JP2005029548A - Sulfonium compound, radiation-sensitive acid generator and radiation-sensitive resin composition comprising the sulfonium compound - Google Patents

Abstract

〔式中、Ｒ¹ は１価の（置換）芳香族炭化水素基、Ｒ² およびＲ³ は（シクロ）アルキル基、（シクロ）アルコキシル基、有機スルファニル基、有機スルホニル基等、ｐおよびｑは０〜６の整数、Ｘ^- は１価の有機酸アニオンまたはＯＨ^- を示す。〕 感放射線性酸発生剤は該スルホニウム化合物からなる。
感放射線性樹脂組成物は、該感放射線性酸発生剤以外に、ポジ型では酸解離性基含有樹脂を含有し、ネガ型ではアルカリ可溶性樹脂と架橋剤を含有する。
【選択図】 なしPROBLEM TO BE SOLVED: To provide a sulfonium compound suitable as a radiation sensitive acid generator for a chemically amplified resist capable of preventing problems such as standing wave effect, halation effect and swing curve even when used on a substrate with high radiation reflectivity, and the sulfonium compound And a radiation-sensitive resin composition containing the radiation-sensitive acid generator.
A sulfonium compound is represented by the following general formula (1).
[Chemical 1]

[Wherein R ¹ is a monovalent (substituted) aromatic hydrocarbon group, R ² and R ³ are (cyclo) alkyl groups, (cyclo) alkoxyl groups, organic sulfanyl groups, organic sulfonyl groups, etc., and p and q are An integer of 0 to 6, X ⁻ represents a monovalent organic acid anion or OH ⁻ . The radiation sensitive acid generator is composed of the sulfonium compound.
In addition to the radiation-sensitive acid generator, the radiation-sensitive resin composition contains an acid-dissociable group-containing resin in the positive type and an alkali-soluble resin and a crosslinking agent in the negative type.
[Selection figure] None

Description

The present invention relates to (super) deep ultraviolet rays, synchrotron radiation, and the like represented by KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), F ₂ excimer laser (wavelength 157 nm) or EUV (wavelength 13 nm, etc.) Radiation sensitivity useful for resists for semiconductor integrated circuit formation, which changes its solubility in alkali in response to various types of radiation such as charged particle beams such as X-rays and electron beams, and forms a fine pattern by alkali development. The present invention relates to a sulfonium compound suitable as a radiation-sensitive acid generator for a photosensitive resin composition, a radiation-sensitive acid generator comprising the sulfonium compound, and a radiation-sensitive resin composition containing the radiation-sensitive acid generator.

In recent years, with high integration of semiconductor integrated circuits represented by LSI, fine processing with a line width of 0.20 μm or less is required, and conventionally used g-line (wavelength 436 nm) and i-line (wavelength 365 nm). It is said that it is difficult to meet this requirement with a photolithography technique using an exposure light source. Therefore, as an alternative to these conventional techniques, as an exposure light source, far ultraviolet rays typified by KrF excimer laser, ArF excimer laser or F ₂ excimer laser, ultra far ultraviolet rays typified by EUV, X-rays, charged particle beams Photolithography using a high energy particle beam such as the above has been proposed.

On the other hand, for photolithography using a KrF excimer laser as an exposure light source, the conventionally used novolak resin-naphthoquinonediazide resist cannot be used due to its strong absorption in the far-ultraviolet region. Proposed many highly chemically amplified resists with high transparency to KrF excimer lasers, consisting of a resin component that undergoes a chemical reaction that changes the solubility of the developer in the presence of a catalyst and a radiation-sensitive acid generator that generates acid upon exposure. Has been.
Typical examples thereof include a resin component in which the phenolic hydroxyl group of polyhydroxystyrene is protected with an acid-dissociable protecting group such as acetal or t-butoxycarbonyl group, and a triarylsulfonium salt typified by a triphenylsulfonium salt. A chemically amplified resist for a KrF excimer laser using a radiation sensitive acid generator is widely known (for example, see Patent Document 1).

JP 59-45439 A

  However, when such a chemically amplified resist is used for a substrate having a high reflectivity against far ultraviolet rays such as a silicon substrate, an aluminum substrate, a chrome substrate for a photomask, the standing wave effect, the halation effect, the swing curve, etc. are problematic. It has become. Here, the “standing wave effect” means that the side wall of the pattern is wavy due to a periodic wave generated by the light incident on the resist being re-reflected on the substrate surface and the resist coating surface and causing light interference in the resist coating. A phenomenon that results in a shape, and the “halation effect” is a phenomenon in which reflected light is reflected obliquely on an uneven substrate, resulting in shape deterioration and dimensional variation. “Swing curve” is an exposure. This is a phenomenon in which the pattern dimension varies depending on the film thickness of the resist film due to the multiple interference effect of the emitted radiation.

  As a method for solving these problems, it is possible to control the radiation transmittance by adding a light absorber to the chemically amplified resist. As the light absorber used for this purpose, for example, a polycyclic aromatic compound such as anthracene having extremely strong absorption in the ultraviolet region is known. When this compound is used as a light absorber, pre-baking (PB ) Or post-exposure baking (PEB), part of the color sublimates, resulting in problems that a desired effect cannot be obtained and peripheral devices are contaminated. On the other hand, a method of controlling the radiation transmittance by increasing the addition amount of the radiation-sensitive acid generator in place of the light absorber is known, but in this case, the sensitivity of a conventional triphenylsulfonium salt or the like is known. In the case of a radioactive acid generator, it is necessary to increase the amount of the radiation-sensitive acid generator in order to lower the radiation transmittance to a desired level. With this, the pattern shape becomes an overcut shape, resolution, etc. There was a problem that the various performances deteriorated.

  The object of the present invention is to prevent problems such as standing wave effect, halation effect, swing curve, etc. even when used on a substrate with high radiation reflectivity, excellent pattern shape, and excellent resolution, storage stability, etc. A sulfonium compound suitable as a radiation sensitive acid generator for chemically amplified resists, a radiation sensitive acid generator comprising the sulfonium compound, and positive and negative radiation sensitive resins containing the radiation sensitive acid generator It is to provide a composition.

  As a result of detailed investigations on various compounds having an absorption wavelength in the far ultraviolet region, the present inventors have found that a di (β-naphthyl) arylsulfonium compound in which a sulfur atom is bonded to the β-position of naphthalene has an absorption maximum near a wavelength of 248 nm. And has a photobleaching property by KrF excimer laser exposure. Therefore, when used as a radiation-sensitive acid generator, the inventors have found that the above problems can be solved and the present invention is made. It came to.

According to the present invention, the problem is firstly
A sulfonium compound represented by the following general formula (1) (hereinafter referred to as “sulfonium compound (1)”),
Achieved by:

[In the general formula (1), R ¹ represents a substituted or unsubstituted monovalent aromatic hydrocarbon group having 6 to 20 carbon atoms, and R ² and R ³ are each independently a straight chain having 1 to 14 carbon atoms. A linear or branched alkyl group, a monovalent alicyclic hydrocarbon group having 3 to 14 carbon atoms, a linear or branched alkoxyl group having 1 to 14 carbon atoms, an —OR ⁴ group (provided that R ⁴ Represents a monovalent hydrocarbon group having 3 to 14 carbon atoms having an alicyclic ring.), A linear or branched alkylsulfanyl group having 1 to 14 carbon atoms, or 3 carbon atoms having an alicyclic ring. -14 organic sulfanyl group, a C1-C14 linear or branched alkylsulfonyl group, or a C3-C14 organic sulfonyl group having an alicyclic ring, p and q are each 0 to 6 is an integer of, X ^- is a monovalent organic acid anion having 1 to 20 carbon atoms The other is OH ^- show the. ]

According to the present invention, the above-mentioned problem is secondly a radiation-sensitive acid generator (hereinafter referred to as “acid generator (1)”) comprising a sulfonium compound (1).
Achieved by:

According to the present invention, the above-mentioned problems are thirdly (A) a radiation-sensitive acid generator containing the acid generator (1) as an essential component, and (B) an alkali-insoluble or hardly soluble resin having an acid-dissociable group. A positive radiation-sensitive composition comprising a resin that becomes alkali-soluble when the acid-dissociable group is dissociated,
Achieved by:

According to the present invention, the above-mentioned problem is fourthly (A) a radiation-sensitive acid generator having an acid generator (1) as an essential component, (C) in the presence of an acid and (D) a cross-linking agent that is cross-linked with an alkali. A negative-type radiation-sensitive resin composition comprising an alkali-soluble resin that becomes hardly soluble or insoluble, and (D) a crosslinking agent;
Achieved by:

Hereinafter, the present invention will be described in detail.
Sulfonium compound (1)
In the general formula (1), examples of the substituted or unsubstituted monovalent aromatic hydrocarbon group having 6 to 20 carbon atoms of R ¹ include a phenyl group; naphthalene, anthracene, phenanthrene, pyrene, triphenylene, tetracene, and indene. , Groups derived from polycyclic aromatic hydrocarbons such as biphenylene and fluorene; these groups are hydroxyl groups, linear or branched alkyl groups having 1 to 14 carbon atoms, and monovalent fats having 3 to 14 carbon atoms. A cyclic hydrocarbon group, a linear or branched alkoxyl group having 1 to 14 carbon atoms, an —OR ⁴ group (where R ⁴ is a monovalent hydrocarbon group having 3 to 14 carbon atoms having an alicyclic ring) A linear or branched alkylsulfanyl group having 1 to 14 carbon atoms, an organic sulfanyl group having 3 to 14 carbon atoms having an alicyclic ring, or a linear or branched group having 1 to 14 carbon atoms. It can be mentioned alkylsulfonyl group or substituted group of one or more types of organic sulfonyl group having 3 to 14 carbon atoms having an alicyclic ring or the like.

Among the substituents in the monovalent aromatic hydrocarbon group having 6 to 20 carbon atoms substituted for R ¹ , examples of the linear or branched alkyl group having 1 to 14 carbon atoms include a methyl group and an ethyl group. N-propyl group, i-propyl group, n-butyl group, 2-methylpropyl group, 1-methylpropyl group, t-butyl group, n-pentyl group, neopentyl group, n-hexyl group, n-heptyl group N-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, t-dodecyl group, n-tridecyl group, n-tetradecyl group and the like.

  Examples of the monovalent alicyclic hydrocarbon group having 3 to 14 carbon atoms include cycloalkyl groups such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group; norbornane, bicyclo [2.2.2]. A group consisting of an alicyclic ring derived from a bridged alicyclic hydrocarbon such as octane, tricyclodecane, tetracyclododecane, adamantane; a group consisting of these cycloalkyl group or alicyclic ring is a methylene group, Examples thereof include a group bonded to a linear or branched alkylene group having 1 to 8 carbon atoms such as an ethylene group and a propylene group.

  Examples of the linear or branched alkoxyl group having 1 to 14 carbon atoms include methoxy group, ethoxy group, n-propoxy group, i-propoxy group, n-butoxy group, 2-methylpropoxy group, 1 -Methylpropoxy group, t-butoxy group, n-pentyloxy group, n-hexyloxy group, n-heptyloxy group, n-octyloxy group, n-nonyloxy group, n-decyloxy group, n-undecyloxy group N-dodecyloxy group, t-dodecyloxy group, n-tridecyloxy group, n-tetradecyloxy group and the like.

In addition, R ⁴ in the —OR ⁴ group is, for example, a cycloalkyl group such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group; norbornane, tricyclodecane, bicyclo [2.2.2] octane, tetracyclo Groups composed of alicyclic rings derived from bridged alicyclic hydrocarbons such as dodecane and adamantane; these cycloalkyl groups or groups composed of alicyclic rings are methylene groups, ethylene groups, propylene groups, etc. Examples thereof include a group bonded to a linear or branched alkylene group having 1 to 8 carbon atoms.

  Examples of the linear or branched alkylsulfanyl group having 1 to 14 carbon atoms include a methylsulfanyl group, an ethylsulfanyl group, an n-propylsulfanyl group, an i-propylsulfanyl group, an n-butylsulfanyl group, and 2 -Methylpropylsulfanyl group, 1-methylpropylsulfanyl group, t-butylsulfanyl group, n-pentylsulfanyl group, n-hexylsulfanyl group, n-heptylsulfanyl group, n-octylsulfanyl group, n-nonylsulfanyl group, n Examples include -decylsulfanyl group, n-unenylsulfanyl group, n-dodecylsulfanyl group, n-tridecylsulfanyl group, n-tetradecylsulfanyl group and the like.

Examples of the organic sulfanyl group having an alicyclic ring having 3 to 14 carbon atoms include cycloalkylsulfanyl groups such as a cyclopropylsulfanyl group, a cyclobutylsulfanyl group, a cyclopentylsulfanyl group, and a cyclohexylsulfanyl group; (bicyclo [2 2.1] heptan-2-yl) sulfanyl group, (bicyclo [2.2.2] octan-2-yl) sulfanyl group, (tetracyclo [4.2.0.1 ^2.5 .1 ^7.10 ] dodecane-3 An organic sulfanyl group in which an alicyclic ring derived from a bridged alicyclic hydrocarbon such as a -yl) sulfanyl group or (adamantan-1-yl) sulfanyl group is directly connected to a sulfur atom; a cycloalkyl group (for example, cyclopropyl Group, cyclobutyl group, cyclopentyl group, cyclohexyl group, etc.) or bridged alicyclic hydrocarbon A group comprising an alicyclic ring derived from a group (for example, norbornane, bicyclo [2.2.2] octane, tricyclodecane, tetracyclododecane, adamantane, etc.) is a methylene group, an ethylene group, a propylene group, or the like. Examples thereof include an organic sulfanyl group bonded to a sulfur atom via a linear or branched alkylene group having 1 to 8 carbon atoms.

Examples of the linear or branched alkylsulfonyl group having 1 to 14 carbon atoms include methanesulfonyl group, ethanesulfonyl group, propane-1-sulfonyl group, propane-2-sulfonyl group, and butane-1-sulfonyl. Group, 2-methylpropane-1-sulfonyl group, 1-methylpropane-1-sulfonyl group, 2-methylpropane-2-sulfonyl group, pentane-1-sulfonyl group, hexane-1-sulfonyl group, heptane-1- Sulfonyl group, octane-1-sulfonyl group, nonane-1-sulfonyl group, decane-1-sulfonyl group, undecane-1-sulfonyl group, dodecane-1-sulfonyl group, tridecane-1-sulfonyl group, tetradecane-1-sulfonyl In addition, an organic group having 3 to 14 carbon atoms having an alicyclic ring can be used. Examples of the sulfonyl group include cycloalkanesulfonyl groups such as cyclopropanesulfonyl group, cyclobutanesulfonyl group, cyclopentanesulfonyl group, cyclohexanesulfonyl group; bicyclo [2.2.1] heptane-2-sulfonyl group, bicyclo [2. 2.2] octane-2-sulfonyl group, tetracyclo [4.2.0.1 ^2.5 . 1 ^7.10 ] an organic sulfonyl group in which an alicyclic ring derived from a bridged alicyclic hydrocarbon such as a dodecane-3-sulfonyl group or an adamantane-1-sulfonyl group is directly connected to a sulfur atom; a cycloalkyl group (for example, cyclo Derived from propyl, cyclobutyl, cyclopentyl, cyclohexyl, etc.) or bridged alicyclic hydrocarbons (eg, norbornane, bicyclo [2.2.2] octane, tricyclodecane, tetracyclododecane, adamantane, etc.) An organic sulfonyl group bonded to a sulfur atom via a linear or branched alkylene group having 1 to 8 carbon atoms such as a methylene group, an ethylene group or a propylene group. be able to.

R ¹ in the general formula (1) is preferably a group represented by the following general formula (2), more preferably a group represented by the following general formula (3).

[In the general formula (2), R ⁵ represents a linear or branched alkyl group having 1 to 14 carbon atoms, a monovalent alicyclic hydrocarbon group having 3 to 14 carbon atoms, and a straight chain having 1 to 14 carbon atoms. A linear or branched alkoxyl group, —OR ⁴ group (where R ⁴ represents a monovalent hydrocarbon group having 3 to 14 carbon atoms having an alicyclic ring), linear chain having 1 to 14 carbon atoms Or branched alkylsulfanyl group, organic sulfanyl group having 3 to 14 carbon atoms having an alicyclic ring, linear or branched alkylsulfonyl group having 1 to 14 carbon atoms, or carbon having an alicyclic ring The organic sulfonyl group of number 3-14 is shown, r is an integer of 0-6. ]

[In General Formula (3), R ⁵ represents a linear or branched alkyl group having 1 to 14 carbon atoms, a monovalent alicyclic hydrocarbon group having 3 to 14 carbon atoms, and a straight chain having 1 to 14 carbon atoms. A linear or branched alkoxyl group, —OR ⁴ group (where R ⁴ represents a monovalent hydrocarbon group having 3 to 14 carbon atoms having an alicyclic ring), linear chain having 1 to 14 carbon atoms Or branched alkylsulfanyl group, organic sulfanyl group having 3 to 14 carbon atoms having an alicyclic ring, linear or branched alkylsulfonyl group having 1 to 14 carbon atoms, or carbon having an alicyclic ring The organic sulfonyl group of number 3-14 is shown, r is an integer of 0-6. ]

In General Formula (2) and General Formula (3), R ⁵ linear or branched alkyl group having 1 to 14 carbon atoms, monovalent alicyclic hydrocarbon group having 3 to 14 carbon atoms, carbon number 1-14 linear or branched alkoxyl group, —OR ⁴ group, C 1-14 linear or branched alkylsulfanyl group, C 3-14 organic sulfanyl having an alicyclic ring Group, a linear or branched alkylsulfonyl group having 1 to 14 carbon atoms, and an organic sulfonyl group having 3 to 14 carbon atoms having an alicyclic ring, for example, substitution of R ¹ in the general formula (1) The same groups as the corresponding groups exemplified for the substituent in the monovalent aromatic hydrocarbon group having 6 to 20 carbon atoms can be exemplified, and a plurality of R ⁵ may be the same or different from each other.

In general formula (2) and general formula (3), as R < ⁵ >, n-butoxy group, n-pentyloxy group, n-hexyloxy group, n-heptyloxy group, n-octyloxy group, cyclopentyloxy group Cyclohexyloxy group, (bicyclo [2.2.1] heptan-2-yl) oxy group, cyclopentylmethoxy group, cyclohexylmethoxy group, (bicyclo [2.2.1] heptan-2-yl) methoxy group, n -Butylsulfanyl group, n-pentylsulfanyl group, n-hexylsulfanyl group, n-heptylsulfanyl group, n-octylsulfanyl group, cyclopentylsulfanyl group, cyclohexylsulfanyl group, (bicyclo [2.2.1] heptane-2- Yl) sulfanyl group (bicyclo [2.2.1] octan-2-yl) Methylsulfanyl group, n-butanesulfonyl group, n-pentanesulfonyl group, n-hexanesulfonyl group, n-heptanesulfonyl group, n-octanesulfonyl group, bicyclo [2.2.1] heptane-2-sulfonyl group, Bicyclo [2.2.1] heptan-2-yl) methanesulfonyl group and the like are preferable.
Further, when the general formulas (2) and in (3) R ⁵ is present one or more, it is preferred that one each is bonded to the 6-position of the naphthalene ring.
Moreover, in General formula (2) and General formula (3), as r, 0-1 are preferable, Most preferably, it is 0.

In the general formula (1), a linear or branched alkyl group having 1 to 14 carbon atoms of R ² and R ^3, a monovalent alicyclic hydrocarbon group having 3 to 14 carbon atoms, and 1 to 14 carbon atoms A linear or branched alkoxyl group, —OR ⁴ group, a linear or branched alkylsulfanyl group having 1 to 14 carbon atoms, an organic sulfanyl group having 3 to 14 carbon atoms having an alicyclic ring, carbon Examples of the linear or branched alkylsulfonyl group having 1 to 14 and the organic sulfonyl group having 3 to 14 carbon atoms having an alicyclic ring include, for example, the number of carbon atoms substituted for R ¹ in the general formula (1) The same groups as the corresponding groups exemplified for the substituent in the monovalent aromatic hydrocarbon group of 6 to 20 can be mentioned, and a plurality of R ² and a plurality of R ³ are the same or different from each other. May be.

In the general formula (1), as R ² and R ³ , n-butoxy group, n-pentyloxy group, n-hexyloxy group, n-heptyloxy group, n-octyloxy group, cyclopentyloxy group, cyclohexyloxy Group, (bicyclo [2.2.1] heptan-2-yl) oxy group, cyclopentylmethoxy group, cyclohexylmethoxy group, (bicyclo [2.2.1] heptan-2-yl) methoxy group, n-butylsulfanyl Group, n-pentylsulfanyl group, n-hexylsulfanyl group, n-heptylsulfanyl group, n-octylsulfanyl group, cyclopentylsulfanyl group, cyclohexylsulfanyl group, (bicyclo [2.2.1] heptan-2-yl) sulfanyl Group (bicyclo [2.2.1] octan-2-yl) methyls Fanyl group, n-butanesulfonyl group, n-pentanesulfonyl group, n-hexanesulfonyl group, n-heptanesulfonyl group, n-octanesulfonyl group, bicyclo [2.2.1] heptane-2-sulfonyl group, (bicyclo [2.2.1] Heptan-2-yl) methanesulfonyl group and the like are preferable.
Further, when one or more R ² or one or more R ³ are present in the general formula (1), it is preferable that each one is bonded to the 6-position of the naphthalene ring.
In the general formula (1), p and q are each preferably 0 to 1, particularly preferably 0.

In the general formula (1), examples of the organic acid anion having 1 to 20 carbon atoms of X ⁻ include a sulfonate anion, a carboxylate anion, and a phenolate anion.

Examples of the sulfonate anion of X ⁻ include linear or branched methanesulfonate anion, ethanesulfonate anion, n-propanesulfonate anion, n-butanesulfonate anion, n-hexanesulfonate anion and the like. Alkyl sulfonate anions;
Sulfonate anions having an alicyclic ring such as cyclohexane sulfonate anion, d-camphor-10-sulfonate anion;
Benzenesulfonate anion, p-toluenesulfonate anion, 4-methoxybenzenesulfonate anion, 4-n-octylbenzenesulfonate anion, 1-naphthalenesulfonate anion, 2-naphthalenesulfonate anion, pyrene-2-sulfonate Aromatic sulfonate anions such as anions, 9-anthracenesulfonate anions, 9,10-dimethoxyanthracene-2-sulfonate anions;
2-fluorobenzenesulfonate anion, 3-fluorobenzenesulfonate, 4-fluorobenzenesulfonate anion, 2,4-difluorobenzenesulfonate anion, 3,5-difluorobenzenesulfonate anion, 3,4,5-tri Fluorine-substituted benzenesulfonate anions such as fluorobenzenesulfonate anion and perfluorobenzenesulfonate anion;

2-trifluoromethylbenzenesulfonate anion, 3-trifluoromethylbenzenesulfonate anion, 4-trifluoromethylbenzenesulfonate anion, 2,4-bis (trifluoromethyl) benzenesulfonate anion, 3,5-bis An aromatic sulfonate anion having an electron-withdrawing substituent such as (trifluoromethyl) benzenesulfonate anion;
1,1-difluoroethanesulfonic acid anion, 1,1-difluoro-n-propanesulfonic acid anion, 1,1-difluoro-n-butanesulfonic acid anion, 1,1-difluoro-n-octanesulfonic acid anion, 2- 1,1-difluoroalkanesulfonic acid anions such as cyclohexyl-1,1-difluoroethanesulfonic acid anion, 2- (bicyclo [2.2.1] heptan-2-yl) -1,1-difluoroethanesulfonic acid anion, and the like Derivatives;
Trifluoromethanesulfonate anion, sulfonate anion represented by the following formula (4) (hereinafter referred to as “sulfonate anion (4)”)
Etc.

〔一般式（４）において、Ｒ⁶ は置換もしくは無置換の炭素数１〜１４の直鎖状もしくは分岐状のアルキル基または脂環式環を有する置換もしくは無置換の炭素数３〜１４の１価の炭化水素基を示す。〕

[In General Formula (4), R ⁶ is a substituted or unsubstituted 1 to 14 carbon atom having a substituted or unsubstituted C 1-14 linear or branched alkyl group or an alicyclic ring. Valent hydrocarbon group. ]

In the general formula (4), examples of the unsubstituted linear or branched alkyl group having 1 to 14 carbon atoms of R ⁶ include, for example, a methyl group, an ethyl group, an n-propyl group, an i-propyl group, n -Butyl group, 2-methylpropyl group, 1-methylpropyl group, t-butyl group, n-pentyl group, neopentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n -A decyl group, n-undecyl group, n-dodecyl group, t-dodecyl group, n-tridecyl group, n-tetradecyl group etc. can be mentioned.

Examples of the unsubstituted monovalent hydrocarbon group having 3 to 14 carbon atoms having an alicyclic ring of R ⁶ include, for example, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cycloalkyl group, a cycloalkyl group; norbornane, Groups consisting of alicyclic rings derived from bridged alicyclic hydrocarbons such as bicyclo [2.2.2] octane, tricyclodecane, tetracyclododecane, adamantane; these cycloalkyl groups or alicyclic rings And a group in which a group consisting of is bonded to a linear or branched alkylene group having 1 to 8 carbon atoms such as a methylene group, an ethylene group, or a propylene group.

In addition, examples of the substituent for the alkyl group having 1 to 14 carbon atoms and the monovalent hydrocarbon group having 3 to 14 carbon atoms having the alicyclic ring represented by R ⁶ include a hydroxyl group, a carboxyl group, and an oxo group. (═O), a cyano group, a halogen atom (eg, fluorine atom, chlorine atom, etc.), a C 1-8 linear or branched alkoxyl group (eg, methoxy group, ethoxy group, n-propoxy group, i -Propoxy group, n-butoxy group, 2-methylpropoxy group, 1-methylpropoxy group, t-butoxy group, etc.), linear or branched alkoxyalkoxyl group having 2 to 8 carbon atoms (for example, methoxymethoxy group) , An ethoxymethoxy group, a t-butoxymethoxy group, etc.), a linear or branched alkylcarbonyloxy group having 2 to 8 carbon atoms (for example, methylcarbonyl Oxy group, ethylcarbonyloxy group, t-butylcarbonyloxy group, etc.), linear or branched alkoxycarbonyl group having 2 to 8 carbon atoms (for example, methoxycarbonyl group, ethoxycarbonyl group, t-butoxycarbonyl group, etc.) ) And the like, or one or more.

In the general formula (4), examples of R ⁶ include a pentafluoroethyl group, a nonafluoro-n-butyl group, a perfluoro-n-hexyl group, a bicyclo [2.2.1] heptan-2-yl group, and the like. preferable.

In the general formula (1), examples of the carboxylate anion of X ⁻ include formate anion, acetate anion, propionate anion, butyrate anion, isobutyrate anion, valerate anion, isovalerate anion, pivalate anion, hexanoate. Monovalent linear or branched monovalent aliphatic carboxylate anions such as anion, heptanoic acid anion, octanoic acid anion, nonanoic acid anion, decanoic acid anion, lauric acid anion, myristic acid anion;
Monovalent carboxylate anion having an alicyclic ring such as cyclohexanecarboxylate anion, cycloheptanecarboxylate anion, bicyclo [2.2.1] heptane-2-carboxylate anion;
Linear or branched divalent aliphatic carboxylate anions such as oxalate anion, malonate anion, succinate anion, glutarate anion, pimelate anion, suberate anion, azelate anion, sebacate anion;
Examples thereof include benzoic acid anions, phthalic acid anions, isophthalic acid anions, terephthalic acid anions, naphthoic acid anions, toluic acid anions, and aromatic carboxylic acid anions such as anthracene-9-carboxylic acid anions.

In general formula (1), X ^- as phenolate anion of, for example,
Phenol, 1-naphthol, 2-naphthol, 9-anthrol, 2-phenanthrol, 2-nitrophenol, 3-nitrophenol, 4-nitrophenol, 2,4-dinitrophenol, picric acid, 2-fluorophenol, 3-fluorophenol, 4-fluorophenol, 2,4-difluorophenol, 2,4,6-trifluorophenol, 2-trifluoromethylphenol, 3-trifluoromethylphenol, 4-trifluoromethylphenol, 2, 4-bis (trifluoromethyl) phenol, 2,4,6-tris (trifluoromethyl) phenol, 2-hydroxyacetophenone, 3-hydroxyacetophenone, 4-hydroxyacetophenone,

o-cresol, m-cresol, p-cresol, 2-ethylphenol, 3-ethylphenol, 4-ethylphenol, 2-n-propylphenol, 3-n-propylphenol, 4-n-propylphenol, 2- i-propylphenol, 3-i-propylphenol, 4-i-propylphenol, 2-n-butylphenol, 3-n-butylphenol, 4-n-butylphenol, 2- (1-methylpropyl) phenol, 3- ( 1-methylpropyl) phenol, 4- (1-methylpropyl) phenol, 2-t-butylphenol, 3-t-butylphenol, 4-t-butylphenol,

2,6-diethylphenol, 2,6-di-n-propylphenol, 2,6-di-i-propylphenol, 2,6-di-n-butylphenol, 2,6-di (1-methylpropyl) Phenol, 2,6-di-t-butylphenol, 2,4,6-triethylphenol, 2,4,6-tri-n-propylphenol, 2,4,6-tri-i-propylphenol, 2,4 , 6-tri-n-butylphenol, 2,4,6-tri (1-methylpropyl) phenol, 2,4,6-tri-t-butylphenol and the like.

In the general formula (1), X ⁻ is an organic acid anion having 2 to 20 carbon atoms, more specifically, a sulfonic acid anion having 2 to 20 carbon atoms, a carboxylic acid anion having 2 to 20 carbon atoms, or the number of carbon atoms. A 6-20 phenolate anion is preferred, and a more preferred sulfonate anion having 2-20 carbon atoms is d-camphor-10-sulfonate anion, sulfonate anion (4), etc., particularly preferably d-camphor. -10-sulfonic acid anion, 2- (bicyclo [2.2.1] heptan-2-yl) -1,1,2,2-tetrafluoroethanesulfonic acid anion, and more preferably 2-20 carbon atoms Carboxylic acid anions include pivalic acid anion, cyclohexane carboxylic acid anion, bicyclo [2.2.1] heptane-2-carboxylic acid anion, benzoic acid More preferred examples of the phenolate anion having 6 to 20 carbon atoms such as anion include picric acid, 2,4,6-trifluorophenol, 2,6-di-i-propylphenol, 2,6-di-t- Anions derived from butylphenol, 2,4,6-tri-t-butylphenol and the like.

As a specific example of a preferable sulfonium compound (1) in which X ⁻ is a sulfonate anion having 2 to 20 carbon atoms,
Bis (6-n-butoxynaphthalen-2-yl) -1-naphthylsulfonium d-camphor-10-sulfonate, bis (6-cyclohexyloxynaphthalen-2-yl) -1-naphthylsulfonium d-camphor-10-sulfonate Bis [6- (bicyclo [2.2.1] heptan-2-yloxy) naphthalen-2-yl] -1-naphthylsulfonium d-camphor-10-sulfonate,
Bis (6-cyclohexylmethoxynaphthalen-2-yl) -1-naphthylsulfonium d-camphor-10-sulfonate, bis [6-{(bicyclo [2.2.1] heptan-2-yl) methoxy} naphthalene-2 -Yl] -1-naphthylsulfonium d-car-10-sulfonate,

Bis (6-n-butylsulfanylnaphthalen-2-yl) -1-naphthylsulfonium d-camphor-10-sulfonate, bis (6-cyclohexylsulfanylnaphthalen-2-yl) -1-naphthylsulfonium d-camphor-10- Sulfonate, bis [6- (bicyclo [2.2.1] heptan-2-ylsulfanyl) naphthalen-2-yl] -1-naphthylsulfonium d-camphor-10-sulfonate,
Bis (6-cyclohexylmethylsulfanylnaphthalen-2-yl) -1-naphthylsulfonium d-camphor-10-sulfonate, bis [6-{(bicyclo2.2.1] heptan-2-yl) methylsulfanyl} naphthalene- 2-yl] -1-naphthylsulfonium d-camphor-10-sulfonate,

Bis (6-n-butanesulfonylnaphthalen-2-yl) -1-naphthylsulfonium d-camphor-10-sulfonate, bis (6-cyclohexanesulfonylnaphthalen-2-yl) -1-naphthylsulfonium d-camphor-10- Sulfonate, bis [6- (bicyclo [2.2.1] heptane-2-sulfonyl) naphthalen-2-yl] -1-naphthylsulfonium d-camphor-10-sulfonate,
Bis (6-cyclohexylmethanesulfonylnaphthalen-2-yl) -1-naphthylsulfonium d-camphor-10-sulfonate, bis [6-{(bicyclo [2.2.1] heptan-2-yl) methanesulfonyl} naphthalene -2-yl] -1-naphthylsulfonium d-camphor-10-sulfonate,

Bis (6-n-butoxynaphthalen-2-yl) -2-naphthylsulfonium d-camphor-10-sulfonate, bis (6-cyclohexyloxynaphthalen-2-yl) -2-naphthylsulfonium d-camphor-10-sulfonate Bis [6- (bicyclo [2.2.1] heptan-2-yloxy) naphthalen-2-yl] -2-naphthylsulfonium d-camphor-10-sulfonate,
Bis (6-cyclohexylmethoxynaphthalen-2-yl) -2-naphthylsulfonium d-camphor-10-sulfonate, bis [6- (bicyclo [2.2.1] heptan-2-ylmethoxy) naphthalen-2-yl] 2-naphthylsulfonium d-camphor-10-sulfonate,

Bis (6-n-butylsulfanylnaphthalen-2-yl) -2-naphthylsulfonium d-camphor-10-sulfonate, bis (6-cyclohexylsulfanylnaphthalen-2-yl) -2-naphthylsulfonium d-camphor-10- Sulfonate, bis [6- (bicyclo [2.2.1] heptan-2-ylsulfanyl) naphthalen-2-yl] -2-naphthylsulfonium d-camphor-10-sulfonate,
Bis (6-cyclohexylmethylsulfanylnaphthalen-2-yl) -2-naphthylsulfonium d-camphor-10-sulfonate, bis [6-{(bicyclo [2.2.1] heptan-2-yl) methylsulfanyl} naphthalene -2-yl] -2-naphthylsulfonium d-camphor-10-sulfonate,

Bis (6-n-butanesulfonylnaphthalen-2-yl) -2-naphthylsulfonium d-camphor-10-sulfonate, bis (6-cyclohexanesulfonylnaphthalen-2-yl) -2-naphthylsulfonium d-camphor-10- Sulfonate, bis [6- (bicyclo [2.2.1] heptane-2-sulfonyl) naphthalen-2-yl] -2-naphthylsulfonium d-camphor-10-sulfonate,
Bis (6-cyclohexylmethanesulfonylnaphthalen-2-yl) -2-naphthylsulfonium d-camphor-10-sulfonate, bis [6-{(bicyclo [2.2.1] heptan-2-yl) methanesulfonyl} naphthalene -2-yl] -2-naphthylsulfonium d-camphor-10-sulfonate,

Di-2-naphthyl (6-n-butoxynaphthalen-2-yl) sulfonium d-camphor-10-sulfonate, di-2-naphthyl (6-cyclohexyloxynaphthalen-2-yl) sulfonium d-camphor-10-sulfonate Di-2-naphthyl [6- (bicyclo [2.2.1] heptan-2-yloxy) naphthalen-2-yl] sulfonium d-camphor-10-sulfonate,
Di-2-naphthyl (6-cyclohexylmethoxynaphthalen-2-yl) sulfonium d-camphor-10-sulfonate, di-2-naphthyl [6- (bicyclo [2.2.1] heptan-2-ylmethoxy) naphthalene- 2-yl] sulfonium d-camphor-10-sulfonate,

Di-2-naphthyl (6-n-butylsulfanylnaphthalen-2-yl) sulfonium d-camphor-10-sulfonate, di-2-naphthyl (6-cyclohexylsulfanylnaphthalen-2-yl) sulfonium d-camphor-10- Sulfonate, di-2-naphthyl [6- (bicyclo [2.2.1] heptan-2-ylsulfanyl) naphthalen-2-yl] sulfonium d-camphor-10-sulfonate,
Di-2-naphthyl (6-cyclohexylmethylsulfanylnaphthalen-2-yl) sulfonium d-camphor-10-sulfonate, di-2-naphthyl [6-{(bicyclo [2.2.1] heptan-2-yl) Methylsulfanyl} naphthalen-2-yl] sulfonium d-camphor-10-sulfonate,

Di-2-naphthyl (6-n-butanesulfonylnaphthalen-2-yl) sulfonium d-camphor-10-sulfonate, di-2-naphthyl (6-cyclohexanesulfonylnaphthalen-2-yl) sulfonium d-camphor-10- Sulfonate, di-2-naphthyl [6- (bicyclo [2.2.1] heptane-2-sulfonyl) naphthalen-2-yl] sulfonium d-camphor-10-sulfonate,
Di-2-naphthyl (6-cyclohexylmethanesulfonylnaphthalen-2-yl) sulfonium d-camphor-10-sulfonate, di-2-naphthyl [6-{(bicyclo [2.2.1] heptan-2-yl) Methanesulfonyl} naphthalen-2-yl] sulfonium d-camphor-10-sulfonate,

Tris (6-n-butoxynaphthalen-2-yl) sulfonium d-camphor-10-sulfonate, tris (6-cyclohexyloxynaphthalen-2-yl) sulfonium d-camphor-10-sulfonate, tris [6- (bicyclo [ 2.2.1] heptan-2-yloxy) naphthalen-2-yl] sulfonium d-camphor-10-sulfonate,
Tris (6-cyclohexylmethoxynaphthalen-2-yl) sulfonium d-camphor-10-sulfonate, tris [6- (bicyclo [2.2.1] heptan-2-ylmethoxy) naphthalen-2-yl] sulfonium d-camphor -10-sulfonate,

Tris (6-n-butylsulfanylnaphthalen-2-yl) sulfonium d-camphor-10-sulfonate, tris (6-cyclohexylsulfanylnaphthalen-2-yl) sulfonium d-camphor-10-sulfonate, tris [6- (bicyclo [2.2.1] heptan-2-ylsulfanyl) naphthalen-2-yl] sulfonium d-camphor-10-sulfonate,
Tris (6-cyclohexylmethylsulfanylnaphthalen-2-yl) sulfonium d-camphor-10-sulfonate sulfonate, tris [6-{(bicyclo [2.2.1] heptan-2-yl) methylsulfanyl} naphthalene-2- Yl] sulfonium d-camphor-10-sulfonate,

Tris (6-n-butanesulfonylnaphthalen-2-yl) sulfonium d-camphor-10-sulfonate, tris (6-cyclohexanesulfonylnaphthalen-2-yl) sulfonium d-camphor-10-sulfonate, tris [6- (bicyclo [2.2.1] heptane-2-sulfonyl) naphthalen-2-yl] sulfonium d-camphor-10-sulfonate,
Tris (6-cyclohexylmethanesulfonylnaphthalen-2-yl) sulfonium d-camphor-10-sulfonate, tris [6-{(bicyclo [2.2.1] heptan-2-yl) methanesulfonyl} naphthalen-2-yl Sulfonium d-camphor-10-sulfonate,

Sulfonium d-camphor-10-sulfonates such as tri-2-naphthylsulfonium d-camphor-10-sulfonate, di-2-naphthyl (1-naphthyl) sulfonium d-camphor-10-sulfonate,
The d-camphor-10-sulfonic acid anion in each compound is trifluoromethanesulfonic acid anion, nonafluoro-n-butanesulfonic acid anion or 2- (bicyclo [2.2.1] heptan-2-yl) -1 , 1,2,2, -tetrafluoroethanesulfonic acid anion, and the like.

As specific examples of the preferred sulfonium compound (1) other than the above, the sulfonate anion having 2 to 20 carbon atoms of X ^{− in} the preferred sulfonium compound (1) may be pivaloyl anion or 2,6-di-t-. Examples thereof include compounds substituted with butyl phenolate anions.

The sulfonium compound (1) is an active radiation such as a KrF excimer laser (wavelength) particularly in a radiation sensitive resin composition useful as a chemically amplified resist used in the field of microfabrication represented by the manufacture of semiconductor integrated circuits. 248 nm), ArF excimer laser (wavelength 193 nm), F ₂ excimer laser (wavelength 157 nm) or EUV (wavelength 13 nm, etc.), and other radiation sensitive acids sensitive to various types of radiation such as deep ultraviolet rays and electron beams In addition to being very suitably used as a generator, it can also be used as a photopolymerization initiator for a photocurable resin composition or the like.

Synthesis of sulfonium compound (1) The sulfonium compound (1) can be synthesized, for example, by the process shown in the following reaction formula (I). In the reaction formula (a), the substituents for each naphthalene ring are not shown.

In the reaction formula (i), 2-naphthalenethiol (i) and 2-bromonaphthalene (ii) are mixed with a base such as potassium t-butoxide and a catalytic amount of tetrakis (triphenylphosphine) palladium [Pd (PPh ₃ ) ₄ ]. To obtain di (2-naphthyl) sulfide (iii), which is oxidized with, for example, an equivalent amount of m-chloroperbenzoic acid (MCPBA) at 0 ° C. to give di (2 -Naphthyl) sulfoxide (iv) is obtained. Thereafter, this is reacted with bromotrimethylsilane (Me ₃ SiBr) at a low temperature of about −78 to 0 ° C., for example, by the method described in Non-Patent Document 1, and then the Grignard reagent (R ¹ MgBr) is used at the same temperature. (Wherein R ¹ is synonymous with R ¹ in the general formula (1)), and further acid HX (where X is an atomic group giving X ⁻ in the general formula (1)). By reacting, the sulfonium compound (1) can be synthesized.

J. Org. Chem., Vol. 43, p.5571-5573 (1988)

Each of the above reactions is usually performed in a suitable solvent.
Examples of the solvent include water, methanol, ethanol, acetone, dichloromethane, tetrahydrofuran, acetonitrile, 1-methylpyrrolidone, N, N-dimethylformamide, dichloromethane-tetrahydrofuran mixed solvent, diethyl ether, benzene, toluene, diethyl ether-toluene. A mixed solvent, a diethyl ether-benzene mixed solvent, etc. can be mentioned.
These solvents can be used alone or in admixture of two or more as long as they are compatible with each other.

Acid generator (1)
The acid generator (1) of the present invention comprises a sulfonium compound (1), and is an actinic radiation such as KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), F ₂ excimer laser (wavelength 157 nm) or It is a component that generates acid in response to various types of radiation such as (ultra) deep ultraviolet rays and electron beams represented by EUV (wavelength 13 nm, etc.), and is used in the field of microfabrication represented by the manufacture of semiconductor integrated circuits. The radiation-sensitive resin composition useful as a chemically amplified resist, particularly as a radiation-sensitive acid generator in a positive-type radiation-sensitive resin composition and a negative-type radiation-sensitive resin composition described below. Can do.

Positive-type radiation-sensitive resin composition and negative-type radiation-sensitive resin composition -radiation-sensitive acid generator-
The component (A) in the positive-type radiation-sensitive resin composition and the negative-type radiation-sensitive resin composition of the present invention comprises a radiation-sensitive acid generator containing the acid generator (1) as an essential component.
In the positive radiation sensitive resin composition and the negative radiation sensitive resin composition of the present invention, the acid generator (1) can be used alone or in admixture of two or more.

In the positive radiation sensitive resin composition and the negative radiation sensitive resin composition of the present invention, as the component (A), a radiation sensitive acid generator other than the acid generator (1) (hereinafter, “ It is preferable to use one or more types of “other acid generators”.
Examples of other acid generators include onium salt compounds, sulfone compounds, sulfonic acid ester compounds, sulfonimide compounds, disulfonyldiazomethane compounds, disulfonylmethane compounds, oxime sulfonate compounds, hydrazine sulfonate compounds, and organic halides. , Disulfone and the like.

Examples of the onium salt compounds include iodonium salts, sulfonium salts, phosphonium salts, diazonium salts, ammonium salts, pyridinium salts, and the like.
Examples of the sulfone compound include β-ketosulfone, β-sulfonylsulfone, and α-diazo compounds thereof.
Examples of the sulfonic acid ester compounds include alkyl sulfonic acid esters, haloalkyl sulfonic acid esters, aryl sulfonic acid esters, and imino sulfonates.
Moreover, as said imide sulfonate compound, the compound represented by following General formula (5) can be mentioned, for example.

〔一般式（５）において、Ｒ⁷ は１価の有機基を示し、Ｒ⁸ は２価の有機基を示す。〕

[In General Formula (5), R ⁷ represents a monovalent organic group, and R ⁸ represents a divalent organic group. ]

  Examples of the disulfonyldiazomethane include compounds represented by the following general formula (6).

〔一般式（６）において、各Ｒ⁹ は相互に独立に直鎖状もしくは分岐状の１価の脂肪族炭化水素基、シクロアルキル基、直鎖状もしくは分岐状の１価のハロゲン置換脂肪族炭化水素基、ハロゲン置換シクロアルキル基、アリール基、ハロゲン化アリール基等を示す。〕

[In the general formula (6), each R ⁹ is independently a linear or branched monovalent aliphatic hydrocarbon group, cycloalkyl group, linear or branched monovalent halogen-substituted aliphatic. A hydrocarbon group, a halogen-substituted cycloalkyl group, an aryl group, a halogenated aryl group and the like are shown. ]

  Moreover, as said disulfonylmethane compound, the compound represented by following General formula (7) can be mentioned, for example.

[In the general formula (7), each R ¹⁰ is independently a linear or branched monovalent aliphatic hydrocarbon group, cycloalkyl group, aryl group, aralkyl group, or monovalent organic having a hetero atom. V and W each independently represent an aryl group, a hydrogen atom, a linear or branched monovalent aliphatic hydrocarbon group or another monovalent organic group having a hetero atom, and V And / or W is an aryl group, V and W are connected to each other to form a monocyclic or polycyclic ring having at least one unsaturated bond, or V and W are connected to each other The following formula (i)

(However, V ′ and W ′ are independent from each other, and a plurality of V ′ and W ′ may be the same or different from each other, and may be a hydrogen atom, a halogen atom, an alkyl group, a cycloalkyl group, an aryl group or V ′ and W ′ bonded to the same or different carbon atoms, each representing an aralkyl group, are connected to each other to form a carbocyclic ring structure, and x is an integer of 2 to 10. Group is formed. ]

  Moreover, as said oxime sulfonate compound, the compound represented by the following general formula (8-1) or general formula (8-2) can be mentioned, for example.

〔一般式（８−１）および一般式（８−２）において、Ｒ¹¹およびＲ¹²は相互に独立に１価の有機基を示し、一般式（８−２）における２個のＲ¹¹および２個のＲ¹²はそれぞれ相互に同一でも異なっていてもよい。〕

[In General Formula (8-1) and General Formula (8-2), R ¹¹ and R ¹² each independently represent a monovalent organic group, and two R ¹¹ in General Formula (8-2) and Two R <^12> may mutually be same or different. ]

  Moreover, as said hydrazine sulfonate compound, the compound represented by General formula (9-1) or General formula (9-2) can be mentioned, for example.

〔一般式（９−１）および一般式（９−２）において、Ｒ¹³は１価の有機基を示し、一般式（９−２）における２個のＲ¹³は相互に同一でも異なっていてもよい。〕

[In General Formula (9-1) and General Formula (9-2), R ¹³ represents a monovalent organic group, and two R ¹³ in General Formula (9-2) may be the same or different from each other. Also good. ]

  The other acid generator in the present invention is preferably one or more members selected from the group consisting of an onium compound, a sulfonimide compound, a diazomethane compound and an oxime sulfonate compound.

  In the positive radiation sensitive resin composition and the negative radiation sensitive resin composition of the present invention, the amount of the acid generator (1) used is 100 parts by weight of the acid dissociable group-containing resin or alkali-soluble resin. Preferably it is 0.01-10 weight part, More preferably, it is 0.01-5 weight part, Most preferably, it is 0.01-4 weight part. In this case, if the amount of the acid generator (1) used is less than 0.01 parts by weight, the desired effect of the present invention may not be sufficiently achieved. May decrease.

  The amount of the other acid generator used may be variously selected according to the desired characteristics of the resist, but is preferably 0 with respect to 100 parts by weight of the acid-dissociable group-containing resin or alkali-soluble resin. 0.001 to 70 parts by weight, more preferably 0.01 to 50 parts by weight, and particularly preferably 0.1 to 20 parts by weight. In this case, the sensitivity and resolution can be further improved by setting the amount of the other acid generator used to 0.001 part by weight or more, and by setting the amount to 70 parts by weight or less, the resist coatability and pattern can be increased. Deterioration of the shape can be suppressed.

Positive type radiation sensitive resin composition- acid-dissociable group-containing resin-
The component (B) in the positive radiation sensitive resin composition of the present invention is an alkali-insoluble or hardly alkali-soluble resin having an acid-dissociable group, and becomes alkali-soluble when the acid-dissociable group is dissociated. Resin (hereinafter referred to as “acid-dissociable group-containing resin”).

  The term “alkali-insoluble or alkali-insoluble” as used herein refers to alkali development that is employed when forming a resist pattern from a resist film formed using a radiation-sensitive resin composition containing an acid-dissociable group-containing resin. When a film using only an acid-dissociable group-containing resin instead of the resist film is developed under the conditions, it means that 50% or more of the initial film thickness of the film remains after development.

The acid dissociable group in the acid dissociable group-containing resin is, for example, a group in which a hydrogen atom in an acidic functional group such as a phenolic hydroxyl group, a carboxyl group, or a sulfonic acid group is substituted, and dissociates in the presence of an acid. Means group.
Examples of such acid dissociable groups include substituted methyl groups, 1-substituted ethyl groups, 1-substituted n-propyl groups, 1-branched alkyl groups, alkoxycarbonyl groups, acyl groups, and cyclic acid dissociable groups. Etc.

  Examples of the substituted methyl group include methoxymethyl group, methylthiomethyl group, ethoxymethyl group, ethylthiomethyl group, (2-methoxyethoxy) methyl group, benzyloxymethyl group, benzylthiomethyl group, phenacyl group, 4- Bromophenacyl group, 4-methoxyphenacyl group, 4-methylthiophenacyl group, α-methylphenacyl group, cyclopropylmethyl group, benzyl group, diphenylmethyl group, triphenylmethyl group, 4-bromobenzyl group, 4-nitro Benzyl group, 4-methoxybenzyl group, 4-methylthiobenzyl group, 4-ethoxybenzyl group, 4-ethylthiobenzyl group, piperonyl group, methoxycarbonylmethyl group, ethoxycarbonylmethyl group, n-propoxycarbonylmethyl group, i- Propoxycarbonylmethyl group, - it can be exemplified butoxycarbonyl methyl group, a t- butoxycarbonyl methyl group.

  Examples of the 1-substituted ethyl group include 1-methoxyethyl group, 1-methylthioethyl group, 1,1-dimethoxyethyl group, 1-ethoxyethyl group, 1-ethylthioethyl group, 1,1- Diethoxyethyl group, 1-phenoxyethyl group, 1-phenylthioethyl group, 1,1-diphenoxyethyl group, 1-benzyloxyethyl group, 1-benzylthioethyl group, 1-cyclopropyloxyethyl group, 1 -Cyclohexyloxyethyl group, 1-phenylethyl group, 1,1-diphenylethyl group, 1-methoxycarbonylethyl group, 1-ethoxycarbonylethyl group, 1-n-propoxycarbonylethyl group, 1-i-propoxycarbonylethyl Groups, 1-n-butoxycarbonylethyl group, 1-t-butoxycarbonylethyl group, etc. Can.

Examples of the 1-substituted-n-propyl group include 1-methoxy-n-propyl group and 1-ethoxy-n-propyl group.
Examples of the 1-branched alkyl group include i-propyl group, 1-methylpropyl group, t-butyl group, 1,1-dimethylpropyl group, 1-methylbutyl group, 1,1-dimethylbutyl group, and the like. Can be mentioned.
Examples of the alkoxycarbonyl group include a methoxycarbonyl group, an ethoxycarbonyl group, an i-propoxycarbonyl group, and a t-butoxycarbonyl group.

  Examples of the acyl group include acetyl group, propionyl group, butyryl group, heptanoyl group, hexanoyl group, valeryl group, pivaloyl group, isovaleryl group, laurylyl group, myristoyl group, palmitoyl group, stearoyl group, oxalyl group, malonyl Group, succinyl group, glutaryl group, adipoyl group, piperoyl group, suberoyl group, azelaoil group, sebacoyl group, acryloyl group, propioyl group, methacryloyl group, crotonoyl group, oleoyl group, maleoyl group, fumaroyl group, mesaconoyl group, canphoroyl group Benzoyl group, phthaloyl group, isophthaloyl group, terephthaloyl group, naphthoyl group, toluoyl group, hydroatropoyl group, atropoyl group, cinnamoyl group, furoyl group, thenoyl group, nicotinoyl group Isonicotinoyl group, p- toluenesulfonyl group, and mesyl group.

  Examples of the cyclic acid dissociable group include a cyclopropyl group, a cyclopentyl group, a cyclohexyl group, a cyclohexenyl group, a 4-methoxycyclohexyl group, a tetrahydropyranyl group, a tetrahydrofuranyl group, a tetrahydrothiopyranyl group, and a tetrahydro group. A thiofuranyl group, 3-bromotetrahydropyranyl group, 4-methoxytetrahydropyranyl group, 4-methoxytetrahydrothiopyranyl group, 3-tetrahydrothiophene-1,1-dioxide group and the like can be mentioned.

  Among these acid dissociable groups, benzyl group, t-butoxycarbonylmethyl group, 1-methoxyethyl group, 1-ethoxyethyl group, 1-cyclohexyloxyethyl group, 1-ethoxy-n-propyl group, t-butyl Group, 1,1-dimethylpropyl group, t-butoxycarbonyl group, tetrahydropyranyl group, tetrahydrofuranyl group, tetrahydrothiopyranyl group, tetrahydrothiofuranyl group and the like are preferable.

In the acid-dissociable group-containing resin, one or more acid-dissociable groups can be present.
The rate of introduction of acid-dissociable groups in the acid-dissociable group-containing resin (the ratio of the number of acid-dissociable groups to the total number of acid functional groups and acid-dissociable groups in the acid-dissociable group-containing resin) Although it can select suitably by the kind of resin and the resin in which this group is introduce | transduced, Preferably it is 5 to 100%, More preferably, it is 10 to 100%.

  Further, the structure of the acid-dissociable group-containing resin is not particularly limited as long as it has the above-described properties, and various structures can be used. In particular, a hydrogen atom of a phenolic hydroxyl group in poly (p-hydroxystyrene) A hydrogen atom of a phenolic hydroxyl group in a resin obtained by substituting a part or all of an acid dissociable group, p-hydroxystyrene and / or a copolymer of p-hydroxy-α-methylstyrene and (meth) acrylic acid, and A resin or the like in which part or all of the hydrogen atoms of the carboxyl group are substituted with acid dissociable groups is preferred.

In addition, the structure of the acid-dissociable group-containing resin can be variously selected according to the type of radiation used.
For example, as an acid dissociable group-containing resin particularly suitable for a radiation-sensitive resin composition using a KrF excimer laser, for example, a repeating unit represented by the following general formula (10) (hereinafter referred to as “repeating unit (10)”) And an insoluble or hardly alkali-soluble resin (hereinafter referred to as “resin (B1)”) having a repeating unit in which the phenolic hydroxyl group in the repeating unit (10) is protected with an acid-dissociable group. The resin (B1) is, ArF excimer laser, F ₂ excimer laser can also be suitably used in radiation-sensitive resin compositions using other radiation such as electron beams.

〔一般式（１０）において、Ｒ¹⁴は水素原子または１価の有機基を示し、複数存在する
Ｒ¹⁴は相互に同一でも異なってもよく、ａおよびｂはそれぞれ１〜３の整数である。〕

[In General Formula (10), R ¹⁴ represents a hydrogen atom or a monovalent organic group, a plurality of R ¹⁴ may be the same as or different from each other, and a and b are each an integer of 1 to 3. ]

  As the repeating unit (10), a unit in which a non-aromatic double bond of p-hydroxystyrene is cleaved is particularly preferable.

Further, the resin (B1) may further contain one or more other repeating units.
Examples of the other repeating unit include vinyl aromatic compounds such as styrene; (meth) acrylic acid such as t-butyl (meth) acrylate, adamantyl (meth) acrylate, and 2-methyladamantyl (meth) acrylate. Examples include units in which polymerizable unsaturated bonds such as esters are cleaved.

Moreover, as an acid dissociable group containing resin especially suitable for a radiation sensitive resin composition using an ArF excimer laser, for example, a repeating unit represented by the following general formula (11-1) (hereinafter referred to as “repeating unit (11 -1) ") and at least one selected from the group of repeating units represented by the following general formula (11-2) (hereinafter referred to as" repeating units (11-2) "), and An alkali-insoluble or alkali-soluble resin (hereinafter referred to as “resin (B2)” containing at least one repeating unit represented by the following general formula (11-3) (hereinafter referred to as “repeating unit (11-3)”). ) ") Is preferred. The resin (B2) may also be suitably used in KrF excimer laser, F ₂ excimer laser radiation-sensitive resin composition using other radiation such as electron beams.

[In General Formula (11-1), General Formula (11-2), and General Formula (11-3), R ¹⁵ , R ^18, and R ¹⁹ each independently represent a hydrogen atom or a methyl group, 11-1), each R ¹⁶ is independently a hydrogen atom, a hydroxyl group, a cyano group or a —COOR ¹⁷ group (where R ¹⁷ is a hydrogen atom, a linear or branched alkyl having 1 to 4 carbon atoms). In the general formula (11-3), each R ²⁰ is independently a monovalent alicyclic hydrocarbon group having 4 to 20 carbon atoms. Or a derivative thereof or a linear or branched alkyl group of 1 to 4 and at least one of R ²⁰ is the alicyclic hydrocarbon group or a derivative thereof, or any two R ²⁰ are mutually To each of the carbon atoms And a divalent alicyclic hydrocarbon group having 4 to 20 carbon atoms or a derivative thereof, together with the above R ²⁰ is a linear or branched alkyl group having 1 to 4 carbon atoms or 4 to 20 carbon atoms. Represents a monovalent alicyclic hydrocarbon group or a derivative thereof. ]

  As preferable repeating unit (11-1), for example, (meth) acrylic acid 3-hydroxyadamantan-1-yl, (meth) acrylic acid 3,5-dihydroxyadamantan-1-yl, (meth) acrylic acid 3- Cyanoadamantan-1-yl, (meth) acrylic acid 3-carboxyladamantan-1-yl, (meth) acrylic acid 3,5-dicarboxyladamantan-1-yl, (meth) acrylic acid 3-carboxyl-5-hydroxy Examples thereof include units in which a polymerizable unsaturated bond is cleaved, such as adamantane-1-yl and 3-methoxycarbonyl-5-hydroxyadamantan-1-yl (meth) acrylate.

  Moreover, as a preferable repeating unit (11-3), for example, (meth) acrylic acid 1-methyl-1-cyclopentyl, (meth) acrylic acid 1-ethyl-1-cyclopentyl, (meth) acrylic acid 1-methyl- 1-cyclohexyl, 1-ethyl-1-cyclohexyl (meth) acrylate, 2-methyladamantyl-2-yl (meth) acrylate, 2-ethyladamantyl-2-yl (meth) acrylate, (meth) acrylic acid Polymerizability of 2-n-propyladamantyl-2-yl, 2-methacrylic acid 2-i-propyladamantyl-2-yl, 1- (adamantan-1-yl) -1-methylethyl (meth) acrylate, etc. Mention may be made of units in which unsaturated bonds are cleaved.

The resin (B2) may further contain one or more other repeating units.
Examples of the other repeating units include (meth) acrylic acid 7-oxo-6-oxabicyclo [3.2.1] octane-4-yl, (meth) acrylic acid 2-oxotetrahydropyran-4-yl. (Meth) acrylic acid 4-methyl-2-oxotetrahydropyran-4-yl, (meth) acrylic acid 5-oxotetrahydrofuran-3-yl, (meth) acrylic acid 2-oxotetrahydrofuran-3-yl, (meta ) Acrylic acid 5-oxotetrahydrofuran-2-ylmethyl, (meth) acrylic acid (3,3-dimethyl-5-oxotetrahydrofuran-2-yl) methyl, (meth) acrylamide, N, N-dimethyl (meth) Acrylamide, crotonamide, maleamide, fumaramide, mesaconamide, citraconic amide, Unsaturated amide compounds such as Kon'amido; maleic anhydride, unsaturated carboxylic acid anhydrides such as itaconic anhydride; bicyclo [2.2.1] hept-2-ene or derivatives thereof; tetracyclo [6.2.1 ^{3 , 6} . 0 ^2,7 ] monofunctional monomers such as dodec-3-ene or derivatives thereof, methylene glycol di (meth) acrylate, ethylene glycol di (meth) acrylate, 2,5-dimethyl-2,5-hexane Diol di (meth) acrylate, 1,2-adamantanediol di (meth) acrylate, 1,3-adamantanediol di (meth) acrylate, 1,4-adamantanediol di (meth) acrylate, tricyclodecanyl dimethylol di Examples include units in which a polymerizable unsaturated bond of a polyfunctional monomer such as (meth) acrylate is cleaved.

Furthermore, as an acid-dissociable group-containing resin particularly suitable for a radiation-sensitive resin composition using an F ₂ excimer laser, a repeating unit represented by the following general formula (12) (hereinafter referred to as “repeating unit (12)”) And / or alkali-insoluble or alkali-insoluble polysiloxane (hereinafter referred to as “resin (B3)”) having a repeating unit represented by the general formula (13). The resin (B3) can also be suitably used when other radiation such as a KrF excimer laser, an ArF excimer laser, or an electron beam is used.

〔一般式（１２）および一般式（１３）において、各Ｅは相互に独立に酸解離性基を有する１価の有機基を示し、Ｒ²¹は置換もしくは無置換の炭素数１〜２０の直鎖状、分岐状もしくは環状の１価の炭化水素基を示す。〕

[In General Formula (12) and General Formula (13), each E independently represents a monovalent organic group having an acid dissociable group, and R ²¹ is a substituted or unsubstituted straight chain having 1 to 20 carbon atoms. A chain, branched or cyclic monovalent hydrocarbon group is shown. ]

E in general formula (12) and general formula (13) is preferably a group having a structure in which an acid dissociable group is bonded to a group having an alicyclic ring.
Examples of the group having an alicyclic ring include a group having an alicyclic ring derived from a cycloalkane having 3 to 8 carbon atoms, norbornane, tricyclodecane, tetracyclododecane, adamantane, or the like, or a group having 6 to 20 carbon atoms. A group having a halogenated aromatic ring is preferred.

As the resin (B3), a resin having a repeating unit (12) is preferable.
Specific examples of the particularly preferred repeating unit (12) include units represented by the following formulas (12-1) to (12-4).

The resin (B3) may further contain one or more other repeating units.
Examples of the other repeating units include units formed by hydrolysis of alkylalkoxysilanes such as methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, and ethyltriethoxysilane, and the following formula (14- The repeating units represented by 1) to (14-4) are preferred.

The resin (B3) can be produced by polycondensing a silane compound having an acid-dissociable group or by introducing an acid-dissociable group into a polysiloxane produced in advance.
When polycondensating a silane compound having an acid dissociable group, it is preferable to use an acidic catalyst as the catalyst. In particular, after the polycondensation of the silane compound in the presence of an acidic catalyst, a basic catalyst is added. Further reaction is preferable.

Examples of the acidic catalyst include inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid, boric acid, phosphoric acid, titanium tetrachloride, zinc chloride, and aluminum chloride; formic acid, acetic acid, n-propionic acid, butyric acid, valeric acid, oxalic acid, List of organic acids such as malonic acid, succinic acid, maleic acid, fumaric acid, adipic acid, phthalic acid, terephthalic acid, acetic anhydride, maleic anhydride, citric acid, benzenesulfonic acid, p-toluenesulfonic acid, methanesulfonic acid be able to.
Of these acidic catalysts, hydrochloric acid, sulfuric acid, acetic acid, oxalic acid, malonic acid, maleic acid, fumaric acid, acetic anhydride, maleic anhydride and the like are preferable.
The acidic catalyst can be used alone or in admixture of two or more.

Examples of the basic catalyst include inorganic bases such as lithium hydroxide, sodium hydroxide, potassium hydroxide, calcium hydroxide, barium hydroxide, sodium hydrogen carbonate, potassium hydrogen carbonate, sodium carbonate, and potassium carbonate; Examples thereof include organic bases such as triethylamine, tri-n-propylamine, tri-n-butylamine, and pyridine.
The basic catalysts can be used alone or in admixture of two or more.

When the acid-dissociable group-containing resin is produced by polymerization of a polymerizable unsaturated monomer or through the polymerization, the resin is derived from a polyfunctional monomer having two or more polymerizable unsaturated bonds. A branched structure can be introduced by a unit and / or an acetal crosslinking group. By introducing such a branched structure, the heat resistance of the acid-dissociable group-containing resin can be improved.
In this case, the introduction rate of the branched structure in the (B) acid-dissociable group-containing resin can be appropriately selected depending on the branched structure and the type of resin into which the branched structure is introduced. % Or less is preferable.

  The molecular weight of the acid-dissociable group-containing resin is not particularly limited and may be appropriately selected. The polystyrene-reduced weight molecular weight (hereinafter referred to as “Mw”) measured by gel permeation chromatography (GPC) is usually used. 1,000 to 500,000, preferably 2,000 to 400,000, and more preferably 3,000 to 300,000.

  The acid dissociable group-containing resin having no branched structure preferably has an Mw of 1,000 to 150,000, more preferably 3,000 to 100,000, and contains an acid dissociable group having a branched structure. The Mw of the resin is preferably 5,000 to 500,000, more preferably 8,000 to 300,000. By using an acid-dissociable group-containing resin having Mw in such a range, the resulting resist has excellent development performance.

  Further, the ratio (Mw / Mn) between the Mw of the acid-dissociable group-containing resin and the polystyrene-reduced number molecular weight (hereinafter referred to as “Mn”) measured by GPC is not particularly limited and can be appropriately selected. Usually, 1 to 10, preferably 1 to 8, and more preferably 1 to 5. By using the acid-dissociable group-containing resin having Mw / Mn in such a range, the resulting resist has excellent resolution performance.

  Although there is no limitation in particular about the manufacturing method of acid dissociable group containing resin, For example, it is 1 in the acidic functional group in the alkali-soluble resin manufactured previously (for example, alkali-soluble resin in the negative radiation sensitive resin composition mentioned later). A method for introducing one or more acid-dissociable groups; a method for polymerizing one or more polymerizable unsaturated monomers having an acid-dissociable group, optionally together with another polymerizable unsaturated monomer; One or more polycondensable components having a functional group can be produced by a method such as polycondensation, optionally together with other polycondensable components.

Polymerization of the polymerizable unsaturated monomer and the polymerization of one or more polymerizable unsaturated monomers having an acid dissociable group in the production of the alkali-soluble resin may be carried out by using the polymerizable unsaturated monomer used Depending on the type of reaction medium, etc., a polymerization initiator such as a radical polymerization initiator, an anionic polymerization catalyst, a coordination anionic polymerization catalyst, a cationic polymerization catalyst, or a polymerization catalyst is appropriately selected, bulk polymerization, solution polymerization, precipitation polymerization, It can implement by appropriate polymerization forms, such as emulsion polymerization, suspension polymerization, and block-suspension polymerization.
The polycondensation of one or more polycondensable components having an acid dissociable group can be preferably carried out in an aqueous medium or a mixed medium of water and a hydrophilic solvent in the presence of an acid catalyst.

Negative type radiation sensitive resin composition- alkali-soluble resin-
The component (C) in the negative radiation-sensitive resin composition of the present invention is a functional group having affinity with an alkaline developer, for example, one oxygen-containing functional group such as a phenolic hydroxyl group, an alcoholic hydroxyl group, or a carboxyl group. It consists of an alkali-soluble resin.
Examples of such alkali-soluble resins include resins having at least one repeating unit represented by the following general formulas (15) to (17).

〔一般式（１５）および一般式（１６）において、Ｒ²²およびＲ²⁵は相互に独立に水素原子またはメチル基を示し、一般式（１５）において、Ｒ²³はヒドロキシル基、カルボキシル基、−Ｒ²⁴ＣＯＯＨ、−ＯＲ²⁴ＣＯＯＨ、−ＯＣＯＲ²⁴ＣＯＯＨまたは
−ＣＯＯＲ²⁴ＣＯＯＨ（但し、各Ｒ²⁴は相互に独立に−（ＣＨ₂)_j −を示し、ｊは１〜４の整数である。）を示す。〕

[In General Formula (15) and General Formula (16), R ²² and R ²⁵ independently represent a hydrogen atom or a methyl group, and in General Formula (15), R ²³ represents a hydroxyl group, a carboxyl group, —R ²⁴ COOH, —OR ²⁴ COOH, —OCOR ²⁴ COOH, or —COOR ²⁴ COOH (wherein each R ²⁴ independently represents — (CH ₂ ) _j —, j is an integer of 1 to 4). Show. ]

The alkali-soluble resin may be composed only of the repeating units represented by the general formulas (15) to (17). However, as long as the generated resin is soluble in an alkali developer, other repeating units are used. 1 or more types can be further included.
As said other repeating unit, the unit similar to the other repeating unit in the said resin (B1) etc. can be mentioned, for example.

  The content of the repeating units represented by the general formulas (15) to (17) in the alkali-soluble resin cannot be defined unconditionally depending on the types of other repeating units contained in some cases, but preferably 10 to 100 mol%. More preferably, it is 20-100 mol%.

  When the alkali-soluble resin has a repeating unit containing a carbon-carbon unsaturated bond represented by the general formula (15) or the like, it can also be used as a hydrogenated product. The hydrogenation rate in this case is usually 70% or less, preferably 50% or less, more preferably 40% or less, of the carbon-carbon unsaturated bond contained in the repeating unit represented by the general formula (15) or the like. It is. If the hydrogenation rate in the alkali-soluble resin exceeds 70%, the developability with an alkali developer may be lowered.

  Examples of the alkali-soluble resin in the negative radiation sensitive resin composition include poly (p-hydroxystyrene), p-hydroxystyrene / p-hydroxy-α-methylstyrene copolymer, and p-hydroxystyrene / styrene copolymer. A resin mainly composed of coalescence or the like is preferable.

The Mw of the alkali-soluble resin varies depending on the desired properties of the negative radiation-sensitive resin composition, but is preferably 1,000 to 150,000, more preferably 3,000 to 100,000.
The alkali-soluble resins can be used alone or in admixture of two or more.

-Crosslinking agent-
(D) component in the negative radiation sensitive resin composition of this invention consists of a crosslinking agent which makes alkali-soluble resin an alkali hardly soluble or insoluble by the effect | action of an acid.
As such a crosslinking agent, for example, a compound having at least one functional group having crosslinking reactivity with an alkali-soluble resin (hereinafter referred to as “crosslinkable functional group”) can be given.

  Examples of the crosslinkable functional group include a glycidyl ether group, a glycidyl ester group, a glycidylamino group, a methoxymethyl group, an ethoxymethyl group, a benzyloxymethyl group, an acetoxymethyl group, a benzoyloxymethyl group, a formyl group, and an acetyl group. , Vinyl group, isopropenyl group, (dimethylamino) methyl group, (diethylamino) methyl group, (dimethylolamino) methyl group, (diethylolamino) methyl group, morpholinomethyl group, and the like.

  Examples of the crosslinking agent include bisphenol A epoxy compounds, bisphenol F epoxy compounds, bisphenol S epoxy compounds, novolac resin epoxy compounds, resole resin epoxy compounds, poly (hydroxystyrene) epoxy compounds, and methylol group-containing melamine. Compound, methylol group-containing benzoguanamine compound, methylol group-containing urea compound, methylol group-containing phenol compound, alkoxyalkyl group-containing melamine compound, alkoxyalkyl group-containing benzoguanamine compound, alkoxyalkyl group-containing urea compound, alkoxyalkyl group-containing phenol compound, carboxymethyl Group-containing melamine resin, carboxymethyl group-containing benzoguanamine resin, carboxymethyl group-containing urea resin, carboxymethyl group-containing Phenol resins, carboxymethyl group-containing melamine compounds, carboxymethyl group-containing benzoguanamine compounds, carboxymethyl group-containing urea compounds, mention may be made of carboxymethyl group-containing phenol compounds and the like.

  Among these crosslinking agents, methylol group-containing phenol compounds, methoxymethyl group-containing melamine compounds, methoxymethyl group-containing phenol compounds, methoxymethyl group-containing glycoluril compounds, methoxymethyl group-containing urea compounds and acetoxymethyl group-containing phenol compounds are preferred. More preferred are methoxymethyl group-containing melamine compounds (for example, hexamethoxymethyl melamine), methoxymethyl group-containing glycoluril compounds, methoxymethyl group-containing urea compounds, and the like. Methoxymethyl group-containing melamine compounds are trade names such as CYMEL300, 301, 303, and 305 (above, manufactured by Mitsui Cyanamid Co., Ltd.), and methoxymethyl group-containing glycoluril compounds are CYMEL1174 (manufactured by Mitsui Cyanamid Co., Ltd.). In addition, methoxymethyl group-containing urea compounds are commercially available under trade names such as MX290 (manufactured by Sanwa Chemical Co., Ltd.).

Moreover, as the crosslinking agent, a resin imparted with a property as a crosslinking agent by substituting the hydrogen atom of the oxygen-containing functional group in the alkali-soluble resin with the crosslinking functional group can be suitably used.
The introduction rate of the crosslinkable functional group in this case cannot be unconditionally defined by the type of the crosslinkable functional group or the alkali-soluble resin into which the group is introduced, but with respect to the total oxygen-containing functional group in the alkali-soluble resin, Usually, it is 5 to 60 mol%, preferably 10 to 50 mol%, more preferably 15 to 40 mol%. In this case, when the introduction ratio of the crosslinkable functional group is less than 5 mol%, the remaining film ratio tends to decrease, the pattern meanders or swells easily. There exists a tendency for developability to fall.

  In the negative radiation-sensitive resin composition of the present invention, the amount of the crosslinking agent used is preferably 5 to 95 parts by weight, more preferably 15 to 85 parts by weight, particularly preferably 100 parts by weight of the alkali-soluble resin. 20 to 75 parts by weight. In this case, when the amount of the crosslinking agent used is less than 5 parts by weight, the crosslinking reaction is generally insufficient, and there is a possibility that the remaining film ratio is lowered, the pattern meanders or swells. Tends to increase and alkali developability tends to decrease.

Additive- Acid diffusion inhibitor-
The positive-type radiation-sensitive resin composition and the negative-type radiation-sensitive resin composition of the present invention control the diffusion phenomenon in the resist film of the acid generated from the radiation-sensitive acid generator by exposure, and in the non-exposed area. It is preferable to add an acid diffusion controller having an action of suppressing undesirable chemical reactions. By blending such an acid diffusion control agent, the storage stability of the radiation-sensitive resin composition can be further improved, the resolution performance as a resist is further improved, and from exposure to development processing Changes in the line width of the resist pattern due to fluctuations in the holding time (PED) can be suppressed, and as a result, a radiation-sensitive resin composition having extremely excellent process stability can be obtained.

As such an acid diffusion controller, a nitrogen-containing organic compound whose basicity is not changed by exposure or heat treatment in the resist pattern forming step is preferable.
Examples of the nitrogen-containing organic compound include a compound represented by the following general formula (18) (hereinafter referred to as “nitrogen-containing compound (I)”), a diamino compound having two nitrogen atoms in the same molecule (hereinafter referred to as “nitrogen-containing compound (I)”). , "Nitrogen-containing compound (II)"), polyamino compounds and polymers having three or more nitrogen atoms (hereinafter referred to as "nitrogen-containing compound (III)"), amide group-containing compounds, urea compounds, nitrogen-containing compounds A heterocyclic compound etc. can be mentioned.

〔一般式（１８）において、各Ｒ²⁶は相互に独立に水素原子、アルキル基、アリール基またはアラルキル基を示し、これらの各基は置換されていてもよい。〕

[In the general formula (18), each R ²⁶ independently represents a hydrogen atom, an alkyl group, an aryl group or an aralkyl group, and each of these groups may be substituted. ]

In the general formula (18), examples of the optionally substituted alkyl group represented by R ²⁶ include a group having 1 to 15 carbon atoms, preferably 1 to 10 carbon atoms, specifically, a methyl group, an ethyl group, n -Propyl group, i-propyl group, n-butyl group, 2-methylpropyl group, 1-methylpropyl group, t-butyl group, n-pentyl group, neopentyl group, n-hexyl group, n-heptyl group, An n-octyl group, n-ethylhexyl group, n-nonyl group, n-decyl group, etc. can be mentioned.

Examples of the optionally substituted aryl group for R ²⁶ include a group having 6 to 12 carbon atoms, specifically a phenyl group, an o-tolyl group, an m-tolyl group, a p-tolyl group, 2 , 3-xylyl group, 2,4-xylyl group, 2,5-xylyl group, 2,6-xylyl group, 3,4-xylyl group, 3,5-xylyl group, p-cumenyl group, 1-naphthyl group Etc.

Furthermore, as the aralkyl group which may be substituted for R ²⁶ , for example, a group having 7 to 19 carbon atoms, preferably 7 to 13 carbon atoms, specifically, a benzyl group, an α-methylbenzyl group, a phenethyl group. And 1-naphthylmethyl group.

  Examples of the nitrogen-containing compound (I) include monoalkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine; di-n-butylamine, di-n -Dialkylamines such as pentylamine, di-n-hexylamine, di-n-heptylamine, di-n-octylamine, di-n-nonylamine, di-n-decylamine; triethylamine, tri-n-propylamine , Tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decylamine, etc. Amines; aniline, N-methylaniline, N, N-dimethylaniline, 2-methylaniline, 3 Methylaniline, 4-methylaniline, 4-nitroaniline, diphenylamine, triphenylamine, aromatic amines such as 1-naphthylamine; ethanolamine, diethanolamine, can be exemplified alkanolamines such as triethanolamine and the like.

  Examples of the nitrogen-containing compound (II) include ethylenediamine, N, N, N ′, N′-tetramethylethylenediamine, tetramethylenediamine, hexamethylenediamine, N, N, N ′, N′-tetrakis (2- Hydroxyethyl) ethylenediamine, N, N, N ′, N′-tetrakis (2-hydroxypropyl) ethylenediamine, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenyl ether, 4,4′-diaminobenzophenone, 4, 4'-diaminodiphenylamine, 2,2'-bis (4-aminophenyl) propane, 2- (3-aminophenyl) -2- (4-aminophenyl) propane, 2- (4-aminophenyl) -2- (3-hydroxyphenyl) propane, 2- (4-aminophenyl) -2- (4-hydro Xylphenyl) propane, 1,4-bis [1- (4-aminophenyl) -1-methylethyl] benzene, 1,3-bis [1- (4-aminophenyl) -1-methylethyl] benzene, etc. be able to.

  Examples of the nitrogen-containing compound (III) include polyethyleneimine, polyallylamine, N- (2-dimethylaminoethyl) acrylamide polymer, and the like.

  Examples of the amide group-containing compound include formamide, N-methylformamide, N, N-dimethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, propionamide, benzamide, pyrrolidone, N-methylpyrrolidone and the like. Can be mentioned.

  Examples of the urea compound include urea, methylurea, 1,1-dimethylurea, 1,3-dimethylurea, 1,1,3,3-tetramethylurea, 1,3-diphenylurea, tributylthiourea and the like. be able to.

  Examples of the nitrogen-containing heterocyclic compound include imidazole, benzimidazole, 2-methylimidazole, 4-methylimidazole, 1,2-dimethylimidazole, 2-phenylimidazole, 4-phenylimidazole, 4-methyl-2- Imidazoles such as phenylimidazole and 2-phenylbenzimidazole; pyridine, 2-methylpyridine, 4-methylpyridine, 2-ethylpyridine, 4-ethylpyridine, 2-phenylpyridine, 4-phenylpyridine, 2-methyl-4 -In addition to pyridines such as phenylpyridine, nicotine, nicotinic acid, nicotinamide, quinoline, 8-oxyquinoline, acridine, pyrazine, pyrazole, pyridazine, quinosaline, purine, pyrrolidine, piperidine, 1-piperidineethanol, - piperidineethanol, morpholine, 4-methylmorpholine, piperazine, 1,4-dimethylpiperazine, and 1,4-diazabicyclo [2.2.2] octane.

  Moreover, the compound which has an acid dissociable group can also be used as a nitrogen-containing organic compound.

  Examples of the nitrogen-containing organic compound having an acid dissociable group include N- (t-butoxycarbonyl) piperidine, N- (t-butoxycarbonyl) imidazole, N- (t-butoxycarbonyl) benzimidazole, N- ( t-butoxycarbonyl) -2-phenylbenzimidazole, N- (t-butoxycarbonyl) di-n-octylamine, N- (t-butoxycarbonyl) diethanolamine, N- (t-butoxycarbonyl) dicyclohexylamine, N- And (t-butoxycarbonyl) diphenylamine.

Of these nitrogen-containing organic compounds, nitrogen-containing compounds (I), nitrogen-containing compounds (II), nitrogen-containing heterocyclic compounds, nitrogen-containing organic compounds having an acid-dissociable group are preferred.
The acid diffusion controller can be used alone or in admixture of two or more.

  The compounding amount of the acid diffusion controller is preferably 15 parts by mass or less, more preferably 0.001 to 10 parts by mass, and particularly preferably 0.005 with respect to 100 parts by mass of the acid dissociable group-containing resin or alkali-soluble resin. -5 parts by mass. In this case, by setting the compounding amount of the acid diffusion controller to 0.001 part by mass or more, it is possible to suppress a decrease in pattern shape and dimensional fidelity due to process conditions. The alkali developability of the part can be further improved.

-Dissolution control agent-
The positive-type radiation-sensitive resin composition and the negative-type radiation-sensitive resin composition of the present invention can be blended with a dissolution control agent having a property of increasing the solubility in an alkali developer by the action of an acid.
As such a dissolution control agent, for example, a compound having an acidic functional group such as a phenolic hydroxyl group, a carboxyl group, or a sulfonic acid group, or a compound in which the hydrogen atom of the acidic functional group in the compound is substituted with an acid dissociable group Etc.
The said dissolution control agent can be used individually or in mixture of 2 or more types.

  The blending amount of the dissolution control agent is usually 40 parts by weight or less, preferably 20 parts by weight or less with respect to 100 parts by weight of the acid-dissociable group-containing resin or alkali-soluble resin.

-Surfactant-
The positive-type radiation-sensitive resin composition and the negative-type radiation-sensitive resin composition of the present invention are blended with a surfactant exhibiting the action of improving the coating property, striation, developability, etc. of the radiation-sensitive resin composition. You can also
As such a surfactant, any of anionic, cationic, nonionic or amphoteric surfactants can be used, but nonionic surfactants are preferred.

Examples of the nonionic surfactant include polyoxyethylene higher alkyl ethers, polyoxyethylene higher alkyl phenyl ethers, polyethylene glycol higher fatty acid diesters, and the following trade names “KP” (Shin-Etsu Chemical Co., Ltd.). "Polyflow" (manufactured by Kyoeisha Chemical Co., Ltd.), "F Top" (manufactured by Tochem Products), "MegaFuck" (manufactured by Dainippon Ink & Chemicals, Inc.), "Fluorard" ( Sumitomo 3M Co., Ltd.), “Asahi Guard”, “Surflon” (above, manufactured by Asahi Glass Co., Ltd.) and the like.
The surfactants can be used alone or in admixture of two or more.

  The compounding amount of the surfactant is usually 2 parts by weight or less, preferably 1.5 parts by weight or less as an active ingredient of the surfactant with respect to 100 parts by weight of the acid-dissociable group-containing resin or alkali-soluble resin.

-Sensitizer-
The positive-type radiation-sensitive resin composition and the negative-type radiation-sensitive resin composition of the present invention absorbs radiation energy and transmits the energy to the radiation-sensitive acid generator, thereby generating an amount of acid. A sensitizer capable of increasing the apparent sensitivity and improving the apparent sensitivity of the radiation-sensitive resin composition can be blended.
Examples of such sensitizers include acetophenones, benzophenones, naphthalene, biacetyl, eosin, rose bengal, pyrenes, anthracenes, phenothiazines and the like.
The said sensitizer can be used individually or in mixture of 2 or more types.

  The blending amount of the sensitizer is usually 50 parts by weight or less, preferably 30 parts by weight or less with respect to 100 parts by weight of the acid-dissociable group-containing resin or alkali-soluble resin.

Preparation of Composition Solution The positive-type radiation-sensitive resin composition and the negative-type radiation-sensitive resin composition of the present invention are usually prepared by dissolving each component in a solvent at the time of use to obtain a uniform solution. A composition solution is prepared by filtering with a filter having a pore size of about 0.2 μm.
Examples of the solvent include ethers, esters, ether esters, ketones, ketone esters, amides, amide esters, lactams, (halogenated) hydrocarbons, and the like. Specifically, ethylene glycol monoalkyl ethers, diethylene glycol dialkyl ethers, propylene glycol monoalkyl ethers, propylene glycol dialkyl ethers, ethylene glycol monoalkyl ether acetates, propylene glycol monoalkyl ether acetates, acetates, hydroxy Acetic acid esters, lactic acid esters, alkoxyacetic acid esters, (non) cyclic ketones, acetoacetic acid esters, pyruvic acid esters, propionic acid esters, (substituted) butyric acid ester S, N, N- dialkyl formamides, N, N- dialkyl acetamides, N- alkylpyrrolidones, (halogenated) aliphatic hydrocarbons, and (halogenated) aromatic hydrocarbons, and the like.

  Specific examples of the solvent include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-propyl ether, ethylene glycol mono-n-butyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol di-n-propyl ether. , Diethylene glycol di-n-butyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol mono-n-propyl ether acetate, isopropenyl acetate, isopropenyl Propionate Toluene, xylene, methyl ethyl ketone, cyclohexanone, 2-heptanone, 3-heptanone, 4-heptanone, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, 2-hydroxy- Methyl 3-methylbutyrate, methyl lactate, ethyl lactate, n-propyl lactate, i-propyl lactate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, 3-methyl-3-methoxybutylpropionate, 3-methyl-3-methoxybutyl butyrate, ethyl acetate, n-propyl acetate, n-butyl acetate, methyl acetoacetate, ethyl acetoacetate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropion Methyl acid, - ethyl ethoxypropionate, N- methylpyrrolidone, N, N- dimethylformamide, N, it may be mentioned N- dimethylacetamide.

Among these solvents, propylene glycol monoalkyl ether acetates, 2-heptanone, lactic acid esters, 2-hydroxypropionic acid esters, 3-alkoxypropionic acid esters, etc. have good in-plane uniformity during coating. Is preferable in that.
The said solvent can be used individually or in mixture of 2 or more types.

If necessary, other solvents such as benzyl ethyl ether, di-n-hexyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, acetonyl acetone, isophorone, caproic acid, caprylic acid, 1- Use high-boiling solvents such as octanol, 1-nonanol, benzyl alcohol, benzyl acetate, ethyl benzoate, diethyl oxalate, diethyl maleate, γ-butyrolactone, ethylene carbonate, propylene carbonate, ethylene glycol monophenyl ether acetate, etc. Can do.
These other solvents can be used alone or in admixture of two or more.
The proportion of other solvents used is usually 50% by weight or less, preferably 30% by weight or less, based on the total solvent.

  The total amount of the solvent used is such that the total solid content of the solution is usually 5 to 50% by weight, preferably 10 to 50% by weight, more preferably 10 to 40% by weight, particularly preferably 10 to 30% by weight. The amount is 10 to 25% by weight. By setting the total solid content concentration of the solution within this range, it is preferable in that the uniformity within the film surface during coating is improved.

Formation of resist pattern When forming a resist pattern from the positive-type radiation-sensitive resin composition and the negative-type radiation-sensitive resin composition of the present invention, the composition solution prepared as described above is spin-coated, The resist film is formed by applying on a substrate such as a silicon wafer, a wafer coated with aluminum, an aluminum substrate, a chrome substrate for a photomask, or the like by an appropriate application means such as casting coating or roll coating. Thereafter, PB is performed in advance in some cases, and then the resist film is exposed through a predetermined mask pattern.

The radiation that can be used in the exposure includes the emission line spectrum of a mercury lamp (wavelength 254 nm), KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength), depending on the type of radiation-sensitive acid generator used. 193 nm), EUV (wavelength 13 nm, etc.) and other (super) far ultraviolet rays, synchrotron radiation X-rays such as synchrotron radiation, charged particle beams such as electron beams, etc., preferably far ultraviolet rays and charged particle beams, A KrF excimer laser, an ArF excimer laser and an electron beam are preferred.
The exposure conditions such as the radiation dose are appropriately selected according to the composition of each radiation-sensitive resin composition, the type of additive, and the like.

In forming a resist pattern, it is preferable to perform PEB after exposure from the viewpoint of improving the apparent sensitivity of the resist.
The heating conditions for PEB vary depending on the composition of each radiation-sensitive resin composition, the type of additive, etc., but are usually 30 to 200 ° C., preferably 50 to 150 ° C.

Then, a predetermined resist pattern is formed by developing the exposed resist film with an alkaline developer.
Examples of the alkali developer include alkali metal hydroxides, aqueous ammonia, alkylamines, alkanolamines, heterocyclic amines, tetraalkylammonium hydroxides, choline, 1,8-diazabicyclo [5.4. 0.0] -7-undecene, 1,5-diazabicyclo [4.3.0] -5-nonene and the like, an alkaline aqueous solution in which one or more alkaline compounds are dissolved is used. An aqueous solution of ammonium hydroxides.

The concentration of the alkaline aqueous solution is preferably 10% by weight or less, more preferably 1 to 10% by weight, and particularly preferably 2 to 5% by weight. In this case, by setting the concentration of the alkaline aqueous solution to 10% by weight or less, dissolution of the non-exposed portion in the alkaline developer can be suppressed.
In addition, it is preferable to add an appropriate amount of a surfactant or the like to the alkali developer, whereby the wettability of the alkali developer with respect to the resist can be improved.
In addition, after developing with an alkali developing solution, it is generally washed with water and dried.

  The positive-type radiation-sensitive resin composition and the negative-type radiation-sensitive resin composition of the present invention have a radiation reflectivity of a silicon substrate, an aluminum substrate, a chrome substrate for a photomask, etc., particularly in exposure with a KrF excimer laser (248 nm). Even when a high substrate is used, problems such as standing wave effect, halation effect, swing curve, etc. can be effectively prevented, the pattern shape is excellent, and sensitivity, storage stability, etc. are excellent. It is useful as a chemically amplified resist to be used.

  The sulfonium compound (1) of the present invention has a strong absorption having an absorption maximum in the vicinity of a wavelength of 248 nm, and has a photobleaching property by KrF excimer laser exposure. In particular, the positive-type radiation-sensitive resin composition and It can be used very suitably as a radiation sensitive acid generator in a negative radiation sensitive resin composition.

Hereinafter, embodiments of the present invention will be described more specifically with reference to examples of the present invention. However, the present invention is not limited to these examples.
[Synthesis of sulfonium compound (1)]
Example 1
A 500-ml three-necked flask equipped with a cooling tube and an inlet and outlet for nitrogen gas was replaced with nitrogen, and 100 ml of n-butanol degassed in advance, 4.0 g of 2-naphthalenethiol, 2-bromonaphthalene 5 .2 g was charged and stirred to obtain a homogeneous solution. Thereafter, 5.6 g of potassium t-butoxide and 288 mg of tetrakis (triphenylphosphine) palladium were added, and the mixture was reacted for 3 hours under a nitrogen stream while being heated to reflux. Thereafter, n-butanol was distilled off under reduced pressure, the reaction product was redissolved in 350 ml of toluene, and the insoluble matter was filtered off. Thereafter, the organic layer was washed with 100 ml of water, and then the toluene layer was dried over anhydrous magnesium sulfate. Thereafter, anhydrous magnesium sulfate was filtered off, and then toluene was distilled off to obtain a crude product. Then, after dissolving the crude product in 250 ml of toluene, the solution is dropped into 750 ml of methanol for recrystallization, filtered, and vacuum-dried to obtain 7.1 g of di (2-naphthyl) sulfide as a white solid. Got as.

  Next, 7.1 g of di (2-naphthyl) sulfide was dissolved in 240 ml of chloroform in a three-necked flask equipped with a dropping funnel and a thermometer, and this solution was cooled to 0 ° C. with an ice-saturated saline bath. After that, a solution prepared by dissolving 5.7 g of m-chloroperbenzoic acid (purity 70% by weight) containing water in 240 ml of chloroform was added dropwise over 20 minutes. Then, after making it react at the same temperature for 1 hour, the reaction solution was washed twice with 100 ml of saturated sodium hydrogensulfite aqueous solution, and further washed with 100 ml of 10 wt% potassium carbonate aqueous solution three times. Thereafter, the reaction solution was washed 3 times with 100 ml of 5% by weight oxalic acid aqueous solution, and further washed once with 100 ml of saturated saline and dried over anhydrous magnesium sulfate. Thereafter, anhydrous magnesium sulfate is filtered off, chloroform is distilled off, and then vacuum drying is performed, whereby a mixture of di (2-naphthyl) sulfoxide as a main product and di (2-naphthyl) sulfone as a by-product. Was obtained as a brown solid.

  Next, 4.5 g of the obtained mixture was dissolved in 30 ml of dichloromethane in a 200 ml eggplant flask with a nitrogen purge, and this solution was cooled to −78 ° C. with a dry ice-acetone bath. 37 ml was injected with a syringe. Then, it was made to react at reaction temperature-50 degreeC for 1 hour. Thereafter, the reaction solution was re-cooled to −78 ° C., and a tetrahydrofuran solution of 2-naphthylmagnesium bromide prepared from 792 mg of magnesium, 6.21 g of 2-bromonaphthalene and 55 ml of tetrahydrofuran was added dropwise over 10 minutes. Then, after reacting at a reaction temperature of −50 ° C. for 1 hour, the reaction solution was dropped into 100 ml of 10 wt% hydrobromic acid. Thereafter, tetrahydrofuran was distilled off from the aqueous layer under reduced pressure, the aqueous layer was extracted three times with 30 ml of chloroform, and then the organic layer was washed twice with 30 ml of water. Then, after drying an organic layer with anhydrous magnesium sulfate, magnesium sulfate was separated by filtration and the solvent was distilled off under reduced pressure. Thereafter, the amorphous solid is dissolved in 100 ml of chloroform, and then the solution is dropped into 300 ml of ethyl acetate for recrystallization, filtered, and vacuum-dried to obtain 3.3 g of tri (2-naphthyl) sulfonium bromide. Obtained as a white solid.

  Next, 1.0 g of the obtained tri (2-naphthyl) sulfonium bromide was charged into a mixed solution of 5 ml of ethyl acetate and 5 ml of distilled water, and prepared in advance from nonafluoro-n-butanesulfonic acid and aqueous ammonia. A 30% by weight aqueous ammonium nonafluoro-n-butanesulfonate solution (3.0 g) was added dropwise. Thereafter, the reaction solution was vigorously stirred for 12 hours to be reacted. Then, 30 ml of ethyl acetate was added and washed 10 times with 15 ml of distilled water. Thereafter, the solvent was distilled off from the organic layer under reduced pressure, and the obtained solid was vacuum-dried to obtain 1.3 g of tri (2-naphthyl) sulfonium nonafluoro-n-butanesulfonate as an amorphous solid. This compound is referred to as “sulfonium compound (1-1)”.

Example 2
1.0 g of tri (2-naphthyl) sulfonium bromide obtained in the same manner as in the case of tri (2-naphthyl) sulfonium bromide for the synthesis of the sulfonium compound (1-1), 5 ml of ethyl acetate and 5 distilled water The mixture was poured into a mixed solution of milliliter, and 1.5 g of a 30 wt% ammonium trifluoromethanesulfonate aqueous solution prepared beforehand from trifluoromethanesulfonic acid and ammonia was added dropwise. Thereafter, the reaction solution was reacted vigorously for 12 hours. Thereafter, 30 ml of ethyl acetate was added and washed 10 times with 15 ml of distilled water. Thereafter, the solvent was distilled off from the organic layer under reduced pressure, and the resulting solid was vacuum-dried to obtain 1.1 g of tri (2-naphthyl) sulfonium trifluoromethanesulfonate as a white solid. This compound is referred to as “sulfonium compound (1-2)”.

The sulfonium compound (1-1) and the sulfonium compound (1-2) were subjected to fast atom bombardment-mass spectrometry (FAB-MS) and ¹ H-NMR analysis under the following conditions, and were as follows.
Conditions for FAB-MS Analysis was performed under the following conditions using a “JMS-AX505W mass spectrometer” manufactured by JEOL.

Emitter current: 5 mA (used gas: Xe)
Acceleration voltage: 3.0 kV
10N MULTI: 1.3
Ionization method: Fast atom bombardment method (FAB)
Detection ion: Cation (+)
Measurement mass range: 20 to 1,500 m / z
Scanning: 30 seconds Resolution: 1,500
Matrix: 3-nitrobenzyl alcohol
¹ H-NMR Conditions Using “JNM-EX270” manufactured by JEOL Ltd., the measurement solvent was deuterated chloroform and analyzed.
-Sulphonium compound (1-1)-
FAB-MS: M / Z = 413.

¹ H-NMR: 8.57 (3H, singlet), 8.11 to 7.90 (9H, multiplet),
7.73-7.59 (9H, multiplet).
-Sulphonium compound (1-2)-
FAB-MS: M / Z = 413.

¹ H-NMR: 8.57 (3H, singlet), 8.11 to 7.90 (9H, multiplet),
7.73-7.59 (9H, multiplet).

Evaluation Example 1 (Measurement of molar extinction coefficient)
Prepared by dissolving sulfonium compound (1-1), sulfonium compound (1-2) or bis (1-naphthyl) -2-naphthylsulfonium trifluoromethanesulfonate (hereinafter referred to as “sulfonium compound (2)”) in acetonitrile. The absorption spectrum of the solution having a concentration of 1.0 × 10 ⁻⁴ mmol / liter was measured using an ultraviolet-visible spectrophotometer (V550 manufactured by JASCO Corporation) using a quartz cell with an exposure length of 10 mm. . Subsequently, the molar extinction coefficient of each sulfonium compound at a wavelength of 248 nm was calculated from the obtained absorption spectrum. The results are shown in Table 1.

Evaluation Example 2 (Performance Evaluation of Radiation Sensitive Resin Composition)
After mixing each component shown in Table 2 (positive type radiation sensitive resin composition) or Table 4 (negative type radiation sensitive resin composition) to make a uniform solution, it was filtered with a membrane filter having a pore size of 0.2 μm. A composition solution was prepared. Thereafter, each composition solution was spin-coated on a silicon wafer, and then PB was performed at 110 ° C. for 90 seconds to form a resist film having a thickness of 0.5 μm. Next, using a stepper NSR2205EX12B (numerical aperture: 0.55) manufactured by Nikon Corporation, the KrF excimer laser was exposed while changing the exposure amount, and then subjected to PEB at 110 ° C. for 90 seconds. Then, using a 2.38 wt% tetramethylammonium hydroxide aqueous solution, developing at 23 ° C. for 1 minute by the paddle method, washing with pure water and drying to form a resist pattern, the following procedure is performed. Performance evaluation was performed. The evaluation results are shown in Table 3 (positive radiation sensitive resin composition) and Table 5 (negative radiation sensitive resin composition).

sensitivity:
When the resist film formed on the silicon wafer is exposed to light and immediately subjected to PEB to form a resist pattern, a line-and-space pattern (1L1S) having a line width of 0.18 μm is formed in a one-to-one line width. The radiation dose to be used was the optimum exposure dose, and this optimum exposure dose was taken as the sensitivity.
Pattern shape:
When the upper side dimension of the line-and-space pattern (1L1S) with a design line width of 0.18 μm at the optimum exposure dose is A and the lower side dimension is B, those with 1.2 ≧ A / B ≧ 0.85 are “good” “A / B <0.85” was designated as “forward taper”, and A / B> 1.2 was designated as “reverse taper”.
Standing wave effect:
The cross-sectional shape of a line and space pattern (1L1S) having a design line width of 0.18 μm at the optimum exposure dose was observed with a scanning electron microscope to evaluate the presence or absence of the standing wave effect.
Storage stability:
The sensitivity immediately after the preparation of each composition solution and the sensitivity when stored at 20 ° C. for up to 3 months were measured and judged according to the following criteria.
○: The sensitivity change after storage for 3 months is less than 3% of the sensitivity immediately after preparation. ×: The sensitivity change after storage for 3 months is 3% or more of the sensitivity immediately after preparation.

In Tables 2 and 4, the acid generator (1), other acid generators, acid-dissociable group-containing resins, alkali-soluble resins, crosslinking agents, acid diffusion control agents, and solvents are as follows.
Acid generator (1)
A-1: Acid generator composed of sulfonium compound (1-1) A-2: Acid generator composed of sulfonium compound (1-2) Other acid generator a-1: Triphenylsulfonium trifluoromethanesulfonate a-2 : N- (10-camphorsulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide a-3: N- (trifluoromethanesulfonyloxy) bicyclo [2.2.1 ] Hept-5-ene-2,3-dicarboximide

Acid-dissociable group-containing resin B-1: p-hydroxystyrene / styrene / pt-butoxystyrene copolymer (copolymer molar ratio = 72: 5: 23, Mw = 16,000, Mw / Mn = 1 .7)
B-2: p-hydroxystyrene / p- (1-ethoxy-ethoxy) styrene / pt-butylstyrene copolymer (copolymerization molar ratio = 67: 23: 10, Mw = 13,000, Mw / Mn = 1.01)
Alkali-soluble resin C-1: p-hydroxystyrene / styrene copolymer (copolymerization molar ratio = 75: 25, Mw = 5,200, Mw / Mn = 1.52)
C-2: p-hydroxystyrene / styrene copolymer (copolymerization molar ratio = 85: 15, Mw = 5,600, Mw / Mn = 1.50)

Crosslinking agent D-1: N, N ′, N ^″ , N ^{′ ″} -tetra (methoxymethyl) glycoluric acid diffusion controller E-1: 2-phenylbenzimidazole E-2: N- (t-butoxy Carbonyl) -2-phenylbenzimidazole solvent S-1: Ethyl lactate S-2: Ethyl 3-ethoxypropionate S-3: Propylene glycol monomethyl ether acetate

Claims (10)

A sulfonium compound represented by the following general formula (1).

[In the general formula (1), R ¹ represents a substituted or unsubstituted monovalent aromatic hydrocarbon group having 6 to 20 carbon atoms, and R ² and R ³ are each independently a straight chain having 1 to 14 carbon atoms. A linear or branched alkyl group, a monovalent alicyclic hydrocarbon group having 3 to 14 carbon atoms, a linear or branched alkoxyl group having 1 to 14 carbon atoms, an —OR ⁴ group (provided that
R ⁴ represents a C 3-14 monovalent hydrocarbon group having an alicyclic ring. ), A linear or branched alkylsulfanyl group having 1 to 14 carbon atoms, an organic sulfanyl group having 3 to 14 carbon atoms having an alicyclic ring, and a linear or branched alkylsulfonyl group having 1 to 14 carbon atoms. Or an organic sulfonyl group having 3 to 14 carbon atoms having an alicyclic ring, p and q are each an integer of 0 to 6, and X ⁻ is a monovalent organic acid anion having 1 to 20 carbon atoms or OH ⁻ is shown. ] The sulfonium compound according to claim 1, wherein R ¹ in the general formula (1) is a group represented by the following general formula (2).

[In the general formula (2), R ⁵ represents a linear or branched alkyl group having 1 to 14 carbon atoms, a monovalent alicyclic hydrocarbon group having 3 to 14 carbon atoms, and a straight chain having 1 to 14 carbon atoms. A linear or branched alkoxyl group, —OR ⁴ group (where R ⁴ represents a monovalent hydrocarbon group having 3 to 14 carbon atoms having an alicyclic ring), linear chain having 1 to 14 carbon atoms Or branched alkylsulfanyl group, organic sulfanyl group having 3 to 14 carbon atoms having an alicyclic ring, linear or branched alkylsulfonyl group having 1 to 14 carbon atoms, or carbon having an alicyclic ring The organic sulfonyl group of number 3-14 is shown, r is an integer of 0-6. ] The sulfonium compound according to claim 1, wherein R ¹ in the general formula (1) is a group represented by the following general formula (3).

[In General Formula (3), R ⁵ represents a linear or branched alkyl group having 1 to 14 carbon atoms, a monovalent alicyclic hydrocarbon group having 3 to 14 carbon atoms, and a straight chain having 1 to 14 carbon atoms. A linear or branched alkoxyl group, —OR ⁴ group (where R ⁴ represents a monovalent hydrocarbon group having 3 to 14 carbon atoms having an alicyclic ring), linear chain having 1 to 14 carbon atoms Or branched alkylsulfanyl group, organic sulfanyl group having 3 to 14 carbon atoms having an alicyclic ring, linear or branched alkylsulfonyl group having 1 to 14 carbon atoms, or carbon having an alicyclic ring The organic sulfonyl group of number 3-14 is shown, r is an integer of 0-6. ]   The sulfonium compound according to claim 2, wherein p and q in the general formula (1) and r in the general formula (2) are 0.   The sulfonium compound according to claim 3, wherein p and q in the general formula (1) and r in the general formula (3) are 0. X in the general formula (1) ^- sulfonium compound according to any one of claims 1 to 5 is a monovalent organic acid anion having 2 to 20 carbon atoms. The sulfonium compound according to claim 6, wherein X ^- is a monovalent sulfonate anion having 2 to 20 carbon atoms.   The radiation sensitive acid generator which consists of a sulfonium compound in any one of Claims 1-7.   (A) a radiation-sensitive acid generator comprising the radiation-sensitive acid generator of claim 8 as an essential component; and (B) an alkali-insoluble or hardly soluble resin having an acid-dissociable group, A positive radiation-sensitive composition comprising a resin that becomes readily soluble in alkali when a group is dissociated.   (A) A radiation-sensitive acid generator comprising the radiation-sensitive acid generator of claim 8 as an essential component; (C) an alkali which is crosslinked by a crosslinking agent in the presence of an acid (D) and becomes hardly soluble or insoluble in alkali. A negative radiation-sensitive resin composition comprising a soluble resin and (D) a crosslinking agent.