridine, phthalazine, quinoxaline, quinazoline, cinnoline, pteridine, acridine, perimidine, phenanthroline, carbazole, carboline, phenazine, anthridine, thiadiazole, oxadiazole, triazine, triazole, tetrazole, benzimidazole, benzoxazole, benzothiazole, benzothiadiazole, benzofuroxan, naphthoimidazole, benzotriazole, and tetraazaindene. Among these heterocyclic rings, saturated heterocyclic rings in which a ring having a conjugated bond is hydrogenated are also preferred. As the heterocyclic group substituting an alkyl group, an alkoxy group or an alkylthio group, or the heterocyclic group contained in a heterocyclyloxy group, a group in which one hydrogen atom has been removed from the above heterocycle is preferred.

[0117] R 23a ~R 26a is an alkoxy group containing an alicyclic hydrocarbon group, examples of which include a cyclopentyloxy group, a methylcyclopentyloxy group, a cyclohexyloxy group, a fluorocyclohexyloxy group, a chlorocyclohexyloxy group, a cyclohexylmethyloxy group, a methylcyclohexyloxy group, a norbornyloxy group, an ethylcyclohexyloxy group, a cyclohexylethyloxy group, a dimethylcyclohexyloxy group, a methylcyclohexylmethyloxy group, a norbornylmethyloxy group, a trimethylcyclohexyloxy group, Examples of such groups include a cyclohexylbutyloxy group, an adamantyloxy group, a menthyloxy group, an n-butylcyclohexyloxy group, a tert-butylcyclohexyloxy group, a bornyloxy group, an isobornyloxy group, a decahydronaphthyloxy group, a dicyclopentadienoxy group, a 1-cyclohexylpentyloxy group, a methyladamantyloxy group, an adamantylmethyloxy group, a 4-pentylcyclohexyloxy group, a cyclohexylcyclohexyloxy group, an adamantylethyloxy group, and a dimethyladamantyloxy group.

[0118] R 23a ~R 26a When is a heterocyclyloxy group, examples thereof include a tetrahydrofuranyloxy group, a furfuryloxy group, a tetrahydrofurfuryloxy group, a tetrahydropyranyloxy group, a butyrolactonyloxy group, and an indolyloxy group.

[0119] R 23a ~R 26a Examples of the alkylthio group containing an alicyclic hydrocarbon group include a cyclopentylthio group, a cyclohexylthio group, a cyclohexylmethylthio group, a norbornylthio group, and an isonorbornylthio group.

[0120] R 23a ~R 26a When is a heterocyclylthio group, examples thereof include a furfurylthio group and a tetrahydrofuranylthio group.

[0121] R 23a ~R 26a However, examples of the alkoxy group in which a methylene group at any position not adjacent to the oxygen atom of the alkoxy group is substituted with -CO- include a 2-ketobutyl-1-oxy group, a 2-ketopentyl-1-oxy group, a 2-ketohexyl-1-oxy group, a 2-ketoheptyl-1-oxy group, a 2-ketooctyl-1-oxy group, a 3-ketobutyl-1-oxy group, a 4-ketopentyl-1-oxy group, a 5-ketohexyl-1-oxy group, a 6-ketoheptyl-1-oxy group, a 7-ketooctyl-1-oxy group, a 3-methyl-2-ketopentan-4-oxy group, a 2-ketopentan-4-oxy group, a 2-methyl-2-ketopentan-4-oxy group, a 3-ketoheptan-5-oxy group, and a 2-adamantanone-5-oxy group.

[0122] R 23a ~R 26a However, examples of the alkylthio group in which a methylene group at any position not adjacent to the sulfur atom is substituted with -CO- include a 2-ketobutyl-1-thio group, a 2-ketopentyl-1-thio group, a 2-ketohexyl-1-thio group, a 2-ketoheptyl-1-thio group, a 2-ketooctyl-1-thio group, a 3-ketobutyl-1-thio group, a 4-ketopentyl-1-thio group, a 5-ketohexyl-1-thio group, a 6-ketoheptyl-1-thio group, a 7-ketooctyl-1-thio group, a 3-methyl-2-ketopentane-4-thio group, a 2-ketopentane-4-thio group, a 2-methyl-2-ketopentane-4-thio group, and a 3-ketoheptane-5-thio group.

[0123] Specific examples of the compound represented by formula (a21) include the following compounds.

[0124] [ka]

[0125] [ka]

[0126] [ka]

[0127] [ka]

[0128] [ka]

[0129] [ka]

[0130] [ka]

[0131] [ka]

[0132] [ka]

[0133] [ka]

[0134] As the acid generator (A), a naphthalic acid derivative represented by the following formula (a22) is also preferred.

[0135] [ka] In formula (a22), R b1 is a hydrocarbon group having from 1 to 30 carbon atoms. R b1 When the hydrocarbon group as the alkyl group contains one or more methylene groups, at least a part of the methylene groups is -O-, -S-, -CO-, -CO-O-, -SO-, -SO2-, -CR b4 R b5 - and -NR b6 -, and may be substituted with a group selected from the group consisting of: R b1 When the hydrocarbon group as represented by the formula (I) contains a hydrocarbon ring, at least one of the carbon atoms constituting the hydrocarbon ring may be substituted with a heteroatom selected from the group consisting of N, O, P, S, and Se, or an atomic group containing such a heteroatom. R b4 and R b5 are each independently a hydrogen atom or a halogen atom, R b4 and R b5 At least one of the groups is a halogen atom. R b6 is a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms. R a1 , and R a2 each independently represents a hydrogen atom, an aliphatic hydrocarbon group having from 1 to 20 carbon atoms which may have a substituent, an aromatic group having from 5 to 20 ring atoms which may have a substituent, or -R a3 -R a4 It is a group represented by the following formula: R a1 , and R a2 is not a hydrogen atom at the same time. R a1 , or R a2 When the aliphatic hydrocarbon group as represented by formula (I) contains one or more methylene groups, at least a part of the methylene groups is selected from the group consisting of -O-, -S-, -CO-, -CO-O-, -SO-, -SO2-, and -NR a5 -, and may be substituted with a group selected from the group consisting of: R a5 is a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms. R a3is a methylene group, -O-, -CO-, -CO-O-, -SO-, -SO2-, or -NR a6 -It is. R a6 is a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms. R a4 is a heteroarylalkyl group containing an aromatic group having from 5 to 20 ring atoms which may have a substituent, a perfluoroalkyl group having from 1 to 6 carbon atoms which may have a substituent, an aralkyl group having from 7 to 20 carbon atoms which may have a substituent, or an aromatic heterocyclic group having from 5 to 20 ring atoms which may have a substituent. Q 1 , and Q 2 are each independently a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms. L is an ester bond.

[0136] In formula (a22), R a1 and R a2 The aliphatic hydrocarbon group having 1 to 20 carbon atoms as the alkyl group may be linear, branched, or cyclic, or may be a combination of these structures. The aliphatic hydrocarbon group is preferably an alkyl group. Specific preferred examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, a 2-ethylhexyl group, an n-nonyl group, and an n-decyl group. R a1 and R a2 Examples of the substituent that the aliphatic hydrocarbon group having 1 to 20 carbon atoms as R may have include a hydroxyl group, a mercapto group, an amino group, a halogen atom, an oxygen atom, a nitro group, and a cyano group. The number of the substituents is arbitrary. a1 and R a2Examples of the aliphatic hydrocarbon group having 1 to 20 carbon atoms and a substituent as the substituent include perfluoroalkyl groups having 1 to 6 carbon atoms. Specific examples thereof include CF3-, CF3CF2-, (CF3)2CF-, CF3CF2CF2-, CF3CF2CF2CF2-, (CF3)2CFCF2-, CF3CF2(CF3)CF-, and (CF3)3C-.

[0137] In formula (a22), R a1 and R a2 The aromatic group having 5 to 20 ring-constituting atoms which may have a substituent as the aromatic group may be an aromatic hydrocarbon group or an aromatic heterocyclic group. Examples of the aromatic group include aryl groups such as a phenyl group and a naphthyl group, and heteroaryl groups such as a furyl group and a thienyl group. The substituent that the aromatic group having 5 to 20 ring atoms may have is R a1 and R a2 The substituents are the same as those that may be possessed by the aliphatic hydrocarbon group having 1 to 20 carbon atoms as the substituents mentioned above.

[0138] In formula (a22), R a4 The aromatic group having 5 to 20 ring atoms which may have a substituent as R a1 and R a2 The aromatic groups having 5 to 20 ring-constituting atoms which may have a substituent are the same as those described for the aromatic groups having 5 to 20 ring-constituting atoms which may have a substituent. In formula (a22), R a4 The perfluoroalkyl group having 1 to 6 carbon atoms as R a1 and R a2 This is the same as the perfluoroalkyl group having 1 to 6 carbon atoms described above. In formula (a22), R a4 Specific examples of the aralkyl group having 7 to 20 carbon atoms, which may have a substituent as the substituent, include a benzyl group, a phenethyl group, an α-naphthylmethyl group, a β-naphthylmethyl group, a 2-α-naphthylethyl group, and a 2-β-naphthylethyl group. In formula (a22), the heteroarylalkyl group is a group in which some of the carbon atoms constituting the aromatic hydrocarbon ring in the arylalkyl group are substituted with heteroatoms such as N, O, and S. a4 Specific examples of the heteroarylalkyl group containing an aromatic heterocyclic group having 5 to 20 ring-constituting atoms which may have a substituent as the heteroaryl group include a pyridin-2-ylmethyl group, a pyridin-3-ylmethyl group, and a pyridin-4-ylmethyl group.

[0139] In formula (a22), R a5 The hydrocarbon group having 1 to 6 carbon atoms as the alkyl group may be an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a combination thereof. The aliphatic hydrocarbon group may be linear, branched, or cyclic, or may be a combination of these structures. Examples of the aliphatic hydrocarbon group include alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, and n-hexyl. An example of the aromatic hydrocarbon group is a phenyl group.

[0140] In formula (a22), R a6 The hydrocarbon group having 1 to 6 carbon atoms as R a5 This is the same as the hydrocarbon group having 1 to 6 carbon atoms described above.

[0141] In formula (a22), R b1 The hydrocarbon group having 1 to 30 carbon atoms as the alkyl group may be an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a combination thereof. The aliphatic hydrocarbon group may be linear, branched, or cyclic, or may be a combination of these structures. Examples of the aliphatic hydrocarbon group include chain aliphatic hydrocarbon groups such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, and an n-hexyl group, and cyclic aliphatic hydrocarbon groups (hydrocarbon rings) such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, an adamantyl group, and a norbornyl group. Examples of the aromatic hydrocarbon group include a phenyl group and a naphthyl group. Examples of groups in which an aliphatic hydrocarbon group and an aromatic hydrocarbon group are combined include a benzyl group, a phenethyl group, and a furylmethyl group. R b1 When the hydrocarbon group as represented by formula (I) contains a hydrocarbon ring, examples of the atomic group containing a heteroatom substituting at least one of the carbon atoms constituting the hydrocarbon ring include -CO-, -CO-O-, -SO-, -SO2-, -SO2-O-, -P(=O)-(OR b7 )3 can be mentioned. b7 is a hydrocarbon group having 1 to 6 carbon atoms, R a5 This is the same as the hydrocarbon group having 1 to 6 carbon atoms described above.

[0142] In formula (a22), R b4 and R b5 Specific examples of the halogen atom as include a chlorine atom, a fluorine atom, a bromine atom, and an iodine atom.

[0143] In formula (a22), R b6 The hydrocarbon group having 1 to 6 carbon atoms as R in formula (a22) is a5 The above-mentioned hydrocarbon group has 1 to 6 carbon atoms.

[0144] In formula (a22), Q 1 and Q 2 As the perfluoroalkyl group having 1 to 6 carbon atoms, R in formula (a22) a1 and R a2 This is the same as the perfluoroalkyl group having 1 to 6 carbon atoms described above.

[0145] In the compound represented by formula (a22), the direction of the ester bond as L is not particularly limited, and may be either -CO-O- or -O-CO-.

[0146] The compound represented by formula (a22) is preferably a compound represented by the following formula (a22-1): [ka] In formula (a22-1), R b1 , R a1 , Q 1 , and Q 2 are the same as those in formula (a22).

[0147] R in formula (a22-1) a1 is an aliphatic hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, R a1 When the aliphatic hydrocarbon group as represented by formula (I) contains one or more methylene groups, at least a part of the methylene groups is selected from the group consisting of -O-, -S-, -CO-, -CO-O-, -SO-, -SO2-, and -NR a5 A compound represented by formula (a22-1), which may be substituted with a group selected from the group consisting of -, is preferred.

[0148] The compound represented by formula (a22) can be produced by the following method for producing an N-organosulfonyloxy compound. The method for producing an N-organosulfonyloxy compound, which can produce the compound represented by formula (a22), comprises reacting an N-hydroxy compound (a') with a sulfonic acid fluoride compound (b') in the presence of a basic compound (d'), and is characterized in that a silylating agent (c') is present in the system when reacting the N-hydroxy compound (a') with the sulfonic acid fluoride compound (b'), the sulfonic acid fluoride compound (b') being represented by the following formula (b1-1), and the silylating agent (c') being capable of converting the hydroxy group on the nitrogen atom of the N-hydroxy compound (a') to a silyloxy group represented by the following formula (ac1). -O-Si(R c1 )3···(ac1) (In formula (ac1), R c1 are each independently a hydrocarbon group having 1 to 10 carbon atoms. R b1 -L-CQ 1 Q 2 -SO2-F···(b1-1) (In formula (b1-1), R b1 , L, Q 1 , and Q 2 are the same as those in the above formula (a22).

[0149] Furthermore, a method for producing an N-organosulfonyloxy compound, which can produce a compound represented by formula (a22), includes a silylation step of silylating an N-hydroxy compound (a') with a silylating agent (c'), and a condensation step of condensing the silylated product of N-hydroxy compound (a') produced in the silylation step with a sulfonic acid fluoride compound (b') in the presence of a basic compound (d'), wherein the sulfonic acid fluoride compound (b') is represented by the above formula (b1-1), and the silylating agent is capable of converting the hydroxy group on the nitrogen atom of the N-hydroxy compound (a') into a silyloxy group represented by the above formula (ac1).

[0150] The N-hydroxy compound (a') is a compound represented by the following formula (a22-2). [ka] In formula (a22-2), R a1 and R a2 are the same as those in the above formula (a22).

[0151] The N-hydroxy compound (a') can be synthesized by a conventional method, for example, as disclosed in International Publication No. 2014 / 084269 and JP-A-2017-535595. For example, R represented by the formula (a22-1) a2 The compound in which R is a hydrogen atom can be obtained by converting the bromo group on naphthalic anhydride to R by the reaction shown in the following formula, starting from a commercially available bromide. a1 Then, the acid anhydride group is reacted with a hydroxylamine compound such as hydroxylamine hydrochloride to form an N-hydroxyimide. Alternatively, a commercially available product may be used as the N-hydroxy compound (a'). [ka]

[0152] The sulfonic acid fluoride compound (b') can be synthesized by a conventional method. For example, in (b1-1), Q 1 and Q 2 The compound in which is a fluorine atom can be synthesized by the reaction represented by the following formula: Furthermore, a commercially available product may be used as the sulfonic acid fluoride compound (b'). [ka]

[0153] In formula (ac1), R c1The hydrocarbon group having 1 to 10 carbon atoms as the alkyl group may be an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a combination thereof. The aliphatic hydrocarbon group may be linear, branched, or cyclic, or may be a combination of these structures. Examples of the aliphatic hydrocarbon group include alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, 2-ethylhexyl, n-nonyl, and n-decyl. Examples of the aromatic hydrocarbon group include a phenyl group and a naphthyl group.

[0154] The silylating agent (c') includes a compound represented by the following formula (c1). X-Si(R c1 )3···(c1) (In formula (c1), R c1 is R in formula (ac1). c1 where X is a halogen atom.

[0155] In the formula (c1), specific examples of the halogen atom as X include a chlorine atom, a fluorine atom, a bromine atom, and an iodine atom.

[0156] Specific examples of the silylating agent (c') include trimethylsilyl chloride, trimethylsilyl fluoride, trimethylsilyl bromide, t-butyldimethylsilyl chloride, ethyldimethylsilyl chloride, and isopropyldimethylsilyl chloride.

[0157] The basic compound (d') may be an organic base or an inorganic base. Examples of the organic base include nitrogen-containing basic compounds. Specific examples thereof include amines such as methylamine, ethylamine, n-propylamine, isopropylamine, n-butylamine, dimethylamine, diethylamine, di-n-propylamine, diisopropylamine, di-n-butylamine, trimethylamine, triethylamine, methyldiethylamine, N-ethyldiisopropylamine, tri-n-propylamine, triisopropylamine, monoethanolamine, diethanolamine, and triethanolamine; pyrrole, piperidine, 1,8-diaza Examples of the hydroxide ion include cyclic basic compounds such as bicyclo[5,4,0]-7-undecene and 1,5-diazabicyclo[4,3,0]-5-nonane, and quaternary ammonium salts such as tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide, tetrapropylammonium hydroxide (TPAH), tetrabutylammonium hydroxide, methyltripropylammonium hydroxide, methyltributylammonium hydroxide, benzyltrimethylammonium hydroxide, benzyltriethylammonium hydroxide, and trimethyl(2-hydroxyethyl)ammonium hydroxide. Examples of inorganic bases include metal hydroxides, metal hydrogen carbonates, and metal bicarbonates. Specific examples of inorganic bases include metal hydroxides such as lithium hydroxide, potassium hydroxide, sodium hydroxide, rubidium hydroxide, cesium hydroxide, magnesium hydroxide, calcium hydroxide, strontium hydroxide, and barium hydroxide, metal carbonates such as lithium carbonate, potassium carbonate, sodium carbonate, rubidium carbonate, cesium carbonate, magnesium carbonate, calcium carbonate, strontium carbonate, and barium carbonate, and metal bicarbonates such as lithium hydrogen carbonate, potassium hydrogen carbonate, sodium hydrogen carbonate, rubidium hydrogen carbonate, and cesium hydrogen carbonate.

[0158] In the method for producing an N-organosulfonyloxy compound, such an N-hydroxy compound (a') is reacted with a sulfonic acid fluoride compound (b') in the presence of a silylating agent (c') and a basic compound (d'). In this way, when the N-hydroxy compound (a') and the sulfonic acid fluoride compound (b') are reacted in the presence of the basic compound (d'), the silylating agent (c') is present, so that the N-organosulfonyloxy compound can be efficiently produced. For example, the N-organosulfonyloxy compound can be obtained in an amount of 65% or more based on the raw materials N-hydroxy compound (a') and sulfonic acid fluoride compound (b').

[0159] The method for producing an N-organosulfonyloxy compound is a method for producing an N-hydroxy compound (a') by removing a hydrogen atom from a hydroxy group bonded to a nitrogen atom of the N-hydroxy compound (a') and a group derived from a sulfonyl fluoride compound (b'). b1 An N-organosulfonyloxy compound having a structure in which -SO2- is bonded is obtained.

[0160] In the method for producing an N-organosulfonyloxy compound, when an N-hydroxy compound (a') is reacted with a sulfonyl fluoride compound (b') in the presence of a basic compound (d'), it is sufficient that a silylating agent (c') is present in the system. The N-hydroxy compound (a'), the sulfonyl fluoride compound (b'), the silylating agent (c') and the basic compound (d') may be mixed simultaneously, or the sulfonyl fluoride (b') and the basic compound (d') may be added after a partial reaction of the N-hydroxy compound (a') with the silylating agent (c') or after completion of the reaction of the N-hydroxy compound (a') with the silylating agent (c').

[0161] When such an N-hydroxy compound (a') is reacted with a sulfonic acid fluoride compound (b') in the presence of a silylating agent (c') and a basic compound (d'), the N-hydroxy compound (a') is silylated by the silylating agent (c') and the hydroxy group on the nitrogen atom is converted to a silyloxy group represented by the above formula (ac1) (Step 1: silylation step). Then, the silylated product of the N-hydroxy compound (a') produced in the silylation step is condensed with the sulfonic acid fluoride compound (b') treated with the basic compound (d') (Step 2: condensation step), thereby obtaining an N-organosulfonyloxy compound.

[0162] As an example of a method for producing an N-organosulfonyloxy compound, a compound represented by the above formula (a22-2) is used as an N-hydroxy compound (a'), and a compound represented by the above formula (b1-1) Q is used as a sulfonic acid fluoride compound (b'). 1 and Q 2 The reaction formula is shown below when a compound in which is a fluorine atom is used, trimethylsilyl chloride is used as the silylating agent (c'), and triethylamine is used as the basic compound (d'). Note that the reaction mechanism shown below is not one that has been confirmed analytically, but one that is estimated from the raw materials and their behavior during the reaction. [ka] [ka]

[0163] Examples of organic solvents that can be used in the reaction include esters such as ethyl acetate, butyl acetate, and cellosolve acetate, ketones such as acetone, methyl ethyl ketone, isobutyl ketone, and methyl isobutyl ketone, esters such as ethyl acetate, butyl acetate, and diethyl malonate, amides such as N-methylpyrrolidone and N,N-dimethylformamide, ethers such as diethyl ether, ethylcyclopentyl ether, tetrahydrofuran, and dioxane, aromatic hydrocarbons such as toluene and xylene, aliphatic hydrocarbons such as hexane, heptane, octane, and decahydronaphthalene, halogenated hydrocarbons such as chloroform, dichloromethane, methylene chloride, and ethylene chloride, nitrile solvents such as acetonitrile and propionitrile, dimethyl sulfoxide, and dimethyl sulfamide. The organic solvent used may be one type of solvent or two or more types may be used in any combination. The reaction temperature that can be adopted is, for example, in the range of -10°C to 200°C, preferably in the range of 0°C to 150°C, and more preferably in the range of 5°C to 120°C. The reaction time that can be adopted is, for example, from 5 minutes to 20 hours, from 10 minutes to 15 hours, or from 30 minutes to 12 hours.

[0164] It is preferable to use the sulfonic acid fluoride compound (b'), the silylating agent (c') and the basic compound (d') in excess relative to the N-hydroxy compound (a'). For example, it is preferable to use 1.1 to 2.5 moles of the sulfonic acid fluoride compound (b'), 1.1 to 2.5 moles of the silylating agent (c') and 1.1 to 2.5 moles of the basic compound (d') relative to 1.0 mole of the N-hydroxy compound (a').

[0165] The acid generator (A) may be used alone or in combination of two or more. The content of the acid generator (A) is preferably 0.1% by mass or more and 10% by mass or less, more preferably 0.2% by mass or more and 6% by mass or less, and particularly preferably 0.5% by mass or more and 3% by mass or less, based on the total solid content of the photosensitive composition. By setting the amount of the acid generator (A) used within the above range, it is easy to prepare a photosensitive composition that has good sensitivity, is a homogeneous solution, and has excellent storage stability.

[0166] <Resin (B)> The resin (B) whose solubility in alkali increases under the action of an acid is not particularly limited, and any resin whose solubility in alkali increases under the action of an acid can be used. Among them, it is preferable to contain at least one resin selected from the group consisting of novolac resin (B1), polyhydroxystyrene resin (B2), and acrylic resin (B3).

[0167] [Novolac resin (B1)] As the novolak resin (B1), a resin containing a structural unit represented by the following formula (b1) can be used.

[0168] [ka]

[0169] In the above formula (b1), R 1b represents an acid dissociable dissolution inhibiting group, R 2b , R 3b each independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

[0170] Above R 1b The acid dissociable, dissolution inhibiting group represented by the formula (b2) or (b3) below is preferably a linear, branched, or cyclic alkyl group having from 1 to 6 carbon atoms, a vinyloxyethyl group, a tetrahydropyranyl group, a tetrahydrofuranyl group, or a trialkylsilyl group.

[0171] [ka]

[0172] In the above formulas (b2) and (b3), R 4b , R 5b each independently represents a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms; R 6b represents a linear, branched, or cyclic alkyl group having 1 to 10 carbon atoms; R 7b represents a linear, branched, or cyclic alkyl group having from 1 to 6 carbon atoms, and o represents 0 or 1.

[0173] Examples of the linear or branched alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, a neopentyl group, etc. Examples of the cyclic alkyl group include a cyclopentyl group, a cyclohexyl group, etc.

[0174] Here, specific examples of the acid dissociable dissolution inhibiting group represented by the above formula (b2) include a methoxyethyl group, an ethoxyethyl group, an n-propoxyethyl group, an isopropoxyethyl group, an n-butoxyethyl group, an isobutoxyethyl group, a tert-butoxyethyl group, a cyclohexyloxyethyl group, a methoxypropyl group, an ethoxypropyl group, a 1-methoxy-1-methyl-ethyl group, and a 1-ethoxy-1-methylethyl group. Specific examples of the acid dissociable dissolution inhibiting group represented by the above formula (b3) include a tert-butoxycarbonyl group, a tert-butoxycarbonylmethyl group, and the like. Examples of the trialkylsilyl group include a trimethylsilyl group, a tri-tert-butyldimethylsilyl group, and the like, in which the number of carbon atoms in each alkyl group is 1 to 6.

[0175] [Polyhydroxystyrene resin (B2)] As the polyhydroxystyrene resin (B2), a resin containing a structural unit represented by the following formula (b4) can be used.

[0176] [ka]

[0177] In the above formula (b4), R 8b represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms; R 9b represents an acid dissociable, dissolution inhibiting group.

[0178] The alkyl group having from 1 to 6 carbon atoms is, for example, a straight-chain, branched, or cyclic alkyl group having from 1 to 6 carbon atoms. Examples of the straight-chain or branched alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group, and examples of the cyclic alkyl group include a cyclopentyl group, and a cyclohexyl group.

[0179] Above R 9bAs the acid dissociable, dissolution inhibiting group represented by the formula (b2) or (b3) above, the same acid dissociable, dissolution inhibiting groups as those exemplified above can be used.

[0180] Furthermore, the polyhydroxystyrene resin (B2) may contain other polymerizable compounds as constituent units for the purpose of appropriately controlling the physical and chemical properties. Examples of such polymerizable compounds include known radically polymerizable compounds and anionically polymerizable compounds. Examples of such polymerizable compounds include monocarboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid; dicarboxylic acids such as maleic acid, fumaric acid, and itaconic acid; methacrylic acid derivatives having a carboxy group and an ester bond such as 2-methacryloyloxyethyl succinic acid, 2-methacryloyloxyethyl maleic acid, 2-methacryloyloxyethyl phthalic acid, and 2-methacryloyloxyethyl hexahydrophthalic acid; (meth)acrylic acid alkyl esters such as methyl (meth)acrylate, ethyl (meth)acrylate, and butyl (meth)acrylate; (meth)acrylic acid hydroxyalkyl esters such as 2-hydroxyethyl (meth)acrylate and 2-hydroxypropyl (meth)acrylate; phenyl (meth)acrylate, phenyl (meth)acrylate, and phenyl (meth)acrylate. Examples of suitable polymerizable compounds include (meth)acrylic acid aryl esters such as diethyl maleate and dibutyl fumarate; dicarboxylic acid diesters such as diethyl maleate and dibutyl fumarate; vinyl group-containing aromatic compounds such as styrene, α-methylstyrene, chlorostyrene, chloromethylstyrene, vinyltoluene, hydroxystyrene, α-methylhydroxystyrene and α-ethylhydroxystyrene; vinyl group-containing aliphatic compounds such as vinyl acetate; conjugated diolefins such as butadiene and isoprene; nitrile group-containing polymerizable compounds such as acrylonitrile and methacrylonitrile; chlorine-containing polymerizable compounds such as vinyl chloride and vinylidene chloride; and amide bond-containing polymerizable compounds such as acrylamide and methacrylamide.

[0181] [Acrylic resin (B3)] The acrylic resin (B3) is not particularly limited as long as it is an acrylic resin whose solubility in alkali increases under the action of an acid and which has been conventionally blended in various photosensitive compositions. The acrylic resin (B3) preferably contains a structural unit (b-3) derived from an acrylic acid ester containing, for example, an -SO- containing cyclic group or a lactone-containing cyclic group. In such a case, when forming a resist pattern, it is easy to form a resist pattern having a preferable cross-sectional shape.

[0182] (-SO2-containing cyclic group) Here, the term "-SO2-containing cyclic group" refers to a cyclic group containing a ring containing -SO2- in its ring structure, specifically, a cyclic group in which the sulfur atom (S) in -SO2- forms a part of the ring structure of the cyclic group. The ring containing -SO2- in the ring structure is counted as the first ring, and if there is only this ring, it is called a monocyclic group, and if there is another ring structure, it is called a polycyclic group regardless of the structure. The -SO2-containing cyclic group may be monocyclic or polycyclic.

[0183] The -SO2- containing cyclic group is preferably a cyclic group containing -O-SO2- in its ring skeleton, that is, a cyclic group containing a sultone ring in which -OS- in -O-SO2- forms a part of the ring skeleton.

[0184] The number of carbon atoms in the -SO2- containing cyclic group is preferably from 3 to 30, more preferably from 4 to 20, further preferably from 4 to 15, and particularly preferably from 4 to 12. The number of carbon atoms is the number of carbon atoms constituting the ring skeleton and does not include the number of carbon atoms in the substituent.

[0185] The -SO2- containing cyclic group may be an -SO2- containing aliphatic cyclic group or an -SO2- containing aromatic cyclic group, preferably an -SO2- containing aliphatic cyclic group.

[0186] Examples of the -SO2- containing aliphatic cyclic group include a group in which at least one hydrogen atom has been removed from an aliphatic hydrocarbon ring in which a portion of the carbon atoms constituting the ring skeleton is substituted with -SO2- or -O-SO2-. More specifically, examples thereof include a group in which at least one hydrogen atom has been removed from an aliphatic hydrocarbon ring in which -CH2- constituting the ring skeleton is substituted with -SO2-, a group in which at least one hydrogen atom has been removed from an aliphatic hydrocarbon ring in which -CH2-CH2- constituting the ring skeleton is substituted with -O-SO2-, and the like.

[0187] The number of carbon atoms in the alicyclic hydrocarbon ring is preferably 3 to 20, more preferably 3 to 12. The alicyclic hydrocarbon ring may be polycyclic or monocyclic. The monocyclic alicyclic hydrocarbon group is preferably a group in which two hydrogen atoms have been removed from a monocycloalkane having 3 to 6 carbon atoms. Examples of the monocycloalkane include cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon ring is preferably a group in which two hydrogen atoms have been removed from a polycycloalkane having 7 to 12 carbon atoms, and specific examples of the polycycloalkane include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

[0188] The -SO2- containing cyclic group may have a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, an oxygen atom (=O), -COOR", -OC(=O)R", a hydroxyalkyl group, and a cyano group.

[0189] The alkyl group as the substituent is preferably an alkyl group having 1 to 6 carbon atoms. The alkyl group is preferably linear or branched. Specific examples include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, neopentyl, and n-hexyl groups. Among these, methyl and ethyl groups are preferred, and methyl groups are particularly preferred.

[0190] The alkoxy group as the substituent is preferably an alkoxy group having 1 to 6 carbon atoms. The alkoxy group is preferably linear or branched. Specific examples include groups in which the alkyl groups listed above as the alkyl groups as the substituent are bonded to an oxygen atom (-O-).

[0191] Examples of the halogen atom as the substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, with a fluorine atom being preferred.

[0192] Examples of the halogenated alkyl group for the substituent include the above-mentioned alkyl groups in which some or all of the hydrogen atoms have been substituted with the above-mentioned halogen atoms.

[0193] Examples of the halogenated alkyl group as the substituent include the alkyl groups listed above as the alkyl groups as the substituent, in which some or all of the hydrogen atoms are substituted with the halogen atoms listed above. As the halogenated alkyl group, a fluorinated alkyl group is preferred, and a perfluoroalkyl group is particularly preferred.

[0194] R″ in the above-mentioned —COOR″ and —OC(═O)R″ is either a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 15 carbon atoms.

[0195] When R″ is a linear or branched alkyl group, the linear alkyl group preferably has 1 or more and 10 or less, more preferably 1 or more and 5 or less, and particularly preferably 1 or 2 carbon atoms.

[0196] When R" is a cyclic alkyl group, the cyclic alkyl group preferably has 3 or more and 15 or less carbon atoms, more preferably 4 or more and 12 or less, and particularly preferably 5 or more and 10 or less. Specific examples include monocycloalkanes which may or may not be substituted with a fluorine atom or a fluorinated alkyl group, and groups in which one or more hydrogen atoms have been removed from polycycloalkanes such as bicycloalkanes, tricycloalkanes, and tetracycloalkanes. More specific examples include groups in which one or more hydrogen atoms have been removed from monocycloalkanes such as cyclopentane and cyclohexane, and polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

[0197] The hydroxyalkyl group as the substituent is preferably a hydroxyalkyl group having from 1 to 6 carbon atoms. Specific examples thereof include groups in which at least one hydrogen atom of the alkyl groups listed above as the alkyl group as the substituent is substituted with a hydroxyl group.

[0198] More specific examples of the -SO2- containing cyclic group include groups represented by the following formulas (3-1) to (3-4). [ka] (In the formula, A' is an alkylene group having 1 to 5 carbon atoms which may contain an oxygen atom or a sulfur atom, an oxygen atom, or a sulfur atom; z is an integer of 0 to 2; R 10b is an alkyl group, an alkoxy group, a halogenated alkyl group, a hydroxyl group, -COOR", -OC(=O)R", a hydroxyalkyl group, or a cyano group, and R" is a hydrogen atom or an alkyl group.

[0199] In the above formulas (3-1) to (3-4), A' is an alkylene group having 1 to 5 carbon atoms which may contain an oxygen atom (-O-) or a sulfur atom (-S-), an oxygen atom, or a sulfur atom. The alkylene group having 1 to 5 carbon atoms in A' is preferably a linear or branched alkylene group, and examples of such groups include a methylene group, an ethylene group, an n-propylene group, and an isopropylene group.

[0200] When the alkylene group contains an oxygen atom or a sulfur atom, specific examples thereof include groups in which -O- or -S- is present at the terminal or between carbon atoms of the alkylene group, such as -O-CH2-, -CH2-O-CH2-, -S-CH2-, -CH2-S-CH2-, etc. A' is preferably an alkylene group having 1 to 5 carbon atoms or -O-, more preferably an alkylene group having 1 to 5 carbon atoms, and most preferably a methylene group.

[0201] z may be any of 0, 1, and 2, and is most preferably 0. When z is 2, a plurality of R 10b may be the same or different.

[0202] R 10b Examples of the alkyl group, alkoxy group, halogenated alkyl group, -COOR", -OC(=O)R", and hydroxyalkyl group in the above formula include the same as those described above for the alkyl group, alkoxy group, halogenated alkyl group, -COOR", -OC(=O)R", and hydroxyalkyl group listed as the substituent that the -SO- containing cyclic group may have.

[0203] Specific examples of the cyclic groups represented by the above formulas (3-1) to (3-4) are shown below, in which "Ac" represents an acetyl group.

[0204] [ka]

[0205] [ka]

[0206] As the -SO2- containing cyclic group, among the above, the group represented by the above formula (3-1) is preferable, at least one selected from the group consisting of the groups represented by any one of the above chemical formulas (3-1-1), (3-1-18), (3-3-1), and (3-4-1) is more preferable, and the group represented by the above chemical formula (3-1-1) is most preferable.

[0207] (Lactone-containing cyclic group) A "lactone-containing cyclic group" refers to a cyclic group that contains a ring (lactone ring) containing -OC(=O)- in its ring skeleton. The lactone ring is counted as the first ring, and when there is only a lactone ring, it is called a monocyclic group, and when there is further a ring structure, it is called a polycyclic group regardless of the structure. The lactone-containing cyclic group may be a monocyclic group or a polycyclic group.

[0208] The lactone cyclic group in the structural unit (b-3) is not particularly limited and any one can be used.Specifically, lactone-containing monocyclic groups include groups in which one hydrogen atom is removed from 4- to 6-membered ring lactones, such as groups in which one hydrogen atom is removed from β-propionolactone, groups in which one hydrogen atom is removed from γ-butyrolactone, and groups in which one hydrogen atom is removed from δ-valerolactone.Furthermore, lactone-containing polycyclic groups include groups in which one hydrogen atom is removed from bicycloalkanes, tricycloalkanes, and tetracycloalkanes having a lactone ring.

[0209] As the structural unit (b-3), there are no particular limitations on the structure of the other portions as long as it has an -SO2- containing cyclic group or a lactone-containing cyclic group, but at least one structural unit selected from the group consisting of structural units (b-3-S) derived from an acrylate ester in which the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent and which contain an -SO2- containing cyclic group, and structural units (b-3-L) derived from an acrylate ester in which the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent and which contain a lactone-containing cyclic group are preferred.

[0210] [Structural unit (b-3-S)] More specific examples of the structural unit (b-3-S) include structural units represented by the following formula (b-S1).

[0211] [ka] (In the formula, R is a hydrogen atom, an alkyl group having from 1 to 5 carbon atoms, or a halogenated alkyl group having from 1 to 5 carbon atoms; R 11b is a -SO2- containing cyclic group, R 12b is a single bond or a divalent linking group.

[0212] In formula (b-S1), R is the same as defined above. R 11b is the same as the -SO2- containing cyclic group mentioned above. R 12b may be either a single bond or a divalent linking group.

[0213] R 12b The divalent linking group in is not particularly limited, but suitable examples include a divalent hydrocarbon group which may have a substituent, and a divalent linking group containing a hetero atom.

[0214] Optionally substituted divalent hydrocarbon group The hydrocarbon group as the divalent linking group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. The aliphatic hydrocarbon group means a hydrocarbon group that does not have aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated. Generally, a saturated hydrocarbon group is preferred. More specifically, the aliphatic hydrocarbon group may be a straight-chain or branched-chain aliphatic hydrocarbon group, an aliphatic hydrocarbon group containing a ring in its structure, and the like.

[0215] The linear or branched aliphatic hydrocarbon group preferably has 1 or more and 10 or less, more preferably 1 or more and 8 or less, and even more preferably 1 or more and 5 or less, carbon atoms.

[0216] As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, specifically, a methylene group [-CH2-], an ethylene group [-(CH2)2-], a trimethylene group [-(CH2)3-], a tetramethylene group [-(CH2)4-], a pentamethylene group [-(CH2)5-], etc. can be mentioned.

[0217] The branched aliphatic hydrocarbon group is preferably a branched alkylene group. Specific examples thereof include alkyl methylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, and -C(CH2CH3)2-; alkyl ethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, and -C(CH2CH3)2-CH2-; alkyl trimethylene groups such as -CH(CH3)CH2CH2-, and -CH2CH(CH3)CH2-; and alkyl tetramethylene groups such as -CH(CH3)CH2CH2CH2-, and -CH2CH(CH3)CH2CH2-. The alkyl group in the alkylalkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

[0218] The linear or branched aliphatic hydrocarbon group may or may not have a substituent (a group or atom other than a hydrogen atom) that replaces a hydrogen atom. Examples of the substituent include a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms and substituted with a fluorine atom, and an oxo group (=O).

[0219] Examples of the aliphatic hydrocarbon group containing a ring in the above structure include a cyclic aliphatic hydrocarbon group (a group in which two hydrogen atoms have been removed from an aliphatic hydrocarbon ring) which may contain a substituent containing a heteroatom in the ring structure, a group in which the cyclic aliphatic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, and a group in which the cyclic aliphatic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group, etc. Examples of the linear or branched aliphatic hydrocarbon group include the same as those described above.

[0220] The cyclic aliphatic hydrocarbon group preferably has 3 or more and 20 or less, and more preferably has 3 or more and 12 or less, carbon atoms.

[0221] The cyclic aliphatic hydrocarbon group may be polycyclic or monocyclic. The monocyclic aliphatic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a monocycloalkane. The number of carbon atoms in the monocycloalkane is preferably 3 or more and 6 or less. Specific examples include cyclopentane and cyclohexane. The polycyclic aliphatic hydrocarbon group is preferably a group obtained by removing two hydrogen atoms from a polycycloalkane. The number of carbon atoms in the polycycloalkane is preferably 7 or more and 12 or less. Specific examples include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

[0222] The cyclic aliphatic hydrocarbon group may or may not have a substituent (a group or atom other than a hydrogen atom) that replaces a hydrogen atom. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, and an oxo group (=O).

[0223] The alkyl group as the above-mentioned substituent is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.

[0224] The alkoxy group as the above-mentioned substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert-butoxy group, and particularly preferably a methoxy group or an ethoxy group.

[0225] Examples of the halogen atom as the above-mentioned substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, with a fluorine atom being preferred.

[0226] Examples of the halogenated alkyl group as the above-mentioned substituent include the above-mentioned alkyl groups in which some or all of the hydrogen atoms have been substituted with the above-mentioned halogen atoms.

[0227] In the cyclic aliphatic hydrocarbon group, a part of the carbon atoms constituting the ring structure may be substituted with -O- or -S-. As the substituent containing a hetero atom, -O-, -C(=O)-O-, -S-, -S(=O)2-, and -S(=O)2-O- are preferred.

[0228] The aromatic hydrocarbon group as a divalent hydrocarbon group is a divalent hydrocarbon group having at least one aromatic ring, and may have a substituent. The aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic or polycyclic. The number of carbon atoms in the aromatic ring is preferably 5 to 30, more preferably 5 to 20, even more preferably 6 to 15, and particularly preferably 6 to 12. However, the number of carbon atoms does not include the number of carbon atoms of the substituent.

[0229] Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; aromatic heterocycles in which a part of the carbon atoms constituting the aromatic hydrocarbon ring is replaced with a heteroatom; and the like. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring.

[0230] Specific examples of the aromatic hydrocarbon group as a divalent hydrocarbon group include a group in which two hydrogen atoms have been removed from the above-mentioned aromatic hydrocarbon ring or aromatic heterocycle (arylene group, or heteroarylene group); a group in which two hydrogen atoms have been removed from an aromatic compound containing two or more aromatic rings (e.g., biphenyl, fluorene, etc.); a group in which one hydrogen atom of a group in which one hydrogen atom has been removed from the above-mentioned aromatic hydrocarbon ring or aromatic heterocycle (aryl group, or heteroaryl group) has been substituted with an alkylene group (e.g., a group in which one further hydrogen atom has been removed from the aryl group in an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, or a 2-naphthylethyl group); and the like.

[0231] The alkylene group bonded to the aryl group or heteroaryl group preferably has 1 or more and 4 or less, more preferably 1 or more and 2 or less, and particularly preferably 1.

[0232] The aromatic hydrocarbon group may have a hydrogen atom substituted with a substituent. For example, a hydrogen atom bonded to an aromatic ring in the aromatic hydrocarbon group may be substituted with a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, and an oxo group (=O).

[0233] The alkyl group as the above-mentioned substituent is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group, an ethyl group, an n-propyl group, an n-butyl group, or a tert-butyl group.

[0234] The alkoxy group as the above-mentioned substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert-butoxy group, and more preferably a methoxy group or an ethoxy group.

[0235] Examples of the halogen atom as the above-mentioned substituent include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc., with a fluorine atom being preferred.

[0236] Examples of the halogenated alkyl group as the above-mentioned substituent include the above-mentioned alkyl groups in which some or all of the hydrogen atoms have been substituted with the above-mentioned halogen atoms.

[0237] Divalent linking group containing a heteroatom The heteroatom in the divalent linking group containing a heteroatom is an atom other than a carbon atom or a hydrogen atom, and examples thereof include an oxygen atom, a nitrogen atom, a sulfur atom, and a halogen atom.

[0238] Specific examples of the divalent linking group containing a heteroatom include non-hydrocarbon linking groups such as -O-, -C(=O)-, -C(=O)-O-, -OC(=O)-O-, -S-, -S(=O)2-, -S(=O)2-O-, -NH-, -NH-C(=O)-, -NH-C(=NH)-, =N-, and the like, as well as combinations of at least one of these non-hydrocarbon linking groups with a divalent hydrocarbon group. Examples of the divalent hydrocarbon group include the same as the divalent hydrocarbon group that may have the above-mentioned substituent, and linear or branched aliphatic hydrocarbon groups are preferred.

[0239] Among the above, -NH- in -C(=O)-NH-, -NH-, and H in -NH-C(=NH)- may each be substituted with a substituent such as an alkyl group, an acyl group, etc. The number of carbon atoms in the substituent is preferably 1 to 10, more preferably 1 to 8, and particularly preferably 1 to 5.

[0240] R 12bAs the divalent linking group in the above formula, a linear or branched alkylene group, a cyclic aliphatic hydrocarbon group, or a divalent linking group containing a hetero atom is particularly preferred.

[0241] R 12b When the divalent linking group in is a linear or branched alkylene group, the number of carbon atoms in the alkylene group is preferably from 1 to 10, more preferably from 1 to 6, particularly preferably from 1 to 4, and most preferably from 1 to 3. Specific examples thereof include the same linear alkylene groups and branched alkylene groups as those exemplified as the linear or branched aliphatic hydrocarbon groups in the explanation of the "divalent hydrocarbon group which may have a substituent" described above as the divalent linking group.

[0242] R 12b When the divalent linking group in is a cyclic aliphatic hydrocarbon group, examples of the cyclic aliphatic hydrocarbon group include the same as the cyclic aliphatic hydrocarbon groups exemplified as the "aliphatic hydrocarbon group having a ring in its structure" in the explanation of the "divalent hydrocarbon group which may have a substituent" as the above-mentioned divalent linking group.

[0243] As the cyclic aliphatic hydrocarbon group, a group in which two or more hydrogen atoms have been removed from cyclopentane, cyclohexane, norbornane, isobornane, adamantane, tricyclodecane, or tetracyclododecane is particularly preferred.

[0244] R 12b When the divalent linking group in the formula (I) is a divalent linking group containing a hetero atom, preferred examples of the linking group include -O-, -C(=O)-O-, -C(=O)-, -OC(=O)-O-, -C(=O)-NH-, -NH- (H may be substituted with a substituent such as an alkyl group or an acyl group), -S-, -S(=O)2-, -S(=O)2-O-, and a group represented by the general formula -Y 1 -OY 2 -, -[Y 1 -C(=O)-O] m’ -Y 2 - or -Y 1 A group represented by —OC(═O)—Y—,1 , and Y 2 each independently represents a divalent hydrocarbon group which may have a substituent, O is an oxygen atom, and m' is an integer of 0 or more and 3 or less.

[0245] R 12b When the divalent linking group in is -NH-, the hydrogen atom in -NH- may be substituted with a substituent such as an alkyl group, acyl, etc. The number of carbon atoms in the substituent (alkyl group, acyl group, etc.) is preferably 1 to 10, more preferably 1 to 8, and particularly preferably 1 to 5.

[0246] Formula-Y 1 -OY 2 -, -[Y 1 -C(=O)-O] m’ -Y 2 - or -Y 1 -OC(=O)-Y 2 -Medium, Y 1 , and Y 2 are each independently a divalent hydrocarbon group which may have a substituent. Examples of the divalent hydrocarbon group include the same ones as the "divalent hydrocarbon group which may have a substituent" listed above in the description of the divalent linking group.

[0247] Y 1 As the alkyl group, a linear aliphatic hydrocarbon group is preferable, a linear alkylene group is more preferable, a linear alkylene group having 1 to 5 carbon atoms is even more preferable, and a methylene group and an ethylene group are particularly preferable.

[0248] Y 2 is preferably a linear or branched aliphatic hydrocarbon group, more preferably a methylene group, an ethylene group, or an alkylmethylene group. The alkyl group in the alkylmethylene group is preferably a linear alkyl group having 1 to 5 carbon atoms, more preferably a linear alkyl group having 1 to 3 carbon atoms, and particularly preferably a methyl group.

[0249] Formula − [Y 1 -C(=O)-O]m’ -Y 2 In the group represented by -, m' is an integer of 0 to 3, preferably an integer of 0 to 2, more preferably 0 or 1, and particularly preferably 1. That is, the group represented by the formula -[Y 1 -C(=O)-O] m’ -Y 2 The group represented by the formula -Y 1 -C(=O)-OY 2 Particularly preferred is a group represented by the formula -(CH2) a’ -C(=O)-O-(CH2) b’ In the formula, a' is an integer of 1 or more and 10 or less, preferably an integer of 1 or more and 8 or less, more preferably an integer of 1 or more and 5 or less, even more preferably 1 or 2, and most preferably 1. b' is an integer of 1 or more and 10 or less, preferably an integer of 1 or more and 8 or less, more preferably an integer of 1 or more and 5 or less, even more preferably 1 or 2, and most preferably 1.

[0250] R 12b As for the divalent linking group in the formula (I), the divalent linking group containing a hetero atom is preferably an organic group consisting of a combination of at least one non-hydrocarbon group and a divalent hydrocarbon group. Among them, a linear group having an oxygen atom as a hetero atom, for example, a group containing an ether bond or an ester bond, is preferred, and the above-mentioned formula -Y 1 -OY 2 -, -[Y 1 -C(=O)-O] m’ -Y 2 - or -Y 1 -OC(=O)-Y 2 A group represented by the above formula -[Y 1 -C(=O)-O] m’ -Y 2 - or -Y 1 -OC(=O)-Y 2 A group represented by - is particularly preferred.

[0251] R 12b The divalent linking group in is preferably an alkylene group or one containing an ester bond (-C(=O)-O-).

[0252] The alkylene group is preferably a linear or branched alkylene group. Suitable examples of the linear aliphatic hydrocarbon group include a methylene group [-CH2-], an ethylene group [-(CH2)2-], a trimethylene group [-(CH2)3-], a tetramethylene group [-(CH2)4-], and a pentamethylene group [-(CH2)5-]. Suitable examples of the branched alkylene group include alkyl methylene groups such as -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)2-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, -C(CH2CH3)2-, etc.; alkyl ethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, -C(CH2CH3)2-CH2-, etc.; alkyl trimethylene groups such as -CH(CH3)CH2CH2- and -CH2CH(CH3)CH2-; and alkyl tetramethylene groups such as -CH(CH3)CH2CH2CH2- and -CH2CH(CH3)CH2CH2-.

[0253] As the divalent linking group containing an ester bond, particularly, a group represented by the formula: -R 13b -C(=O)-O-[wherein, R 13b is a divalent linking group. In other words, the structural unit (b-3-S) is preferably a structural unit represented by the following formula (b-S1-1).

[0254] [ka] (Wherein, R and R 11b are the same as above, and R 13b is a divalent linking group.

[0255] R 13b is not particularly limited, and examples thereof include the above-mentioned R 12b The divalent linking group may be the same as the divalent linking group in the above formula. R 13bThe divalent linking group is preferably a linear or branched alkylene group, an aliphatic hydrocarbon group containing a ring in the structure, or a divalent linking group containing a heteroatom, and is preferably a linear or branched alkylene group or a divalent linking group containing an oxygen atom as a heteroatom.

[0256] As the linear alkylene group, a methylene group or an ethylene group is preferable, and a methylene group is particularly preferable. As the branched alkylene group, an alkylmethylene group or an alkylethylene group is preferable, and -CH(CH3)-, -C(CH3)2-, or -C(CH3)2CH2- is particularly preferable.

[0257] The divalent linking group containing an oxygen atom is preferably a divalent linking group containing an ether bond or an ester bond, and the above-mentioned -Y 1 -OY 2 -, -[Y 1 -C(=O)-O] m’ -Y 2 - or -Y 1 -OC(=O)-Y 2 - is more preferable. 1 , and Y 2 are each independently a divalent hydrocarbon group which may have a substituent, and m' is an integer of 0 to 3. 1 -OC(=O)-Y 2 - is preferred, -(CH2) c -OC(=O)-(CH2) d A group represented by the formula - is particularly preferred. c is an integer of 1 or more and 5 or less, and preferably 1 or 2. d is an integer of 1 or more and 5 or less, and preferably 1 or 2.

[0258] As the structural unit (b-3-S), a structural unit represented by the following formula (b-S1-11) or (b-S1-12) is particularly preferable, and a structural unit represented by formula (b-S1-12) is more preferable.

[0259] [ka] (In the formula, R, A', R 10b, z, and R 13b are the same as above.)

[0260] In formula (b-S1-11), A' is preferably a methylene group, an oxygen atom (-O-), or a sulfur atom (-S-).

[0261] R 13b R is preferably a linear or branched alkylene group or a divalent linking group containing an oxygen atom. 13b Examples of the linear or branched alkylene group and the divalent linking group containing an oxygen atom in the above formula (I) include the same as the linear or branched alkylene group and the divalent linking group containing an oxygen atom described above, respectively.

[0262] As the constitutional unit represented by formula (b-S1-12), a constitutional unit represented by the following formula (b-S1-12a) or (b-S1-12b) is particularly preferable.

[0263] [ka] (In the formula, R and A' are the same as defined above, and c to e each independently represent an integer of 1 or more and 3 or less.)

[0264] [Structural unit (b-3-L)] Examples of the structural unit (b-3-L) include R 11b with a lactone-containing cyclic group, and more specific examples include structural units represented by the following formulas (b-L1) to (b-L5).

[0265] [ka] (In the formula, R is a hydrogen atom, an alkyl group having from 1 to 5 carbon atoms, or a halogenated alkyl group having from 1 to 5 carbon atoms; R' is independently a hydrogen atom, an alkyl group, an alkoxy group, a halogenated alkyl group, a hydroxyl group, -COOR", -OC(=O)R", a hydroxyalkyl group, or a cyano group, and R" is a hydrogen atom or an alkyl group; R 12b is a single bond or a divalent linking group, s″ is an integer of 0 to 2; A″ is an alkylene group having 1 to 5 carbon atoms which may contain an oxygen atom or a sulfur atom, an oxygen atom, or a sulfur atom; and r is 0 or 1.

[0266] R in the formulae (b-L1) to (b-L5) is the same as defined above. Examples of the alkyl group, alkoxy group, halogenated alkyl group, -COOR", -OC(=O)R", and hydroxyalkyl group for R' include the same as those described above for the alkyl group, alkoxy group, halogenated alkyl group, -COOR", -OC(=O)R", and hydroxyalkyl group listed as the substituent that the -SO- containing cyclic group may have, respectively.

[0267] Considering industrial availability and the like, R' is preferably a hydrogen atom. The alkyl group in R'' may be linear, branched, or cyclic. When R″ is a linear or branched alkyl group, it preferably has 1 to 10 carbon atoms, and more preferably has 1 to 5 carbon atoms. When R" is a cyclic alkyl group, it preferably has 3 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specific examples include groups in which one or more hydrogen atoms have been removed from polycycloalkanes such as monocycloalkanes, bicycloalkanes, tricycloalkanes, and tetracycloalkanes, which may or may not be substituted with a fluorine atom or a fluorinated alkyl group. Specific examples include groups in which one or more hydrogen atoms have been removed from monocycloalkanes such as cyclopentane and cyclohexane, and polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Examples of A" include the same as A' in the above formula (3-1). A" is preferably an alkylene group having 1 to 5 carbon atoms, an oxygen atom (-O-) or a sulfur atom (-S-), more preferably an alkylene group having 1 to 5 carbon atoms or -O-. As the alkylene group having 1 to 5 carbon atoms, a methylene group or a dimethylmethylene group is more preferable, and a methylene group is most preferable.

[0268] R 12b is R in the above formula (b-S1). 12b is the same as: In formula (b-L1), s″ is preferably 1 or 2. Specific examples of the structural units represented by the above formulas (b-L1) to (b-L3) are shown below. In each of the following formulas, R α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.

[0269] [ka]

[0270] [ka]

[0271] [ka]

[0272] The structural unit (b-3-L) is preferably at least one selected from the group consisting of structural units represented by the above formulas (b-L1) to (b-L5), more preferably at least one selected from the group consisting of structural units represented by the above formulas (b-L1) to (b-L3), and particularly preferably at least one selected from the group consisting of structural units represented by the above formula (b-L1) or (b-L3). Among these, at least one selected from the group consisting of structural units represented by the aforementioned formulas (b-L1-1), (b-L1-2), (b-L2-1), (b-L2-7), (b-L2-12), (b-L2-14), (b-L3-1), and (b-L3-5) is preferred.

[0273] Furthermore, as the structural unit (b-3-L), structural units represented by the following formulas (b-L6) to (b-L7) are also preferred. [ka] In formulas (b-L6) and (b-L7), R and R 12b is the same as above.

[0274] The acrylic resin (B3) also contains structural units represented by the following formulas (b5) to (b7) having an acid-dissociable group as structural units that increase the solubility of the acrylic resin (B3) in alkali by the action of an acid.

[0275] [ka]

[0276] In the above formulas (b5) to (b7), R 14b , and R 18b ~R 23b each independently represents a hydrogen atom, a linear or branched alkyl group having from 1 to 6 carbon atoms, a fluorine atom, or a linear or branched fluorinated alkyl group having from 1 to 6 carbon atoms; R 15b ~R17b each independently represents a linear or branched alkyl group having 1 to 6 carbon atoms, a linear or branched fluorinated alkyl group having 1 to 6 carbon atoms, or an aliphatic cyclic group having 5 to 20 carbon atoms, each independently represents a linear or branched alkyl group having 1 to 6 carbon atoms, or a linear or branched fluorinated alkyl group having 1 to 6 carbon atoms, R 16b and R 17b may be bonded to each other to form a hydrocarbon ring having 5 to 20 carbon atoms together with the carbon atom to which they are bonded; Y b represents an aliphatic cyclic group or an alkyl group which may have a substituent; p represents an integer of 0 or more and 4 or less; and q represents 0 or 1.

[0277] Examples of the linear or branched alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, a neopentyl group, etc. A fluorinated alkyl group is an alkyl group in which some or all of the hydrogen atoms are substituted with fluorine atoms. Specific examples of the aliphatic cyclic group include groups in which one or more hydrogen atoms have been removed from polycycloalkanes such as monocycloalkanes, bicycloalkanes, tricycloalkanes, and tetracycloalkanes. Specific examples include groups in which one hydrogen atom has been removed from monocycloalkanes such as cyclopentane, cyclohexane, cycloheptane, and cyclooctane, and polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. In particular, groups in which one hydrogen atom has been removed from cyclohexane and adamantane (which may further have a substituent) are preferred.

[0278] Above R 16b and R 17b When R 15b , R 16b , and R 17bFrom the viewpoints of high contrast, resolution, focal depth range, etc., R is preferably a linear or branched alkyl group having 1 to 4 carbon atoms, and more preferably a linear or branched alkyl group having 2 to 4 carbon atoms. 19b , R 20b , R 22b , R 23b is preferably a hydrogen atom or a methyl group.

[0279] Above R 16b and R 17b may form an aliphatic cyclic group having 5 to 20 carbon atoms together with the carbon atom to which they are bonded. Specific examples of such an aliphatic cyclic group include groups in which one or more hydrogen atoms have been removed from polycycloalkanes such as monocycloalkanes, bicycloalkanes, tricycloalkanes, and tetracycloalkanes. Specific examples include groups in which one or more hydrogen atoms have been removed from monocycloalkanes such as cyclopentane, cyclohexane, cycloheptane, and cyclooctane, and polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. In particular, groups in which one or more hydrogen atoms have been removed from cyclohexane and adamantane (which may further have a substituent) are preferred.

[0280] Furthermore, the above R 16b and R 17b When the aliphatic cyclic group formed by has a substituent on its ring skeleton, examples of the substituent include polar groups such as a hydroxyl group, a carboxyl group, a cyano group, and an oxygen atom (=O), and linear or branched alkyl groups having 1 to 4 carbon atoms. An oxygen atom (=O) is particularly preferred as the polar group.

[0281] Above Y bis an aliphatic cyclic group or an alkyl group, and examples thereof include groups in which one or more hydrogen atoms have been removed from polycycloalkanes such as monocycloalkanes, bicycloalkanes, tricycloalkanes, and tetracycloalkanes. Specific examples thereof include groups in which one or more hydrogen atoms have been removed from monocycloalkanes such as cyclopentane, cyclohexane, cycloheptane, and cyclooctane, and groups in which one or more hydrogen atoms have been removed from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. In particular, groups in which one or more hydrogen atoms have been removed from adamantane (which may further have a substituent) are preferred.

[0282] Furthermore, the above Y b When the aliphatic cyclic group has a substituent on its ring skeleton, examples of the substituent include polar groups such as a hydroxyl group, a carboxyl group, a cyano group, and an oxygen atom (=O), and linear or branched alkyl groups having 1 to 4 carbon atoms. An oxygen atom (=O) is particularly preferred as the polar group.

[0283] Also, Y b When is an alkyl group, it is preferably a straight-chain or branched alkyl group having from 1 to 20 carbon atoms, preferably from 6 to 15. Such an alkyl group is particularly preferably an alkoxyalkyl group, and examples of such an alkoxyalkyl group include a 1-methoxyethyl group, a 1-ethoxyethyl group, a 1-n-propoxyethyl group, a 1-isopropoxyethyl group, a 1-n-butoxyethyl group, a 1-isobutoxyethyl group, a 1-tert-butoxyethyl group, a 1-methoxypropyl group, a 1-ethoxypropyl group, a 1-methoxy-1-methyl-ethyl group, and a 1-ethoxy-1-methylethyl group.

[0284] Specific preferred examples of the structural unit represented by formula (b5) above include those represented by formulas (b5-1) to (b5-33) below.

[0285] [ka]

[0286] In the above formulas (b5-1) to (b5-33), R 24b represents a hydrogen atom or a methyl group.

[0287] Specific preferred examples of the structural unit represented by formula (b6) above include those represented by formulas (b6-1) to (b6-26) below.

[0288] [ka]

[0289] In the above formulas (b6-1) to (b6-26), R 24b represents a hydrogen atom or a methyl group.

[0290] Specific preferred examples of the structural unit represented by formula (b7) above include those represented by formulas (b7-1) to (b7-15) below.

[0291] [ka]

[0292] In the above formulas (b7-1) to (b7-15), R 24b represents a hydrogen atom or a methyl group.

[0293] Among the constitutional units represented by the formulas (b5) to (b7) described above, the constitutional unit represented by the formula (b6) is preferred because it is easy to synthesize and relatively easy to achieve high sensitivity. b is preferably an alkyl group; 19b and R 20b A structural unit in which one or both of the above are alkyl groups is preferred.

[0294] Furthermore, the acrylic resin (B3) is preferably a resin made of a copolymer containing structural units derived from a polymerizable compound having an ether bond, in addition to the structural units represented by the above formulas (b5) to (b7).

[0295] Examples of the polymerizable compound having an ether bond include radical polymerizable compounds such as (meth)acrylic acid derivatives having an ether bond and an ester bond, and specific examples include 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, methoxytriethylene glycol (meth)acrylate, 3-methoxybutyl (meth)acrylate, ethyl carbitol (meth)acrylate, phenoxypolyethylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, methoxypolypropylene glycol (meth)acrylate, and tetrahydrofurfuryl (meth)acrylate. The polymerizable compound having an ether bond is preferably 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, or methoxytriethylene glycol (meth)acrylate. These polymerizable compounds may be used alone or in combination of two or more.

[0296] Furthermore, the acrylic resin (B3) may contain other polymerizable compounds as structural units in order to appropriately control the physical and chemical properties of the resin. Examples of such polymerizable compounds include known radical polymerizable compounds and anion polymerizable compounds.

[0297] Examples of such polymerizable compounds include monocarboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid; dicarboxylic acids such as maleic acid, fumaric acid, and itaconic acid; methacrylic acid derivatives having a carboxy group and an ester bond such as 2-methacryloyloxyethyl succinic acid, 2-methacryloyloxyethyl maleic acid, 2-methacryloyloxyethyl phthalic acid, and 2-methacryloyloxyethyl hexahydrophthalic acid; (meth)acrylic acid alkyl esters such as methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, and cyclohexyl (meth)acrylate; and (meth)acrylic acid hydroxyalkyl esters such as 2-hydroxyethyl (meth)acrylate and 2-hydroxypropyl (meth)acrylate. esters; (meth)acrylic acid aryl esters such as phenyl (meth)acrylate and benzyl (meth)acrylate; dicarboxylic acid diesters such as diethyl maleate and dibutyl fumarate; vinyl group-containing aromatic compounds such as styrene, α-methylstyrene, chlorostyrene, chloromethylstyrene, vinyltoluene, hydroxystyrene, α-methylhydroxystyrene, and α-ethylhydroxystyrene; vinyl group-containing aliphatic compounds such as vinyl acetate; conjugated diolefins such as butadiene and isoprene; nitrile group-containing polymerizable compounds such as acrylonitrile and methacrylonitrile; chlorine-containing polymerizable compounds such as vinyl chloride and vinylidene chloride; and amide bond-containing polymerizable compounds such as acrylamide and methacrylamide.

[0298] As described above, the acrylic resin (B3) may contain a structural unit derived from a polymerizable compound having a carboxy group, such as the monocarboxylic acids and dicarboxylic acids. However, from the viewpoint of easily forming a resist pattern including a non-resist portion having a rectangular cross-sectional shape, it is preferable that the acrylic resin (B3) does not substantially contain a structural unit derived from a polymerizable compound having a carboxy group. Specifically, the ratio of the structural unit derived from a polymerizable compound having a carboxy group in the acrylic resin (B3) is preferably 20% by mass or less, more preferably 15% by mass or less, and particularly preferably 10% by mass or less. In the acrylic resin (B3), an acrylic resin containing a relatively large amount of structural units derived from a polymerizable compound having a carboxy group is preferably used in combination with an acrylic resin containing only a small amount of or no structural units derived from a polymerizable compound having a carboxy group.

[0299] Examples of the polymerizable compound include (meth)acrylic acid esters having an acid-non-dissociable aliphatic polycyclic group, vinyl group-containing aromatic compounds, etc. As the acid-non-dissociable aliphatic polycyclic group, tricyclodecanyl group, adamantyl group, tetracyclododecanyl group, isobornyl group, norbornyl group, etc. are particularly preferred in terms of industrial availability, etc. These aliphatic polycyclic groups may have a linear or branched alkyl group having 1 to 5 carbon atoms as a substituent.

[0300] Specific examples of the (meth)acrylic acid esters having an acid non-dissociable aliphatic polycyclic group include those having structures of the following formulae (b8-1) to (b8-5).

[0301] [ka]

[0302] In the above formulas (b8-1) to (b8-5), R 25b represents a hydrogen atom or a methyl group.

[0303] When the acrylic resin (B3) contains a structural unit (b-3) containing an -SO2--containing cyclic group or a lactone-containing cyclic group, the content of the structural unit (b-3) in the acrylic resin (B3) is preferably 5% by mass or more, more preferably 10% by mass or more, particularly preferably 10% by mass or more and 50% by mass or less, and most preferably 10% by mass or more and 30% by mass or less. When the photosensitive composition contains the structural unit (b-3) in an amount within the above range, it is easy to achieve both good developability and good pattern shape.

[0304] The acrylic resin (B3) preferably contains 5% by mass or more, more preferably 10% by mass or more, and particularly preferably 10% by mass or more and 50% by mass or less, of the structural units represented by the above formulas (b5) to (b7).

[0305] The acrylic resin (B3) preferably contains a structural unit derived from the polymerizable compound having an ether bond. The content of the structural unit derived from the polymerizable compound having an ether bond in the acrylic resin (B3) is preferably 0% by mass or more and 50% by mass or less, more preferably 5% by mass or more and 40% by mass or less, and even more preferably 5% by mass or more and 30% by mass or less.

[0306] The acrylic resin (B3) preferably contains a structural unit derived from a (meth)acrylic acid ester having an acid non-dissociable aliphatic polycyclic group. The content of the structural unit derived from a (meth)acrylic acid ester having an acid non-dissociable aliphatic polycyclic group in the acrylic resin (B3) is preferably 0% by mass or more and 60% by mass or less, more preferably 5% by mass or more and 50% by mass or less, and even more preferably 5% by mass or more and 30% by mass or less.

[0307] As long as the photosensitive composition contains a predetermined amount of the acrylic resin (B3), an acrylic resin other than the acrylic resin (B3) described above can also be used as the resin (B). Such an acrylic resin other than the acrylic resin (B3) is not particularly limited as long as it is a resin containing the structural units represented by the above formulas (b5) to (b7).

[0308] The polystyrene-equivalent weight average molecular weight of the resin (B) described above is preferably from 10,000 to 600,000, more preferably from 20,000 to 400,000, and even more preferably from 30,000 to 300,000. By setting the weight average molecular weight in this range, it is possible to maintain sufficient strength of the photosensitive layer made of the photosensitive composition without reducing the releasability from the substrate, and further to prevent swelling of the profile and the occurrence of cracks during plating.

[0309] The polydispersity of the resin (B) is preferably 1.05 or more. Here, the polydispersity is the value obtained by dividing the mass average molecular weight by the number average molecular weight. By setting the polydispersity in this range, it is possible to avoid the problem of the desired stress resistance to plating and the tendency of the metal layer obtained by plating to swell.

[0310] The content of the resin (B) is preferably from 5% by mass to 60% by mass based on the total mass of the photosensitive composition. The content of the resin (B) is preferably from 5 to 98% by mass, and more preferably from 10 to 95% by mass, based on the total solid content by mass of the photosensitive composition.

[0311] <Acid diffusion suppressant (C)> The acid diffusion inhibitor (C) contained in the photosensitive composition includes a compound represented by the following formula (C1). By including a compound represented by formula (C1) as the acid diffusion inhibitor (C), the photosensitive composition can easily form a resist pattern having a good cross-sectional rectangularity, and can provide a photosensitive composition with high resolution and dimensional controllability, as shown in the examples described later. Therefore, by using the photosensitive composition, a resist pattern having a desired shape and a rectangular cross-sectional shape can be formed. Regarding the cross-sectional shape, for example, in the vicinity of the contact surface between the substrate surface and the resist pattern, the resist portion is prevented from protruding toward the non-resist portion, resulting in a footing shape (a skirting shape) or a bite shape. The verticality of the cross-sectional shape of the resist pattern is also improved. [ka] (In formula (C1), R 1c is an alkyl group or an aralkyl group, R 2c is an alkyl group or an aralkyl group, R 3c is a hydrogen atom or an alkyl group, R 4cis a single bond or an alkylene group, n1 is an integer between 0 and 5, n2 is an integer between 0 and 5, n3 is 0 or 1. However, when n3 is 1, n1 and n2 cannot be 0 at the same time.)

[0312] In formula (C1), R 1c The alkyl group as may be linear or branched. The number of carbon atoms of the alkyl group is not particularly limited, but the number of carbon atoms is preferably 1 to 10, and more preferably 6 to 10. Specific examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, a sec-pentyl group, a tert-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, an isooctyl group, a sec-octyl group, a tert-octyl group, a 2-ethylhexyl group, an n-nonyl group, an isononyl group, and an n-decyl group. R 1c The alkylene group constituting the aralkyl group (aryl group-alkylene group) as the aryl group may be linear or branched. The number of carbon atoms in the aralkyl group is not particularly limited, but is preferably 6 to 20, more preferably 6 to 10. Specific examples of the aralkyl group include a benzyl group, a 1-phenylethyl group, a 2-phenylethyl group, a naphthalene-1-ylmethyl group, and a naphthalene-2-ylmethyl group. If n1 is an integer between 2 and 5, multiple R 1c may be the same or different. If n3 is 0, then two (R 1c ) n1 -C6H4-R 4c - may be the same or different. -C6H4- represents a phenylene group. In formula (C1), R 2c The alkyl group or aralkyl group represented by R in formula (C1) is 1c is the same as: If n2 is an integer between 2 and 5, multiple R 2c may be the same or different. R 1c and R 2c is preferably bulky and is preferably an alkyl group having 6 to 10 carbon atoms or an aralkyl group having 6 to 10 carbon atoms.

[0313] In formula (C1), R 3c The alkyl group as R may be linear or branched. The number of carbon atoms in the alkyl group is not particularly limited, but the number of carbon atoms is preferably 1 to 10, and more preferably 6 to 10. Specific examples of the alkyl group include R 1c The alkyl group is the same as the alkyl group represented by the formula (I).

[0314] In formula (C1), R 4c The alkylene group as may be linear or branched. The number of carbon atoms of the alkylene group is not particularly limited, but the number of carbon atoms is preferably 1 to 5, and more preferably 1 to 3. Specific examples of the alkylene group include a methylene group, an ethylene group, an n-propylene group, and an isopropylene group.

[0315] In the compound represented by formula (C1), n3 is 1, and R 4c In compounds where n is a single bond, n3 is 0, and R 4c is preferably an alkylene group.

[0316] The compound represented by formula (C1) is preferably used in an amount of 0.01 to 20 parts by mass, more preferably 0.01 to 5 parts by mass, and even more preferably 0.01 to 3 parts by mass, relative to 100 parts by mass of resin (B).

[0317] The acid diffusion inhibitor (C) may contain an acid diffusion inhibitor other than the compound represented by the above formula (C1). However, the content of the compound represented by the formula (C1) in the acid diffusion inhibitor (C) is preferably 50% by mass or more, more preferably 80% by mass or more, and even more preferably 100% by mass.

[0318] <Acid diffusion suppressor (C')> As the acid diffusion inhibitor other than the compound represented by formula (C1), a nitrogen-containing compound (C'1) other than the compound represented by formula (C1) is preferred, and if necessary, an organic carboxylic acid, or a phosphorus oxoacid or its derivative (C'2) can be further contained.

[0319] [Nitrogen-containing compounds (C'1)] Examples of the nitrogen-containing compound (C'1) include trimethylamine, diethylamine, triethylamine, di-n-propylamine, tri-n-propylamine, tri-n-pentylamine, tribenzylamine, diethanolamine, triethanolamine, n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, ethylenediamine, N,N,N',N'-tetramethylethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylether, 4,4'-diaminobenzophenone, 4,4'-diaminodiphenylamine, formamide, N-methylformamide, N,N- Examples of the monomer include dimethylformamide, acetamide, N-methylacetamide, N,N-dimethylacetamide, propionamide, benzamide, pyrrolidone, N-methylpyrrolidone, methylurea, 1,1-dimethylurea, 1,3-dimethylurea, 1,1,3,3,-tetramethylurea, 1,3-diphenylurea, imidazole, benzimidazole, 4-methylimidazole, 8-oxyquinoline, acridine, purine, pyrrolidine, piperidine, 2,4,6-tri(2-pyridyl)-S-triazine, morpholine, 4-methylmorpholine, piperazine, 1,4-dimethylpiperazine, 1,4-diazabicyclo[2.2.2]octane, pyridine, etc. These may be used alone or in combination of two or more.

[0320] In addition, commercially available hindered amine compounds such as ADK STAB LA-52, ADK STAB LA-57, ADK STAB LA-63P, ADK STAB LA-68, ADK STAB LA-72, ADK STAB LA-77Y, ADK STAB LA-77G, ADK STAB LA-81, ADK STAB LA-82, and ADK STAB LA-87 (all manufactured by ADEKA Corporation), and pyridines in which the 2,6-positions are substituted with substituents such as hydrocarbon groups, such as 2,6-diphenylpyridine and 2,6-di-tert-butylpyridine, can also be used as the nitrogen-containing compound (C'1).

[0321] The nitrogen-containing compound (C'1) is typically used in an amount of 0 to 5 parts by mass, and particularly preferably in an amount of 0 to 3 parts by mass, per 100 parts by mass of the combined mass of the resin (B) and the alkali-soluble resin (D).

[0322] [Organic carboxylic acids, phosphorus oxoacids or their derivatives (C'2)] Of the organic carboxylic acids or phosphorus oxoacids or derivatives thereof (C'2), specifically, suitable organic carboxylic acids include malonic acid, citric acid, malic acid, succinic acid, benzoic acid, salicylic acid, etc., with salicylic acid being particularly preferred.

[0323] Examples of phosphorus oxoacids or derivatives thereof include phosphoric acid, phosphoric acid di-n-butyl ester, phosphoric acid diphenyl ester, and other phosphoric acid and ester derivatives thereof; phosphonic acid, phosphonic acid dimethyl ester, phosphonic acid di-n-butyl ester, phenylphosphonic acid, phosphonic acid diphenyl ester, phosphonic acid dibenzyl ester, and other phosphonic acid and ester derivatives thereof; phosphinic acid, phosphinic acid phenylphosphinic acid, and other ester derivatives thereof; and the like. Among these, phosphonic acid is particularly preferred. These may be used alone or in combination of two or more.

[0324] The organic carboxylic acid, or phosphorus oxoacid or its derivative (C'2) is usually used in a range of 0 to 5 parts by mass, and particularly preferably in a range of 0 to 3 parts by mass, per 100 parts by mass of the combined mass of the resin (B) and the alkali-soluble resin (D).

[0325] In order to form a salt and stabilize the resulting mixture, it is preferable to use the organic carboxylic acid, or phosphorus oxoacid or its derivative (C'2) in an amount equivalent to that of the nitrogen-containing compound (C'1).

[0326] <Alkali-soluble resin (D)> The photosensitive composition preferably further contains an alkali-soluble resin (D) to improve crack resistance. Here, the alkali-soluble resin refers to a resin that dissolves to a depth of 0.01 μm or more when a resin film having a thickness of 1 μm is formed on a substrate using a resin solution having a resin concentration of 20% by mass (solvent: propylene glycol monomethyl ether acetate) and immersed in a 2.38% by mass TMAH aqueous solution for 1 minute. The alkali-soluble resin (D) is preferably at least one resin selected from the group consisting of novolac resin (D1), polyhydroxystyrene resin (D2), and acrylic resin (D3).

[0327] [Novolac resin (D1)] Novolak resins can be obtained, for example, by addition condensation of aromatic compounds having a phenolic hydroxyl group (hereinafter simply referred to as "phenols") with aldehydes in the presence of an acid catalyst.

[0328] 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, p-phenylphenol, resorcinol, hydroquinone, hydroquinone monomethyl ether, pyrogallol, phloroglucinol, hydroxydiphenyl, bisphenol A, gallic acid, gallic acid esters, α-naphthol, and β-naphthol. Examples of the aldehydes include formaldehyde, furfural, benzaldehyde, nitrobenzaldehyde, and acetaldehyde. The catalyst used in the addition condensation reaction is not particularly limited, but for example, hydrochloric acid, nitric acid, sulfuric acid, formic acid, oxalic acid, acetic acid, etc. are used as acid catalysts.

[0329] The flexibility of the novolak resin can be further improved by using o-cresol, substituting the hydrogen atoms of the hydroxyl groups in the resin with other substituents, or using bulky aldehydes.

[0330] The mass average molecular weight of the novolak resin (D1) is not particularly limited as long as it does not impair the object of the present invention, but is preferably 1,000 or more and 50,000 or less.

[0331] [Polyhydroxystyrene resin (D2)] Examples of the hydroxystyrene-based compound constituting the polyhydroxystyrene resin (D2) include p-hydroxystyrene, α-methylhydroxystyrene, and α-ethylhydroxystyrene. Furthermore, the polyhydroxystyrene resin (D2) is preferably a copolymer with a styrene resin. Examples of the styrene-based compound constituting such a styrene resin include styrene, chlorostyrene, chloromethylstyrene, vinyltoluene, and α-methylstyrene.

[0332] The mass average molecular weight of the polyhydroxystyrene resin (D2) is not particularly limited as long as it does not impair the object of the present invention, but is preferably 1,000 or more and 50,000 or less.

[0333] [Acrylic resin (D3)] The acrylic resin (D3) preferably contains a structural unit derived from a polymerizable compound having an ether bond, and a structural unit derived from a polymerizable compound having a carboxy group.

[0334] Examples of the polymerizable compound having an ether bond include (meth)acrylic acid derivatives having an ether bond and an ester bond, such as 2-methoxyethyl (meth)acrylate, methoxytriethylene glycol (meth)acrylate, 3-methoxybutyl (meth)acrylate, ethyl carbitol (meth)acrylate, phenoxypolyethylene glycol (meth)acrylate, methoxypolypropylene glycol (meth)acrylate, and tetrahydrofurfuryl (meth)acrylate. The polymerizable compound having an ether bond is preferably 2-methoxyethyl acrylate or methoxytriethylene glycol acrylate. These polymerizable compounds may be used alone or in combination of two or more.

[0335] Examples of the polymerizable compound having a carboxy group include monocarboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid; dicarboxylic acids such as maleic acid, fumaric acid, and itaconic acid; and compounds having a carboxy group and an ester bond such as 2-methacryloyloxyethyl succinic acid, 2-methacryloyloxyethyl maleic acid, 2-methacryloyloxyethyl phthalic acid, and 2-methacryloyloxyethyl hexahydrophthalic acid. The polymerizable compound having a carboxy group is preferably acrylic acid or methacrylic acid. These polymerizable compounds may be used alone or in combination of two or more.

[0336] The mass average molecular weight of the acrylic resin (D3) is not particularly limited as long as it does not impair the object of the present invention, but is preferably 50,000 or more and 800,000 or less.

[0337] The content of the alkali-soluble resin (D) is preferably 0 to 80 parts by mass, more preferably 0 to 60 parts by mass, when the total of the resin (B) and the alkali-soluble resin (D) is 100 parts by mass. By setting the content of the alkali-soluble resin (D) within the above range, crack resistance is improved and film loss during development tends to be prevented.

[0338] <Sulfur-containing compounds (E)> When the photosensitive composition is used for forming a pattern on a metal substrate, the photosensitive composition preferably contains a sulfur-containing compound (E). The sulfur-containing compound (E) is a compound containing a sulfur atom that can be coordinated to a metal. In addition, regarding a compound that can produce two or more tautomers, if at least one tautomer contains a sulfur atom that can be coordinated to a metal that constitutes the surface of a metal substrate, the compound corresponds to a sulfur-containing compound. When a resist pattern used as a plating mold is formed on a surface made of a metal such as Cu, defects in the cross-sectional shape such as footing may occur. As described above, when the above-mentioned photosensitive composition is used, it is easy to form a resist pattern with good rectangularity in the cross-sectional shape. On the other hand, in order to more reliably suppress defects in the cross-sectional shape, it is preferable that the photosensitive composition contains a sulfur-containing compound (E). When the photosensitive composition contains a sulfur-containing compound (E), it is easier to more reliably suppress the occurrence of defects in the cross-sectional shape such as footing, even when a resist pattern is formed on a surface made of a metal in a substrate. When the photosensitive composition is used for pattern formation on a substrate other than a metal substrate, the photosensitive composition does not need to contain a sulfur-containing compound.When the photosensitive composition is used for pattern formation on a substrate other than a metal substrate, the photosensitive composition preferably does not contain a sulfur-containing compound (E) because the number of components in the photosensitive composition is reduced, making the photosensitive composition easier to manufacture and reducing the manufacturing cost of the photosensitive composition. Incidentally, there is no particular problem caused by the inclusion of the sulfur-containing compound (E) in a photosensitive composition used for forming a pattern on a substrate other than a metal substrate.

[0339] The sulfur atom capable of coordinating to a metal is contained in the sulfur-containing compound as, for example, a mercapto group (-SH), a thiocarboxy group (-CO-SH), a dithiocarboxy group (-CS-SH), a thiocarbonyl group (-CS-), and the like. The sulfur-containing compound preferably has a mercapto group, since this group is easily coordinated to metals and has an excellent effect of suppressing footing.

[0340] A preferred example of the sulfur-containing compound having a mercapto group is a compound represented by the following formula (e1). [ka] (In the formula, R e1 and R e2 each independently represents a hydrogen atom or an alkyl group; R e3 represents a single bond or an alkylene group, R e4 represents an aliphatic group having a valence of u which may contain atoms other than carbon, and u represents an integer of 2 to 4.

[0341] R e1 and R e2 When R is an alkyl group, the alkyl group may be linear or branched, and is preferably linear. e1 and R e2 When R is an alkyl group, the number of carbon atoms in the alkyl group is not particularly limited as long as it does not impair the object of the present invention. The number of carbon atoms in the alkyl group is preferably 1 or more and 4 or less, more preferably 1 or 2, and most preferably 1. e1 and R e2 As for the combination of these, one is preferably a hydrogen atom and the other an alkyl group, and particularly preferably one is a hydrogen atom and the other a methyl group.

[0342] R e3 When R is an alkylene group, the alkylene group may be linear or branched, and is preferably linear. e3 When is an alkylene group, the number of carbon atoms of the alkylene group is not particularly limited as long as it does not impair the object of the present invention. The number of carbon atoms of the alkylene group is preferably 1 to 10, more preferably 1 to 5, particularly preferably 1 or 2, and most preferably 1.

[0343] R e4 R is a divalent to tetravalent aliphatic group which may contain atoms other than carbon. e4Examples of atoms other than carbon that may be contained in R include a nitrogen atom, an oxygen atom, a sulfur atom, a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. e4 The structure of the aliphatic group may be linear, branched, or cyclic, or may be a combination of these structures.

[0344] Among the compounds represented by formula (e1), a compound represented by the following formula (e2) is more preferred. [ka] (In formula (e2), R e4 and u are the same as in formula (e1).

[0345] Among the compounds represented by the above formula (e2), the following compounds are preferred. [ka]

[0346] Compounds represented by the following formulae (e3-L1) to (e3-L7) are also preferred examples of the sulfur-containing compound having a mercapto group. [ka] (In formulae (e3-L1) to (e3-L7), R', s", A", and r are the same as those in formulae (b-L1) to (b-L7) described above for the acrylic resin (B3).)

[0347] Preferred specific examples of the mercapto compounds represented by the above formulas (e3-L1) to (e3-L7) include the following compounds. [ka]

[0348] Compounds represented by the following formulas (e3-1) to (e3-4) are also preferred examples of the sulfur-containing compound having a mercapto group. [ka] (The definitions of the abbreviations in the formulae (e3-1) to (e3-4) are as described above for the acrylic resin (B3) and for the formulae (3-1) to (3-4).)

[0349] Preferred specific examples of the mercapto compounds represented by the above formulas (e3-1) to (e3-4) include the following compounds.

[0350] [ka]

[0351] Moreover, a suitable example of the compound having a mercapto group is a compound represented by the following formula (e4). [ka] (In formula (e4), R e5 is a group selected from the group consisting of a hydroxyl group, an alkyl group having from 1 to 4 carbon atoms, an alkoxy group having from 1 to 4 carbon atoms, an alkylthio group having from 1 to 4 carbon atoms, a hydroxyalkyl group having from 1 to 4 carbon atoms, a mercaptoalkyl group having from 1 to 4 carbon atoms, a halogenated alkyl group having from 1 to 4 carbon atoms, and a halogen atom; n1 is an integer of 0 to 3, n0 is an integer of 0 to 3; when n1 is 2 or 3, R e5 may be the same or different.)

[0352] R e5 Specific examples of the alkyl group having 1 to 4 carbon atoms which may have a hydroxyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a tert-butyl group. Among these alkyl groups, a methyl group, a hydroxymethyl group, and an ethyl group are preferred.

[0353] R e5Specific examples of when is an alkoxy group having 1 to 4 carbon atoms include a methoxy group, an ethoxy group, an n-propyloxy group, an isopropyloxy group, an n-butyloxy group, an isobutyloxy group, a sec-butyloxy group, and a tert-butyloxy group. Among these alkoxy groups, a methoxy group and an ethoxy group are preferred, and a methoxy group is more preferred.

[0354] R e5 Specific examples of when is an alkylthio group having 1 to 4 carbon atoms include a methylthio group, an ethylthio group, an n-propylthio group, an isopropylthio group, an n-butylthio group, an isobutylthio group, a sec-butylthio group, and a tert-butylthio group. Among these alkylthio groups, a methylthio group and an ethylthio group are preferred, and a methylthio group is more preferred.

[0355] R e5 Specific examples of the hydroxyalkyl group having 1 to 4 carbon atoms include a hydroxymethyl group, a 2-hydroxyethyl group, a 1-hydroxyethyl group, a 3-hydroxy-n-propyl group, and a 4-hydroxy-n-butyl group. Among these hydroxyalkyl groups, a hydroxymethyl group, a 2-hydroxyethyl group, and a 1-hydroxyethyl group are preferred, and a hydroxymethyl group is more preferred.

[0356] R e5 Specific examples of the mercaptoalkyl group having 1 to 4 carbon atoms include a mercaptomethyl group, a 2-mercaptoethyl group, a 1-mercaptoethyl group, a 3-mercapto-n-propyl group, and a 4-mercapto-n-butyl group. Among these mercaptoalkyl groups, a mercaptomethyl group, a 2-mercaptoethyl group, and a 1-mercaptoethyl group are preferred, and a mercaptomethyl group is more preferred.

[0357] R e5 When R is a halogenated alkyl group having 1 to 4 carbon atoms, examples of the halogen atom contained in the halogenated alkyl group include fluorine, chlorine, bromine, and iodine.e5 Specific examples of the halogenated alkyl group having 1 to 4 carbon atoms include a chloromethyl group, a bromomethyl group, an iodomethyl group, a fluoromethyl group, a dichloromethyl group, a dibromomethyl group, a difluoromethyl group, a trichloromethyl group, a tribromomethyl group, a trifluoromethyl group, a 2-chloroethyl group, a 2-bromoethyl group, a 2-fluoroethyl group, a 1,2-dichloroethyl group, a 2,2-difluoroethyl group, a 1-chloro-2-fluoroethyl group, a 3-chloro-n-propyl group, a 3-bromo-n-propyl group, a 3-fluoro-n-propyl group, and a 4-chloro-n-butyl group. Among these halogenated alkyl groups, a chloromethyl group, a bromomethyl group, an iodomethyl group, a fluoromethyl group, a dichloromethyl group, a dibromomethyl group, a difluoromethyl group, a trichloromethyl group, a tribromomethyl group, and a trifluoromethyl group are preferred, and a chloromethyl group, a dichloromethyl group, a trichloromethyl group, and a trifluoromethyl group are more preferred.

[0358] R e5 Specific examples of when is a halogen atom include fluorine, chlorine, bromine, and iodine.

[0359] In formula (e4), n1 is an integer of 0 to 3, and more preferably 1. When n1 is 2 or 3, a plurality of R e5 may be the same or different.

[0360] In the compound represented by formula (e4), R on the benzene ring e5 The substitution position of R on the benzene ring is not particularly limited. e5 The substitution position is -(CH2) n0 It is preferably in the meta or para position relative to the bonding position of --SH.

[0361] The compound represented by formula (e4) is R e5 As R, a compound having at least one group selected from the group consisting of an alkyl group, a hydroxyalkyl group, and a mercaptoalkyl group is preferred. e5More preferably, the compound represented by formula (e4) has one group selected from the group consisting of an alkyl group, a hydroxyalkyl group, and a mercaptoalkyl group as R e5 When the alkyl group has one group selected from the group consisting of an alkyl group, a hydroxyalkyl group, and a mercaptoalkyl group, the substitution position of the alkyl group, the hydroxyalkyl group, or the mercaptoalkyl group on the benzene ring is -(CH2) n0 It is preferably at the meta or para position relative to the bonding position of --SH, and more preferably at the para position.

[0362] In formula (e4), n0 is an integer of 0 to 3. In terms of ease of preparation and availability of the compound, n0 is preferably 0 or 1, and more preferably 0.

[0363] Specific examples of the compound represented by formula (e4) include p-mercaptophenol, p-thiocresol, m-thiocresol, 4-(methylthio)benzenethiol, 4-methoxybenzenethiol, 3-methoxybenzenethiol, 4-ethoxybenzenethiol, 4-isopropyloxybenzenethiol, 4-tert-butoxybenzenethiol, 3,4-dimethoxybenzenethiol, 3,4,5-trimethoxybenzenethiol, 4-ethylbenzenethiol, 4-isopropylbenzenethiol, 4-n-butylbenzenethiol, 4 -tert-Butylbenzenethiol, 3-ethylbenzenethiol, 3-isopropylbenzenethiol, 3-n-butylbenzenethiol, 3-tert-butylbenzenethiol, 3,5-dimethylbenzenethiol, 3,4-dimethylbenzenethiol, 3-tert-butyl-4-methylbenzenethiol, 3-tert-4-methylbenzenethiol, 3-tert-butyl-5-methylbenzenethiol, 4-tert-butyl-3-methylbenzenethiol, 4-mercaptobenzyl alcohol, 3-mercaptobenzyl alcohol benzenethiol, 4-(mercaptomethyl)phenol, 3-(mercaptomethyl)phenol, 1,4-di(mercaptomethyl)phenol, 1,3-di(mercaptomethyl)phenol, 4-fluorobenzenethiol, 3-fluorobenzenethiol, 4-chlorobenzenethiol, 3-chlorobenzenethiol, 4-bromobenzenethiol, 4-iodobenzenethiol, 3-bromobenzenethiol, 3,4-dichlorobenzenethiol, 3,5-dichlorobenzenethiol, 3,4-difluorobenzenethiol, 3,5-difluorobenzenethiol thiol, 4-mercaptocatechol, 2,6-di-tert-butyl-4-mercaptophenol, 3,5-di-tert-butyl-4-methoxybenzenethiol, 4-bromo-3-methylbenzenethiol, 4-(trifluoromethyl)benzenethiol, 3-(trifluoromethyl)benzenethiol, 3,5-bis(trifluoromethyl)benzenethiol, 4-methylthiobenzenethiol, 4-ethylthiobenzenethiol, 4-n-butylthiobenzenethiol, and 4-tert-butylthiobenzenethiol.

[0364] Examples of the sulfur-containing compound having a mercapto group include a compound containing a nitrogen-containing aromatic heterocycle substituted with a mercapto group, and a tautomer of a compound containing a nitrogen-containing aromatic heterocycle substituted with a mercapto group. Specific preferred examples of the nitrogen-containing aromatic heterocycle include imidazole, pyrazole, 1,2,3-triazole, 1,2,4-triazole, oxazole, thiazole, pyridine, pyrimidine, pyridazine, pyrazine, 1,2,3-triazine, 1,2,4-triazine, 1,3,5-triazine, indole, indazole, benzimidazole, benzoxazole, benzothiazole, 1H-benzotriazole, quinoline, isoquinoline, cinnoline, phthalazine, quinazoline, quinoxaline, and 1,8-naphthyridine.

[0365] Specific examples of suitable nitrogen-containing heterocyclic compounds as the sulfur-containing compound and suitable tautomers of the nitrogen-containing heterocyclic compounds include the following compounds. [ka]

[0366] When the photosensitive composition contains the sulfur-containing compound (E), the amount used is preferably from 0.01 to 5 parts by mass, more preferably from 0.02 to 3 parts by mass, and particularly preferably from 0.05 to 2 parts by mass, per 100 parts by mass of the combined mass of the resin (B) and the alkali-soluble resin (D).

[0367] <Organic solvent (S)> The photosensitive composition contains an organic solvent (S). The type of organic solvent (S) is not particularly limited as long as it does not impair the object of the present invention, and may be appropriately selected from organic solvents that have been conventionally used in photosensitive compositions.

[0368] Specific examples of the organic solvent (S) include ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl isoamyl ketone, and 2-heptanone; polyhydric alcohols and derivatives thereof such as ethylene glycol, ethylene glycol monoacetate, diethylene glycol, diethylene glycol monoacetate, propylene glycol, propylene glycol monoacetate, dipropylene glycol, and monomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether, and monophenyl ether of dipropylene glycol monoacetate; and cyclic ethers such as dioxane. esters such as ethyl formate, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, methyl acetoacetate, ethyl acetoacetate, ethyl pyruvate, ethyl ethoxyacetate, methyl methoxypropionate, ethyl ethoxypropionate, methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, methyl 2-hydroxy-3-methylbutanoate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, etc.; aromatic hydrocarbons such as toluene and xylene; etc. These may be used alone or in combination of two or more.

[0369] The content of the organic solvent (S) is not particularly limited as long as it does not impair the object of the present invention. When the photosensitive composition is used for a thick film application in which the thickness of the photosensitive layer obtained by a spin coating method or the like is 5 μm or more, it is preferable to use the organic solvent (S) in such a range that the solid content concentration of the photosensitive composition is 30 mass % or more and 55 mass % or less.

[0370] <Other ingredients> The photosensitive composition may further contain a polyvinyl resin to improve plasticity. Specific examples of the polyvinyl resin include polyvinyl chloride, polystyrene, polyhydroxystyrene, polyvinyl acetate, polyvinyl benzoic acid, polyvinyl methyl ether, polyvinyl ethyl ether, polyvinyl alcohol, polyvinyl pyrrolidone, polyvinyl phenol, and copolymers thereof. The polyvinyl resin is preferably polyvinyl methyl ether in view of its low glass transition point.

[0371] The photosensitive composition preferably contains a Lewis acid compound. By containing a Lewis acid compound in the photosensitive composition, a highly sensitive photosensitive composition is easily obtained, and a resist pattern having a rectangular cross-sectional shape is more easily formed using the photosensitive composition. In addition, when a pattern is formed using a photosensitive composition, if the time required for each step in forming the pattern or the time required between each step is long, adverse effects such as difficulty in forming a pattern of the desired shape or dimensions, deterioration of developability, etc. However, by blending a Lewis acid compound in the photosensitive composition, such adverse effects on the pattern shape and developability can be alleviated, and the process margin can be widened.

[0372] Here, the Lewis acid compound means "a compound that has a vacant orbital capable of accepting at least one electron pair and acts as an electron pair acceptor." The Lewis acid compound is not particularly limited as long as it meets the above definition and is recognized as a Lewis acid compound by those skilled in the art. As the Lewis acid compound, a compound that does not fall under the category of a Bronsted acid (protonic acid) is preferably used. Specific examples of Lewis acid compounds include boron fluoride, boron fluoride ether complexes (e.g., BF3·Et2O, BF3·Me2O, BF3·THF, etc., where Et is an ethyl group, Me is a methyl group, and THF is tetrahydrofuran), organic boron compounds (e.g., tri-n-octyl borate, tri-n-butyl borate, triphenyl borate, and triphenyl boron, etc.), titanium chloride, aluminum chloride, aluminum bromide, and gallium chloride. Examples of the metal ions that can be used include tin, gallium bromide, indium chloride, thallium trifluoroacetate, tin chloride, zinc chloride, zinc bromide, zinc iodide, zinc trifluoromethanesulfonate, zinc acetate, zinc nitrate, zinc tetrafluoroborate, manganese chloride, manganese bromide, nickel chloride, nickel bromide, nickel cyanide, nickel acetylacetonate, cadmium chloride, cadmium bromide, stannous chloride, stannous bromide, stannous sulfate, and stannous tartrate. Other specific examples of Lewis acidic compounds include chlorides, bromides, sulfates, nitrates, carboxylates, and trifluoromethanesulfonates of rare earth metal elements, cobalt chloride, ferrous chloride, and yttrium chloride. Here, examples of rare earth metal elements include lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium.

[0373] The Lewis acid compound preferably contains a Lewis acid compound containing an element of Group 13 of the periodic table, since it is easily available and the effect of its addition is good. Here, the Group 13 elements of the periodic table include boron, aluminum, gallium, indium, and thallium. Among the above-mentioned elements of Group 13 of the periodic table, boron is preferred because of the ease of availability of Lewis acid compounds and the particularly excellent effect of adding it, i.e., the Lewis acid compound preferably contains a Lewis acid compound containing boron.

[0374] Examples of Lewis acid compounds containing boron include boron halides such as boron fluoride, ether complexes of boron fluoride, boron chloride, and boron bromide, as well as various organic boron compounds. As Lewis acid compounds containing boron, organic boron compounds are preferred because they have a low content of halogen atoms and are therefore easy to apply to applications in which a low halogen content is required for the photosensitive composition.

[0375] A preferred example of the organic boron compound is represented by the following formula (f1): B(R f1 ) t1 (OR f2 ) (3-t1) (f1) (In formula (f1), R f1 and R f2 are each independently a hydrocarbon group having 1 to 20 carbon atoms, and the hydrocarbon group may have one or more substituents; t1 is an integer of 0 to 3; R f1 If there are multiple R f1 two of the groups may be bonded together to form a ring, and OR f2 If multiple exists, multiple OR f2 Two of the may be bonded to each other to form a ring. The photosensitive composition preferably contains, as a Lewis acid compound, at least one of the boron compounds represented by the above formula (f1).

[0376] In formula (f1), R f1 and R f2 When is a hydrocarbon group, the number of carbon atoms in the hydrocarbon group is from 1 to 20. The hydrocarbon group having from 1 to 20 carbon atoms may be an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a hydrocarbon group consisting of a combination of an aliphatic group and an aromatic group. The hydrocarbon group having 1 to 20 carbon atoms is preferably a saturated aliphatic hydrocarbon group or an aromatic hydrocarbon group. f1 and R f2The number of carbon atoms in the hydrocarbon group as the alkyl group is preferably 1 or more and 10 or less. When the hydrocarbon group is an aliphatic hydrocarbon group, the number of carbon atoms therein is more preferably 1 or more and 6 or less, and particularly preferably 1 or more and 4 or less. R f1 and R f2 The hydrocarbon group as may be a saturated or unsaturated hydrocarbon group, and is preferably a saturated hydrocarbon group. R f1 and R f2 When the hydrocarbon group as the alkyl group is an aliphatic hydrocarbon group, the aliphatic hydrocarbon group may be linear, branched, or cyclic, or may be a combination of these structures.

[0377] Specific examples of suitable aromatic hydrocarbon groups include a phenyl group, a naphthalene-1-yl group, a naphthalene-2-yl group, a 4-phenylphenyl group, a 3-phenylphenyl group, and a 2-phenylphenyl group. Of these, a phenyl group is preferred.

[0378] The saturated aliphatic hydrocarbon group is preferably an alkyl group. Specific examples of suitable alkyl groups include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, a 2-ethylhexyl group, an n-nonyl group, and an n-decyl group.

[0379] R f1 and R f2The hydrocarbon group as may have one or more substituents. Examples of the substituents include a halogen atom, a hydroxyl group, an alkyl group, an aralkyl group, an alkoxy group, a cycloalkyloxy group, an aryloxy group, an aralkyloxy group, an alkylthio group, a cycloalkylthio group, an arylthio group, an aralkylthio group, an acyl group, an acyloxy group, an acylthio group, an alkoxycarbonyl group, a cycloalkyloxycarbonyl group, an aryloxycarbonyl group, an amino group, an N-monosubstituted amino group, an N,N-disubstituted amino group, a carbamoyl group (-CO-NH2), an N-monosubstituted carbamoyl group, an N,N-disubstituted carbamoyl group, a nitro group, and a cyano group. The number of carbon atoms of the substituent is not particularly limited as long as it does not impair the object of the present invention, but is preferably 1 or more and 10 or less, and more preferably 1 or more and 6 or less.

[0380] Specific examples of suitable organoboron compounds represented by the above formula (f1) include the following compounds: In the following formula, Pen represents a pentyl group, Hex represents a hexyl group, Hep represents a heptyl group, Oct represents an octyl group, Non represents a nonyl group, and Dec represents a decyl group.

[0381] [ka]

[0382] [ka]

[0383] [ka]

[0384] [ka]

[0385] [ka]

[0386] The Lewis acid compound is preferably used in an amount of 0.01 to 5 parts by mass, more preferably 0.01 to 3 parts by mass, and even more preferably 0.05 to 2 parts by mass, relative to 100 parts by mass of the combined mass of the resin (B) and the alkali-soluble resin (D).

[0387] In addition, when the photosensitive composition is used to form a pattern that will serve as a mold for forming a plated object, the photosensitive composition may further contain an adhesion aid to improve adhesion between the mold formed using the photosensitive composition and a metal substrate.

[0388] The photosensitive composition may further contain a surfactant in order to improve coating properties, defoaming properties, leveling properties, etc. As the surfactant, for example, a fluorine-based surfactant or a silicone-based surfactant is preferably used. Specific examples of fluorine-based surfactants include commercially available fluorine-based surfactants such as BM-1000, BM-1100 (all manufactured by BM Chemie), Megafac F142D, Megafac F172, Megafac F173, Megafac F183 (all manufactured by Dainippon Ink and Chemicals), Fluorad FC-135, Fluorad FC-170C, Fluorad FC-430, Fluorad FC-431 (all manufactured by Sumitomo 3M), Surflon S-112, Surflon S-113, Surflon S-131, Surflon S-141, Surflon S-145 (all manufactured by Asahi Glass Co., Ltd.), SH-28PA, SH-190, SH-193, SZ-6032, and SF-8428 (all manufactured by Toray Silicones), but are not limited to these. As the silicone surfactant, an unmodified silicone surfactant, a polyether-modified silicone surfactant, a polyester-modified silicone surfactant, an alkyl-modified silicone surfactant, an aralkyl-modified silicone surfactant, a reactive silicone surfactant, and the like can be preferably used. As the silicone surfactant, commercially available silicone surfactants can be used. Specific examples of commercially available silicone surfactants include Paintad M (manufactured by Toray Dow Corning Co., Ltd.), Topika K1000, Topika K2000, Topika K5000 (all manufactured by Takachiho Sangyo Co., Ltd.), XL-121 (polyether-modified silicone surfactant, manufactured by Clariant), and BYK-310 (polyester-modified silicone surfactant, manufactured by BYK-Chemie Co., Ltd.).

[0389] The photosensitive composition may further contain an acid, an acid anhydride, or a high-boiling point solvent in order to finely adjust the solubility in the developer.

[0390] Specific examples of acids and acid anhydrides include monocarboxylic acids such as acetic acid, propionic acid, n-butyric acid, isobutyric acid, n-valeric acid, isovaleric acid, benzoic acid, and cinnamic acid; hydroxymonocarboxylic acids such as lactic acid, 2-hydroxybutyric acid, 3-hydroxybutyric acid, salicylic acid, m-hydroxybenzoic acid, p-hydroxybenzoic acid, 2-hydroxycinnamic acid, 3-hydroxycinnamic acid, 4-hydroxycinnamic acid, 5-hydroxyisophthalic acid, and syringic acid; oxalic acid, succinic acid, glutaric acid, adipic acid, maleic acid, itaconic acid, hexahydrophthalic acid, phthalic acid, isophthalic acid, terephthalic acid, 1,2-cyclohexanedicarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, butanetetracarboxylic acid, and trimellitic acid. Examples of the acid anhydride include polyvalent carboxylic acids such as itaconic anhydride, pyromellitic anhydride, cyclopentanetetracarboxylic acid, butanetetracarboxylic acid, and 1,2,5,8-naphthalenetetracarboxylic acid; and acid anhydrides such as itaconic anhydride, succinic anhydride, citraconic anhydride, dodecenylsuccinic anhydride, tricarbanilic anhydride, maleic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, himic anhydride, 1,2,3,4-butanetetracarboxylic anhydride, cyclopentanetetracarboxylic dianhydride, phthalic anhydride, pyromellitic anhydride, trimellitic anhydride, benzophenonetetracarboxylic anhydride, ethylene glycol bistrimellitate anhydride, and glycerin tristrimellitate anhydride.

[0391] Specific examples of high-boiling point solvents include N-methylformamide, N,N-dimethylformamide, N-methylformanilide, N-methylacetamide, N,N-dimethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide, benzyl ethyl ether, dihexyl ether, acetonylacetone, isophorone, caproic acid, caprylic acid, 1-octanol, 1-nonanol, benzyl alcohol, benzyl acetate, ethyl benzoate, diethyl oxalate, diethyl maleate, γ-butyrolactone, ethylene carbonate, propylene carbonate, and phenyl cellosolve acetate.

[0392] The photosensitive composition may further contain a well-known sensitizer to improve the sensitivity.

[0393] <Method for preparing chemically amplified positive-type photosensitive composition> The chemically amplified positive photosensitive composition is prepared by mixing and stirring the components of the composition in a normal manner. Examples of devices that can be used when mixing and stirring the above components include a dissolver, a homogenizer, and a three-roll mill. After the above components are mixed uniformly, the resulting mixture may be further filtered using a mesh, a membrane filter, or the like.

[0394] <Photosensitive dry film> The photosensitive dry film has a substrate film and a photosensitive layer formed on the surface of the substrate film. In the photosensitive dry film, the photosensitive layer is made of the above-mentioned photosensitive composition.

[0395] The substrate film is preferably a film having optical transparency, specifically, a polyethylene terephthalate (PET) film, a polypropylene (PP) film, a polyethylene (PE) film, etc., and the polyethylene terephthalate (PET) film is preferred because of its excellent balance between optical transparency and breaking strength.

[0396] The above-mentioned photosensitive composition is applied onto a substrate film to form a photosensitive layer, thereby producing a photosensitive dry film. When forming a photosensitive layer on a substrate film, a photosensitive composition is applied onto the substrate film using an applicator, a bar coater, a wire bar coater, a roll coater, a curtain flow coater, or the like, so that the film thickness after drying is preferably 0.5 μm or more and 300 μm or less, more preferably 1 μm or more and 300 μm or less, and particularly preferably 3 μm or more and 100 μm or less, and then dried.

[0397] The photosensitive dry film may further have a protective film on the photosensitive layer, such as a polyethylene terephthalate (PET) film, a polypropylene (PP) film, or a polyethylene (PE) film.

[0398] <Patterned resist film> The method for forming a patterned resist film on a substrate using the above-described photosensitive composition is not particularly limited. Such a patterned resist film is suitably used as an insulating film, an etching mask, a mold for forming a plating object, and the like. A preferred method is as follows: a lamination step of laminating a photosensitive layer made of a photosensitive composition on a substrate; an exposure step of exposing the photosensitive layer to actinic rays or radiation in a position-selective manner; a developing step of developing the exposed photosensitive layer; The present invention relates to a method for producing a patterned resist film, comprising the steps of: The manufacturing method of a mold-bearing substrate having a mold for forming a plated object is similar to the manufacturing method of a patterned resist film, except that it includes a step of laminating a photosensitive layer on the metal surface of a substrate having a metal surface, and a developing step of producing a mold for forming a plated object by development.

[0399] The substrate on which the photosensitive layer is laminated is not particularly limited, and any conventionally known substrate can be used, such as a substrate for electronic components, a substrate on which a predetermined wiring pattern is formed, etc. As the substrate, a silicon substrate, a glass substrate, etc. can also be used. When manufacturing a template-attached substrate having a template for forming a plated object, a substrate having a metal surface is used as the substrate. The metal species constituting the metal surface is preferably copper, gold, or aluminum, and more preferably copper.

[0400] The photosensitive layer is laminated on the substrate, for example, as follows. That is, a liquid photosensitive composition is applied onto the substrate, and the solvent is removed by heating to form a photosensitive layer with a desired thickness. The thickness of the photosensitive layer is not particularly limited as long as the resist pattern can be formed with a desired thickness. The thickness of the photosensitive layer is not particularly limited, but is preferably 0.5 μm or more, more preferably 0.5 μm to 300 μm, even more preferably 0.5 μm to 200 μm, and particularly preferably 0.5 μm to 150 μm.

[0401] The photosensitive composition can be applied to a substrate by a method such as spin coating, slit coating, roll coating, screen printing, or applicator. It is preferable to prebake the photosensitive layer. The prebake conditions vary depending on the type and blending ratio of each component in the photosensitive composition, the coating film thickness, etc., but are usually 70°C to 200°C, preferably 80°C to 150°C, and 2 minutes to 120 minutes.

[0402] The photosensitive layer formed as described above is selectively irradiated (exposed) with actinic rays or radiation, for example, ultraviolet rays or visible rays having a wavelength of 300 nm or more and 500 nm or less, through a mask having a predetermined pattern.

[0403] Examples of radiation sources that can be used include low-pressure mercury lamps, high-pressure mercury lamps, ultra-high pressure mercury lamps, metal halide lamps, and argon gas lasers. Examples of radiation include microwaves, infrared rays, visible light, ultraviolet rays, X-rays, gamma rays, electron beams, proton beams, neutron beams, and ion beams. The radiation dose varies depending on the composition of the photosensitive composition and the film thickness of the photosensitive layer, but for example, when an ultra-high pressure mercury lamp is used, it is 100 mJ / cm. 2 More than 10000mJ / cm 2 Radiation also includes light rays that activate the acid generator (A) to generate an acid.

[0404] After exposure, the photosensitive layer is heated using a known method to promote diffusion of the acid, thereby changing the solubility of the photosensitive layer in a developer such as an alkaline developer in the exposed parts of the photosensitive resin film.

[0405] The exposed photosensitive layer is then developed by a conventional method to dissolve and remove unnecessary portions, thereby forming a desired resist pattern or a mold for forming a plating object. In this case, an alkaline aqueous solution is used as the developer.

[0406] Examples of the developer include aqueous solutions of alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, aqueous ammonia, ethylamine, n-propylamine, diethylamine, di-n-propylamine, triethylamine, methyldiethylamine, dimethylethanolamine, triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, pyrrole, piperidine, 1,8-diazabicyclo[5,4,0]-7-undecene, and 1,5-diazabicyclo[4,3,0]-5-nonane. Alternatively, an aqueous solution of the above-mentioned alkalis to which an appropriate amount of a water-soluble organic solvent such as methanol or ethanol or a surfactant has been added can be used as the developer. Depending on the composition of the photosensitive composition, development using an organic solvent may also be applied.

[0407] The development time varies depending on the composition of the photosensitive composition, the thickness of the photosensitive layer, etc., but is usually from 1 minute to 30 minutes. The development method may be any of a puddle method, a dipping method, a puddle method, a spray development method, etc.

[0408] After the development, the substrate is washed with running water for 30 to 90 seconds, and then dried using an air gun, an oven, or the like. In this manner, a resist pattern having a desired shape is formed on the surface of the substrate. In addition, in this manner, a substrate having a mold, which is provided with a resist pattern serving as a mold on the metal surface of a substrate having a metal surface, can be produced.

[0409] The above-mentioned photosensitive composition has high resolution and dimensional controllability. In addition, the above-mentioned photosensitive composition is easy to form a resist pattern having a good rectangular cross-sectional shape. Therefore, a resist pattern having a desired shape and a high definition rectangular cross-sectional shape can be formed.

[0410] By embedding a conductor such as metal by plating in the non-resist portion (the portion removed by the developer) in the mold of the mold-attached substrate formed by the above method, it is possible to form a plated object such as a connection terminal such as a bump or a metal post, or a Cu rewiring. The plating method is not particularly limited, and various conventionally known methods can be adopted. As the plating solution, in particular, a solder plating, copper plating, gold plating, or nickel plating solution is preferably used. Finally, the remaining mold is removed using a stripping solution or the like according to a conventional method.

[0411] When manufacturing a plated object, it may be preferable to perform an ashing treatment on the metal surface exposed in the non-patterned portion of the resist pattern that serves as a mold for forming the plated object. Specifically, for example, a pattern formed using a photosensitive composition containing a sulfur-containing compound (E) is used as a mold to form a plated object. In this case, the adhesion of the plated object to the metal surface may be easily impaired. This problem is significant when the sulfur-containing compound (E) represented by the above formula (e1) or the sulfur-containing compound (E) represented by the formula (e4) is used. However, when the above-mentioned ashing treatment is performed, even if a pattern formed using a photosensitive composition containing the sulfur-containing compound (E) is used as a mold, a plated object that adheres well to the metal surface is easily formed. When a compound containing a nitrogen-containing aromatic heterocycle substituted with a mercapto group is used as the sulfur-containing compound (E), the above-mentioned problem regarding the adhesion of the plated object is almost or only slightly observed. Therefore, when a compound containing a nitrogen-containing aromatic heterocycle substituted with a mercapto group is used as the sulfur-containing compound (E), a plated object having good adhesion to a metal surface can be easily formed without ashing.

[0412] The ashing process is not particularly limited as long as it is a method that does not cause damage to the resist pattern that serves as a mold for forming a plated object to such an extent that a plated object of a desired shape cannot be formed. A preferred ashing method is a method using oxygen plasma. In order to ash a metal surface on a substrate using oxygen plasma, oxygen plasma is generated using a known oxygen plasma generator, and the oxygen plasma is irradiated onto the metal surface on the substrate.

[0413] The gas used to generate oxygen plasma can be mixed with various gases that have been used in plasma treatment together with oxygen, as long as the object of the present invention is not impaired. Examples of such gases include nitrogen gas, hydrogen gas, and CF4 gas. The conditions for ashing using oxygen plasma are not particularly limited as long as they do not impair the object of the present invention, but the treatment time is, for example, in the range of 10 seconds to 20 minutes, preferably in the range of 20 seconds to 18 minutes, and more preferably in the range of 30 seconds to 15 minutes. By setting the treatment time with oxygen plasma within the above range, it becomes easier to obtain the effect of improving the adhesion of the plated object without causing any change in the shape of the resist pattern.

[0414] The above-mentioned photosensitive composition makes it possible to form a highly precise resist pattern having a desired shape and a rectangular cross-sectional shape. This resist pattern can be used as a mold for forming a plating object, thereby enabling the realization of even higher density and precision of protruding electrodes, metal posts, etc. EXAMPLES

[0415] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0416] [Preparation Example 1] (Synthesis of mercapto compound T2) In Preparation Example 1, a mercapto compound T2 having the following structure was synthesized as the sulfur-containing compound (E). [ka]

[0417] Into a flask, 15.00 g of 7-oxanorborn-5-ene-2,3-dicarboxylic anhydride and 150.00 g of tetrahydrofuran were added and stirred. Next, 7.64 g of thioacetic acid (AcSH) was added to the flask and stirred at room temperature for 3.5 hours. After that, the reaction solution was concentrated to obtain 22.11 g of 5-acetylthio-7-oxanorbornane-2,3-dicarboxylic anhydride. 22.11 g of 5-acetylthio-7-oxanorbornane-2,3-dicarboxylic anhydride and 30.11 g of a 10% by mass aqueous sodium hydroxide solution were added to the flask, and the contents of the flask were stirred at room temperature for 2 hours. Next, 20% by mass hydrochloric acid (80.00 g) was added to the flask to make the reaction solution acidic. Then, extraction with 200 g of ethyl acetate was performed four times to obtain an extract containing mercapto compound T2. The extract was concentrated and the collected residue was dissolved by adding 25.11 g of tetrahydrofuran (THF). Heptane was added dropwise to the obtained THF solution to precipitate mercapto compound T2, and the precipitated mercapto compound T2 was collected by filtration. The mercapto compound T2 was extracted with 200 g of ethyl acetate four times. 1 The results of H-NMR measurements are shown below. 1 H-NMR (DMSO-d6): δ12.10(s,2H),4.72(d,1H),4.43(s,1H),3.10(t,1H),3.01(d,1H),2.85(d,1H),2.75(d,1H),2.10(t,1H),1.40(m,1H) [ka]

[0418] [Examples 1 to 5 and Comparative Examples 1 to 4] In Examples 1 to 5 and Comparative Examples 1 to 4, PAG1 represented by the following formula was used as the acid generator (A). [ka]

[0419] In Examples 1 to 5 and Comparative Examples 1 to 4, the following Resin A1 was used as a resin (Resin (B)) whose solubility in alkali increases under the action of an acid. The numbers in the brackets in each structural unit in the following structural formula indicate the content (mass%) of the structural unit in the resin. The mass average molecular weight Mw of Resin A1 is 42,000. [ka]

[0420] In Examples 1 to 5 and Comparative Examples 1 to 4, the following Resin B1 (polyhydroxystyrene resin) and Resin C (novolac resin (m-cresol homocondensate)) were used as the alkali-soluble resin (D). The numbers in the brackets at the bottom right of each structural unit in the following structural formulas indicate the content (mass%) of the structural unit in each resin. Resin B1 has a mass average molecular weight (Mw) of 2500 and a dispersity (Mw / Mn) of 2.4. Resin C has a mass average molecular weight (Mw) of 8000. [ka] [ka]

[0421] As the acid diffusion inhibitor (C), the following C1 to C7 were used. In C4, n1 and n2 are each 1. Also, C2 is a reaction product of benzeneamine, N-phenyl and 2,4,4-trimethylpentene. [ka]

[0422] C5: Triphenylamine C6: Tripentylamine C7: Aniline

[0423] As the sulfur-containing compound (E), the following sulfur-containing compounds T1 and T2 were used. [ka]

[0424] The photosensitive compositions of each Example and Comparative Example were obtained by dissolving the acid generator (A), resin (B), acid diffusion inhibitor (C), alkali-soluble resin (D), and sulfur-containing compound (E) of the type and mass part shown in Table 1, and 0.05 mass part of a surfactant (BYK310, manufactured by BYK-Chemie) in 3-methoxybutyl acetate (MA) so that the solid content concentration was 51 mass%. Note that the unit in Table 1 is parts by mass, and only the amount of the acid diffusion inhibitor (C) is shown in parts by mass relative to 100 mass parts of the resin (B).

[0425] The photosensitive composition thus obtained was evaluated for resolution, dimensional controllability, cross-sectional perpendicularity, and cross-sectional interface shape according to the following methods. The evaluation results are shown in Table 1.

[0426] [Resolution evaluation] A substrate was prepared in which a copper film of 200 nm thickness was provided on the surface of a Si substrate by sputtering, and the photosensitive compositions of the Examples and Comparative Examples were applied onto the copper layer of this substrate and dried on a hot plate at 145°C for 5 minutes to form a photosensitive layer (coating film of the photosensitive composition) with a thickness of 65 µm. Next, a 10 µm hole pattern mask and a Prisma GHI5452 projection exposure apparatus (Ultratech, NA = 0.16) were used to apply 500 mJ / cm 2 The pattern was exposed to ghi rays at an exposure dose of 100°C. The substrate was then placed on a hot plate and post-exposure baked (PEB) at 100°C for 3 minutes. After that, a 2.38% by weight aqueous solution of tetramethylammonium hydroxide (TMAH) (developer, NMD-3, manufactured by Tokyo Ohka Kogyo Co., Ltd.) was dropped onto the exposed photosensitive layer, and the layer was left to stand at 23°C for 60 seconds (paddle development). This operation was repeated five times in total. The surface of the resist pattern was then washed (rinsed) with running water for 60 seconds, and spin-dried to obtain a resist pattern. The obtained resist pattern (hole pattern) was observed with an optical microscope and a scanning electron microscope (SEM). When a 10 μm pattern was formed, it was rated as ◯, and when a 10 μm pattern was not formed, it was rated as ×.

[0427] [Evaluation of dimensional controllability] A resist pattern was obtained by carrying out the same operations as in [Evaluation of resolution], except that a mask with a 30 μm hole pattern was used as the mask. For the obtained resist patterns (hole patterns), a scanning electron microscope was used to measure the diameter (hole dimension) of the surface (bottom) of the resist pattern that contacted the substrate. If the hole dimension was within 30 μm ± 10%, it was rated as ◎, if it was outside the range of 30 μm ± 10% and within 30 μm ± 30%, it was rated as ○, if it was outside the range of 30 μm ± 30% and within 30 μm ± 50%, it was rated as △, and if it was outside the range of 30 μm ± 50%, it was rated as ×.

[0428] [Evaluation of the perpendicularity of the cross section (evaluation of the rectangularity of the cross section shape)] The cross-sectional shape of the resist pattern (hole pattern) obtained in [Evaluation of dimensional controllability] was observed with a scanning electron microscope, and the width Wb of the surface of the resist pattern that contacted the substrate (bottom), the pattern width Wm of the middle part of the resist pattern cross-section in the thickness direction, and the width Wt of the surface opposite the surface of the resist pattern that contacted the substrate (top) were measured. The standard deviations (σ) of Wb, Wm, and Wt were calculated, and values ​​less than 1 were evaluated as ◎, values ​​between 1 and 2 were evaluated as ○, values ​​between 2 and 3 were evaluated as △, and values ​​3 or more were evaluated as ×.

[0429] [Evaluation of cross-sectional interface shape (evaluation of rectangularity of substrate interface shape)] For the resist patterns obtained in [Evaluation of dimensional controllability], the interface between the substrate and the resist pattern was observed with a scanning electron microscope. If no footing was observed or if footing was observed but the foot length was less than 0.5 μm, it was rated as ◎, if the footing was 0.5 μm or more but less than 1 μm, it was rated as ○, if the footing was 1 μm or more but less than 2 μm, it was rated as △, if the footing was 2 μm or more, it was rated as ×, and if it was an indented shape, it was rated as XX.

[0430] [Table 1]

[0431] According to Examples 1 to 5, it can be seen that a photosensitive composition in which a compound represented by formula (C1) is blended as an acid diffusion inhibitor (C) into a chemically amplified positive photosensitive composition containing an acid generator (A) that generates an acid upon exposure to actinic rays or radiation, and a resin (B) whose solubility in alkali increases due to the action of an acid, can form a resist pattern with good cross-sectional perpendicularity, good interface shape, and good rectangularity, and also has high resolution and dimensional controllability.

[0432] On the other hand, according to Comparative Examples 1 to 4, when the photosensitive composition contains, instead of the compound represented by formula (C1), acid diffusion inhibitors C5 to C7 which are not compounds represented by formula (C1), the resolution, dimensional controllability, cross-sectional perpendicularity and interface shape are all poor.

Claims

1. The composition contains an acid generator (A) that generates an acid when irradiated with actinic rays or radiation, a resin (B) whose solubility in alkali increases under the action of an acid, and an acid diffusion inhibitor (C), The acid diffusion inhibitor (C) comprises a compound represented by the following formula (C1): 【Chemistry 1】 (In formula (C1), R １ｃ is an alkyl group or an aralkyl group, R ２ｃ is an alkyl group or an aralkyl group, R ３ｃ is a hydrogen atom, R ４ｃ is a single bond, n1 is an integer of 0 to 5, n2 is an integer of 0 to 5, n3 is 1, and n1 and n2 cannot be 0 at the same time.)

2. The R １ｃ The number of carbon atoms of the alkyl group or the aralkyl group represented by R is 6 or more and 10 or less, ２ｃ 2. The chemically amplified positive photosensitive composition according to claim 1, wherein the alkyl group or the aralkyl group has 6 or more and 10 or less carbon atoms.

3. 3. The chemically amplified positive photosensitive composition according to claim 1, wherein the content of the acid diffusion inhibitor (C) is from 0.01 parts by mass to 20 parts by mass based on 100 parts by mass of the resin (B).

4. The chemically amplified positive-type photosensitive composition according to any one of claims 1 to 3, further comprising an alkali-soluble resin (D).

5. 5. The chemically amplified positive-type photosensitive composition according to claim 4, wherein the alkali-soluble resin (D) comprises at least one resin selected from the group consisting of a novolak resin (D1), a polyhydroxystyrene resin (D2), and an acrylic resin (D3).

6. A photosensitive dry film comprising a base film and a photosensitive layer formed on a surface of the base film, the photosensitive layer being made of the chemically amplified positive-type photosensitive composition according to any one of claims 1 to 5.

7. A method for producing a photosensitive dry film, comprising applying the chemically amplified positive-type photosensitive composition according to any one of claims 1 to 5 onto a substrate film to form a photosensitive layer.

8. A lamination step of laminating a photosensitive layer made of the chemically amplified positive-type photosensitive composition according to any one of claims 1 to 5 on a substrate; an exposure step of position-selectively irradiating the photosensitive layer with actinic rays or radiation; and a developing step of developing the photosensitive layer after exposure.

9. An acid diffusion inhibitor to be blended in a chemically amplified positive-working photosensitive composition, the acid diffusion inhibitor comprising: an acid generator (A) that generates an acid when irradiated with actinic rays or radiation; and a resin (B) whose solubility in alkali increases under the action of an acid, An acid diffusion inhibitor comprising a compound represented by the following formula (C1): 【Chemistry 2】 (In formula (C1), R １ｃ is an alkyl group or an aralkyl group, R ２ｃ is an alkyl group or an aralkyl group, R ３ｃ is a hydrogen atom, R ４ｃ is a single bond, n1 is an integer of 0 to 5, n2 is an integer of 0 to 5, n3 is 1, and n1 and n2 cannot be 0 at the same time.)

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