JP5564555B2 - NOVEL COMPOUND AND PROCESS FOR PRODUCING THE SAME, ACID GENERATOR, RESIST COMPOSITION AND METHOD FOR FORMING RESIST PATTERN - Google Patents

Description

  The present invention relates to a novel compound useful as an acid generator for a resist composition and a method for producing the same, a compound useful as a precursor of the compound, an acid generator, a resist composition, and a method for forming a resist pattern.

In lithography technology, for example, a resist film made of a resist material is formed on a substrate, and the resist film is selectively exposed to light such as light or an electron beam through a mask on which a predetermined pattern is formed. And a development process is performed to form a resist pattern having a predetermined shape on the resist film. A resist material in which the exposed portion changes to a property that dissolves in the developer is referred to as a positive type, and a resist material that changes to a property in which the exposed portion does not dissolve in the developer is referred to as a negative type.
In recent years, in the manufacture of semiconductor elements and liquid crystal display elements, pattern miniaturization has been rapidly progressing due to advances in lithography technology.
As a technique for miniaturization, the wavelength of an exposure light source is generally shortened. Specifically, conventionally, ultraviolet rays typified by g-line and i-line have been used. Currently, mass production of semiconductor elements using a KrF excimer laser or an ArF excimer laser has been started. In addition, studies have been made on F ₂ excimer lasers, electron beams, EUV (extreme ultraviolet rays), X-rays, and the like having shorter wavelengths than these excimer lasers.

  Resist materials are required to have lithography characteristics such as sensitivity to these exposure light sources and resolution capable of reproducing a pattern with fine dimensions. As a resist material that satisfies such requirements, a chemically amplified resist containing a base resin whose solubility in an alkaline developer is changed by the action of an acid and an acid generator that generates an acid upon exposure is used. For example, a positive chemically amplified resist contains, as a base resin, a resin that increases solubility in an alkaline developer by the action of an acid and an acid generator. When the acid is generated, the exposed portion becomes soluble in the alkaline developer.

Up to now, as the base resin for chemically amplified resist, polyhydroxystyrene (PHS), which is highly transparent to KrF excimer laser (248 nm), and a resin whose hydroxyl group is protected with an acid dissociable, dissolution inhibiting group (PHS resin) Has been used. However, since the PHS resin has an aromatic ring such as a benzene ring, the transparency to light having a wavelength shorter than 248 nm, for example, 193 nm, is not sufficient. For this reason, a chemically amplified resist having a PHS resin as a base resin component has drawbacks such as low resolution in a process using 193 nm light, for example. Therefore, as a resist base resin currently used in ArF excimer laser lithography and the like, it has a structural unit generally derived from a (meth) acrylic acid ester in the main chain because it is excellent in transparency near 193 nm. Resin (acrylic resin) is used. In the case of the positive type, such a resin includes a structural unit derived from a (meth) acrylic acid ester containing a tertiary alkyl ester type acid dissociable, dissolution inhibiting group containing an aliphatic polycyclic group, for example, 2-alkyl. A resin having a structural unit derived from 2-adamantyl (meth) acrylate or the like is mainly used (for example, see Patent Document 1).
The “(meth) acrylic acid ester” means one or both of an acrylic acid ester having a hydrogen atom bonded to the α-position and a methacrylic acid ester having a methyl group bonded to the α-position. “(Meth) acrylate” means one or both of an acrylate having a hydrogen atom bonded to the α-position and a methacrylate having a methyl group bonded to the α-position. “(Meth) acrylic acid” means one or both of acrylic acid having a hydrogen atom bonded to the α-position and methacrylic acid having a methyl group bonded to the α-position.

  Various types of acid generators used in chemically amplified resists have been proposed so far, and for example, onium salt-based acid generators such as iodonium salts and sulfonium salts are known.

JP 2003-241385 A

Currently, perfluoroalkylsulfonic acid ions are generally used as the anion portion of the onium salt acid generator as described above. It is considered that a longer perfluoroalkyl chain of such an anion is preferable in order to suppress acid diffusion after exposure. However, perfluoroalkyl chains having 6 to 10 carbon atoms are hardly decomposable, and nonafluorobutanesulfonic acid ions or the like are used for the safety of handling in consideration of bioaccumulation. Therefore, there is a demand for a novel compound that is more suitable as an acid generator for resist compositions.
The present invention has been made in view of the above circumstances, and is a novel compound useful as an acid generator for a resist composition, a method for producing the same, a compound useful as a precursor of the compound, an acid generator, and a resist. It is an object to provide a composition and a method for forming a resist pattern.

In order to achieve the above object, the present invention employs the following configuration.
That is, the 1st aspect of this invention is a compound (henceforth a compound (B1)) represented by the following general formula (b1-1).

［式中、Ｒ^１は置換基を有していてもよいアリール基またはアルキル基であり、Ｒ^３は水素原子またはアルキル基であり、ｎ１は０または１であり、ｎ１が１である場合、Ｒ^１及びＲ^３は相互に結合して、当該Ｒ^１が結合した炭素原子およびＲ^３が結合した炭素原子とともに３〜７員環構造の環を形成してもよく、Ａは、当該Ａが結合した硫黄原子とともに３〜７員環構造の環を形成する２価の基であり、前記環は置換基を有していてもよく、Ｒ^２はＲ^５３−Ｒ^５４−（式中、Ｒ^５３は炭素数２〜１０のアルケニル基またはアリール基であり、Ｒ^５４は炭素数１〜５の直鎖状または分岐鎖状のアルキレン基である。）で表される基であり、ｎは０であり、Ｙ^１はフッ素置換されていてもよい炭素数１〜４のアルキレン基である。］

[Wherein, R ¹ is an aryl group or an alkyl group which may have a substituent, R ³ is a hydrogen atom or an alkyl group, n1 is 0 or 1, and n1 is 1, R ¹ and R ³ may be bonded to each other to form a ^3- to 7-membered ring with the carbon atom to which R ¹ is bonded and the carbon atom to which R ³ is bonded; It is a divalent group that forms a ring having a 3- to 7-membered ring structure with a bonded sulfur atom, and the ring may have a substituent, and R ² represents R ⁵³ —R ⁵⁴ — (wherein R ⁵³ is an alkenyl group or aryl group having 2 to 10 carbon atoms, R ⁵⁴ is a linear or branched alkylene group having 1 to 5 carbon atoms, and n is 0 Y ¹ is an optionally substituted alkylene group having 1 to 4 carbon atoms. ]

  In a second aspect of the present invention, a compound represented by the following general formula (I), a compound represented by the following general formula (II), and a copper catalyst are reacted to form the following general formula (b1-1-1). It is a manufacturing method (henceforth the manufacturing method of a compound (B1-1)) of the compound represented by general formula (b1-1-1) including the process of obtaining the compound represented by 1).

［式中、Ａは、当該Ａが結合した硫黄原子とともに３〜７員環構造の環を形成する２価の基であり、前記環は置換基を有していてもよく、Ｒ^２はＲ^５３−Ｒ^５４−（式中、Ｒ^５３は炭素数２〜１０のアルケニル基またはアリール基であり、Ｒ^５４は炭素数１〜５の直鎖状または分岐鎖状のアルキレン基である。）で表される基であり、ｎは０であり、Ｙ^１はフッ素置換されていてもよい炭素数１〜４のアルキレン基であり、Ｒ^１は、それぞれ独立に、置換基を有していてもよいアリール基またはアルキル基である。］

[Wherein, A is a divalent group that forms a ring with a 3- to 7-membered ring structure together with the sulfur atom to which A is bonded, and the ring may have a substituent, and R ² represents R ⁵³ —R ⁵⁴ — (wherein R ⁵³ is an alkenyl group or aryl group having 2 to 10 carbon atoms, and R ⁵⁴ is a linear or branched alkylene group having 1 to 5 carbon atoms). A group represented by the formula, n is 0, Y ¹ is an optionally substituted alkylene group having 1 to 4 carbon atoms, and each R ¹ independently has a substituent. A good aryl or alkyl group. ]

  A third aspect of the present invention is a compound represented by the following general formula (I) (hereinafter referred to as compound (I)).

［式中、Ｒ^２はＲ^５３−Ｒ^５４−（式中、Ｒ^５３は炭素数２〜１０のアルケニル基またはアリール基であり、Ｒ^５４は炭素数１〜５の直鎖状または分岐鎖状のアルキレン基である。）で表される基であり、ｎは０であり、Ｙ^１はフッ素置換されていてもよい炭素数１〜４のアルキレン基であり、Ｒ^１は、それぞれ独立に、置換基を有していてもよいアリール基またはアルキル基である。］

[Wherein R ² is R ⁵³ —R ⁵⁴ — (wherein R ⁵³ is an alkenyl group or aryl group having 2 to 10 carbon atoms, and R ⁵⁴ is a linear or branched chain having 1 to 5 carbon atoms. And n 1 is 0, Y ¹ is an optionally substituted alkylene group having 1 to 4 carbon atoms, and each R ¹ is independently An aryl group or an alkyl group which may have a substituent. ]

  The fifth aspect of the present invention is an acid generator comprising the compound (B1) of the first aspect.

A sixth aspect of the present invention is a resist composition containing a base component (A) whose solubility in an alkaline developer is changed by the action of an acid, and an acid generator component (B) that generates an acid upon exposure. There,
The acid generator component (B) is a resist composition containing an acid generator (B1) composed of a compound represented by the following general formula (b1-1).

［式中、Ｒ^１は置換基を有していてもよいアリール基またはアルキル基であり、Ｒ^３は水素原子またはアルキル基であり、ｎ１は０または１であり、ｎ１が１である場合、Ｒ^１及びＲ^３は相互に結合して、当該Ｒ^１が結合した炭素原子およびＲ^３が結合した炭素原子とともに３〜７員環構造の環を形成してもよく、Ａは、当該Ａが結合した硫黄原子とともに３〜７員環構造の環を形成する２価の基であり、前記環は置換基を有していてもよく、Ｒ^２はＲ^５３−Ｒ^５４−（式中、Ｒ^５３は炭素数２〜１０のアルケニル基またはアリール基であり、Ｒ^５４は炭素数１〜５の直鎖状または分岐鎖状のアルキレン基である。）で表される基であり、ｎは０であり、Ｙ^１はフッ素置換されていてもよい炭素数１〜４のアルキレン基である。］

[Wherein, R ¹ is an aryl group or an alkyl group which may have a substituent, R ³ is a hydrogen atom or an alkyl group, n1 is 0 or 1, and n1 is 1, R ¹ and R ³ may be bonded to each other to form a ^3- to 7-membered ring with the carbon atom to which R ¹ is bonded and the carbon atom to which R ³ is bonded; It is a divalent group that forms a ring having a 3- to 7-membered ring structure with a bonded sulfur atom, and the ring may have a substituent, and R ² represents R ⁵³ —R ⁵⁴ — (wherein R ⁵³ is an alkenyl group or aryl group having 2 to 10 carbon atoms, R ⁵⁴ is a linear or branched alkylene group having 1 to 5 carbon atoms, and n is 0 Y ¹ is an optionally substituted alkylene group having 1 to 4 carbon atoms. ]

  According to a seventh aspect of the present invention, there is provided a step of forming a resist film on a support using the resist composition of the sixth aspect, a step of exposing the resist film, and an alkali development of the resist film to develop a resist It is a resist pattern formation method including the process of forming a pattern.

In this description and in the claims,
“Aliphatic” is a relative concept with respect to aromatics, and is defined to mean groups, compounds, etc. that do not have aromaticity.
Unless otherwise specified, the “alkyl group” includes linear, branched and cyclic monovalent saturated hydrocarbon groups.
Unless otherwise specified, the “alkylene group” includes linear, branched and cyclic divalent saturated hydrocarbon groups.
The “lower alkyl group” is an alkyl group having 1 to 5 carbon atoms.
“Structural unit” means a monomer unit (monomer unit) constituting a resin component (polymer).
“Exposure” is a concept that includes general irradiation of radiation.

  ADVANTAGE OF THE INVENTION According to this invention, the novel compound useful as an acid generator for resist compositions, its manufacturing method, a compound useful as a precursor of this compound, an acid generator, a resist composition, and a resist pattern formation method can be provided. .

<< Compound (B1) >>
The compound (B1) of the first aspect of the present invention is represented by the general formula (b1-1).
In formula (b1-1), n1 is 0 or 1. When n1 is 0, the compound (B1) is represented by the following general formula (b1-1-1). When n1 is 1, the compound (B1) is represented by the following general formula (b1-1-2).

［式中、Ｒ^１、Ｒ^３、Ａ、Ｒ^２、ｎ、Ｙ^１はそれぞれ式（ｂ１−１）中のＲ^１、Ｒ^３、Ａ、Ｒ^２、ｎ、Ｙ^１と同じである。］

^{Wherein, R 1, R 3, A} , R 2, n, Y 1 is ^R 1, respectively formula (b1-1) ^{in, R 3, A, R 2} , n, and ^{Y 1} same. ]

The aryl group of R ^1, is not particularly limited, for example, an aryl group having 6 to 20 carbon atoms. The aryl group is preferably an aryl group having 6 to 10 carbon atoms because it can be synthesized at low cost, and specific examples include a phenyl group and a naphthyl group.
The aryl group may have a substituent. Here, the aryl group having a substituent means that part or all of the hydrogen atoms of the unsubstituted aryl group are substituted with a substituent (a group or atom other than a hydrogen atom).
Examples of the substituent that the aryl group may have include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, and a hydroxyl group.
The alkyl group as a substituent of the aryl group is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.
The alkoxy group as a substituent for the aryl group is preferably an alkoxy group having 1 to 5 carbon atoms, and examples thereof include a methoxy group, an ethoxy group, a propoxy group, an n-butoxy group, and a tert-butoxy group.
The alkoxy group as the substituent of the aryl group is preferably an alkoxy group having 1 to 5 carbon atoms, and includes a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, and a tert-butoxy group. A methoxy group and an ethoxy group are preferable.
Examples of the halogen atom as the substituent for the aryl group include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
Examples of the halogenated alkyl group as a substituent for the aryl group include groups in which some or all of the hydrogen atoms of the alkyl group have been substituted with the halogen atoms.

The alkyl group of R ^1, is not particularly limited, for example, linear C1-10, branched or cyclic alkyl group, and the like. It is preferable that it is C1-C5 from the point which is excellent in resolution. Specific examples include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an n-pentyl group, a cyclopentyl group, a hexyl group, a cyclohexyl group, a nonyl group, and a decanyl group. . A methyl group is preferable because it is excellent in resolution and can be synthesized at low cost.
The alkyl group may have a substituent. Here, the alkyl group having a substituent means that part or all of the hydrogen atoms of the unsubstituted alkyl group are substituted with a substituent (a group or atom other than a hydrogen atom).
Examples of the substituent that the alkyl group may have include an alkoxy group, a halogen atom, and a hydroxyl group. Examples of the alkoxy group and the halogen atom include the same alkoxy groups and halogen atoms as the substituents that the aryl group may have.

In the present invention, R ¹ is preferably an aryl group which may have a substituent, more preferably a phenyl group or naphthyl group which may have a substituent, and R ^{1 which} has a substituent. A good phenyl group is most preferred.

The alkyl group of R ^3, is not particularly limited, the same as the alkyl group of said R ^1.
In the present invention, R ³ is preferably a hydrogen atom or a methyl group, and more preferably a hydrogen atom.

When n1 is 1, R ¹ and R ³ in the formula are bonded to each other to form a ^3- to 7-membered ring together with the carbon atom to which R ¹ is bonded and the carbon atom to which R ³ is bonded. May be. The ring is preferably a 5- to 7-membered ring structure, and more preferably a 5- or 6-membered ring structure.

A is a divalent group that forms a 3- to 7-membered ring structure together with the sulfur atom to which A is bonded, and the ring may have a substituent.
In A, the ring preferably has a 5- to 7-membered ring structure, and more preferably a 5- or 6-membered ring structure.
Examples of the substituent that the ring may have include the same substituents as those described as the substituent that the aryl group of R ¹ may have.

  As the cation moiety of the compound (B1), a cation moiety represented by general formula (b1'-1) or (b1'-2) shown below is particularly desirable.

In the formula, R ⁸ and R ⁹ are each independently a phenyl group, a naphthyl group, or an alkyl group having 1 to 5 carbon atoms, which may have a substituent. As the alkyl group, a methyl group is particularly preferable.
a is an integer of 1 to 3, and 1 or 2 is most preferable.

In the formula (b1-1), the aromatic group represented by R ² may be a hydrocarbon group composed of only a carbon atom and a hydrogen atom, and includes a hetero atom including a carbon atom, a hydrogen atom and other heteroatoms. It may be an atom-containing group. Specifically, an aryl group obtained by removing one hydrogen atom from an aromatic hydrocarbon ring such as a phenyl group, a biphenyl group, a fluorenyl group, a naphthyl group, an anthryl group, or a phenanthryl group A heteroaryl group in which a part of carbon atoms constituting the ring of these aryl groups is substituted with a heteroatom such as an oxygen atom, a sulfur atom or a nitrogen atom; a benzyl group, a phenethyl group, a 1-naphthylmethyl group, 2- Examples thereof include arylalkyl groups such as naphthylmethyl group, 1-naphthylethyl group, and 2-naphthylethyl group.
The number of carbon atoms in the alkyl chain in the arylalkyl group is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.
The aromatic group of R ² may have a substituent. Examples of the substituent include the same as those described as the substituent that the aryl group of R ¹ may have.

In R ² , examples of the linear alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, and a decanyl group. Etc. Among these, a methyl group is preferable.
Examples of the branched alkyl group having 1 to 10 carbon atoms include 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, Examples include 1-ethylbutyl group, 2-ethylbutyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group and the like.
The alkyl group of R ² may have a substituent. Examples of the substituent include the same groups as those described above as the substituent that the alkyl group of R ¹ may have.

The linear or branched alkenyl group having 2 to 10 carbon atoms of R ² preferably has 2 to 5 carbon atoms, more preferably 2 to 4 carbon atoms, and particularly preferably 3. Specific examples include a vinyl group, a propenyl group (allyl group), a butynyl group, a 1-methylpropenyl group, and a 2-methylpropenyl group, and a propenyl group is particularly preferable.
The alkenyl group for R ² may have a substituent. Examples of the substituent include the same groups as those described above as the substituent that the alkyl group of R ¹ may have.

Here, in R ² , “may have a substituent” means that in the aromatic hydrocarbon group, a linear or branched alkyl group, or a linear or branched alkenyl group. This means that part or all of the hydrogen atoms may be substituted with a substituent (an atom or group other than a hydrogen atom).
The number of substituents in R ² may be one or two or more.

  n may be 0 or 1.

Y ¹ is an alkylene group having 1 to 4 carbon atoms and optionally substituted by fluorine.
Examples of the alkylene group having 1 to 4 carbon atoms which may be fluorine-substituted for Y ¹ include —CF ₂ —, —CF ₂ CF ₂ —, —CF ₂ CF ₂ CF ₂ —, and —CF (CF ₃ ) CF. _{2 -, - CF (CF 2} CF 3) -, - C (CF 3) 2 -, - CF 2 CF 2 CF 2 CF 2 -, - CF (CF 3) CF 2 CF 2 -, - CF 2 CF ( CF ₃ ) CF ₂ —, —CF (CF ₃ ) CF (CF ₃ ) —, —C (CF ₃ ) ₂ CF ₂ —, —CF (CF ₂ CF ₃ ) CF ₂ —, —CF (CF ₂ CF _{2 CF 3) -, - C (} CF 3) (CF 2 CF 3) -; - CHF -, - CH 2 CF 2 -, - CH 2 CH 2 CF 2 -, - CH 2 CF 2 CF 2 -, - CH (CF ₃ ) CH ₂ —, —CH (CF ₂ CF ₃ ) —, —C (CH ₃ ) (CF _{3 ) -, - CH 2 CH 2} CH 2 CF 2 -, - CH 2 CH 2 CF 2 CF 2 -, - CH (CF 3) CH 2 CH 2 -, - CH 2 CH (CF 3) CH 2 -, - CH (CF ₃ ) CH (CF ₃ ) —, —C (CF ₃ ) ₂ CH ₂ —; —CH ₂ —, —CH ₂ CH ₂ —, —CH ₂ CH ₂ CH ₂ —, —CH (CH ₃ ) _{CH 2 -, - CH (CH} 2 CH 3) -, - C (CH 3) 2 -, - CH 2 CH 2 CH 2 CH 2 -, - CH (CH 3) CH 2 CH 2 -, - CH 2 CH _{(CH 3) CH 2 -,} - CH (CH 3) CH (CH 3) -, - C (CH 3) 2 CH 2 -, - CH (CH 2 CH 3) CH 2 -, - CH (CH 2 CH _{2 CH 3) -, - C} (CH 3) (CH 2 CH 3) - , and the like.

Y ¹ is preferably a fluorine-substituted alkylene group having 1 to 4 carbon atoms (fluorinated alkylene group), particularly preferably a fluorinated alkylene group in which the carbon atom bonded to the adjacent sulfur atom is fluorinated. . Examples of such fluorinated alkylene _{group, -CF 2 -, - CF 2} CF 2 -, - CF 2 CF 2 CF 2 -, - CF (CF 3) CF 2 -, - CF 2 CF 2 CF 2 CF 2 _{-, - CF (CF 3)} CF 2 CF 2 -, - CF 2 CF (CF 3) CF 2 -, - CF (CF 3) CF (CF 3) -, - C (CF 3) 2 CF 2 -, _{-CF (CF 2 CF 3) CF} 2 -; - CH 2 CF 2 -, - CH 2 CH 2 CF 2 -, - CH 2 CF 2 CF 2 -; - CH 2 CH 2 CH 2 CF 2 -, - CH ₂ CH ₂ CF ₂ CF ₂ —, —CH ₂ CF ₂ CF ₂ CF ₂ — and the like can be mentioned.
Of _{these, -CF 2 CF 2 -, -} CF 2 CF 2 CF 2 -, or _CH 2 _CF 2 CF ₂ - is preferable, _-CF 2 CF ₂ - or _-CF 2 _CF 2 CF ₂ - is more preferable, -CF ₂ CF ₂ - is particularly preferred.

  In the present invention, the anion moiety of the compound (B1) is preferably an anion moiety represented by the following general formula (b1 ″ -1).

［式中、Ｙ^１は前記と同じであり、Ｒ^５３は炭素数２〜１０のアルケニル基またはアリール基であり、Ｒ^５４は炭素数１〜５の直鎖状または分岐鎖状のアルキレン基である。］

[Wherein, Y ¹ is as defined above, R ⁵³ is an alkenyl group or aryl group having 2 to 10 carbon atoms, and R ⁵⁴ is a linear or branched alkylene group having 1 to 5 carbon atoms. is there. ]

R ⁵³ is preferably a vinyl group, a phenyl group or a naphthyl group, more preferably a vinyl group or a naphthyl group.
R ⁵⁴ is preferably a linear alkylene group having 1 to 5 carbon atoms, and most preferably a methylene group.

  As the compound (B1) of the present invention, a cation moiety represented by the general formula (b1′-1) or (b1′-2), an anion moiety represented by the general formula (b1 ″ -1), A compound consisting of

<Method for producing compound (B1)>
It does not specifically limit as a manufacturing method of the compound (B1) of this invention, The manufacturing method of a well-known sulfonium salt can be utilized.
For example, the compound (B1) is obtained by reacting the compound (b0-1) represented by the following general formula (b0-1) with the compound (b0-2) represented by the following general formula (b0-2). Can be obtained.

［式中、Ｒ^２、ｎ、Ｙ^１、Ａ、Ｒ^３、ｎ１、Ｒ^１はそれぞれ式（ｂ１−１）中のＲ^２、ｎ、Ｙ^１、Ａ、Ｒ^３、ｎ１、Ｒ^１と同じである。Ｍ^＋はアルカリ金属イオンであり、Ｘｈ⁻はハロゲンイオンである。］

^{Wherein, R 2, n, Y 1} , A, R 3, n1, R 1 is ^{R 2,} n, respectively formula (b1-1) ^in, Y ^1, A, the same as ^R 3, n1, R ¹ It is. M ⁺ is an alkali metal ion, and Xh ⁻ is a halogen ion. ]

Examples of the alkali metal ion of M ⁺ include sodium ion, lithium ion, potassium ion and the like, and sodium ion or lithium ion is preferable.
Xh ^- The halogen ion, a chlorine ion, a bromine ion, and iodine ion, etc., chlorine ions or bromine ions are preferred.
Compound (b0-1) and compound (b0-2) can be reacted, for example, by bringing these compounds into contact with each other in a solvent such as water or dichloromethane.

  Although the manufacturing method of compound (b0-1) is not specifically limited, For example, the compound represented by the following general formula (b0-1-11) is made into sodium hydroxide, lithium hydroxide, etc. in solvent, such as tetrahydrofuran and water. To give a compound represented by the following general formula (b0-1-12) in an aqueous solution of an alkali metal hydroxide, and then the compound is converted into an acidic catalyst in an organic solvent such as benzene or dichloroethane. In the presence, by dehydration condensation with an alcohol represented by the following general formula (b0-1-13), a compound in which n in the general formula (b0-1) is 1 (the following general formula (b0-1) −01)) is obtained.

［式中、Ｒ^２１は炭素数１〜５のアルキル基であり、Ｙ^１、Ｍ^＋、Ｒ^２はそれぞれ式（ｂ０−１）中のＹ^１、Ｍ^＋、Ｒ^２と同じであり、Ｘｈ⁻は式（ｂ０−２）中のＸｈ⁻と同じである。］

^{Wherein, R 21} is an alkyl group of 1 to 5 carbon ^{atoms, Y 1, M +, R} 2 is ^Y 1, respectively formula (b0-1) ^in, M +, are the same as ^{R 2,} Xh ^- is Xh in the formula (b0-2) ^- is the same as that. ]

  In addition, for example, fluorine silver, a compound represented by the following general formula (b0-1-01), and a compound represented by the following general formula (b0-1-02) in an organic solvent such as anhydrous diglyme To obtain a compound represented by the following general formula (b0-1-03), and the compound in an organic solvent such as tetrahydrofuran, acetone or methyl ethyl ketone, and an alkali such as sodium hydroxide or lithium hydroxide. By reacting with a metal hydroxide, a compound in which n in the general formula (b0-1) is 0 (a compound represented by the following general formula (b0-1-0)) is obtained.

［式中、Ｙ^１、Ｍ^＋、Ｒ^２はそれぞれ式（ｂ０−１）中のＹ^１、Ｍ^＋、Ｒ^２と同じであり、Ｘｈ⁻は式（ｂ０−２）中のＸｈ⁻と同じである。］

^{Wherein, Y 1, M +, R} 2 is ^{Y 1,} M +, respectively formula (b0-1) in the same as ^{R 2,} Xh ^- Xh in the formula (b0-2) is ^- the same It is. ]

Although the manufacturing method of compound (b0-2) is not specifically limited, For example,-[CH (R < ³ >)-> is made into the sulfur atom of the compound represented by the following general formula (b0-2-1) by a well-known method. _CO] can be obtained by introducing a group represented by n1 -R ^1.
As a specific example, for example, in the case where n1 is 0, a compound represented by the following general formula (b0-2-1) is oxidized to convert -S- moiety in the compound to -S (= O) −, and by reacting this with an aromatic hydrocarbon such as benzene or an alkane such as methane in the presence of a catalyst such as aluminum chloride, n1 in the general formula (b0-2) is 0. Is obtained. When n1 is 1, you may obtain and use a commercially available bromide body etc., for example.

［式中、Ａは前記と同じである。］

[Wherein, A is the same as defined above. ]

  When n1 is 0, that is, when the compound (B1) is a compound represented by the general formula (b-1-1) (hereinafter sometimes referred to as the compound (B1-1)), the compound As a method for producing (B1-1), a method for producing the compound (B1-1) of the present invention described later is suitable.

<< Method for Producing Compound (B1-1) >>
The production method of the compound (B1-1) of the second aspect of the present invention (hereinafter referred to as production method (1)) is referred to as a compound represented by the following general formula (I) (hereinafter referred to as compound (I)). ), A compound represented by the following general formula (II) (hereinafter referred to as compound (II)), and a copper catalyst are reacted to give a compound (B1) represented by the following general formula (b1-1-1) -1) is obtained.
By performing these steps, R ¹ in compound (I) is introduced into the sulfur atom of compound (II) to form a sulfonium ion, and the sulfonium ion and the anion moiety of compound (I) form a salt. To form compound (B1-1).

［式中、Ａは、当該Ａが結合した硫黄原子とともに３〜７員環構造の環を形成する２価の基であり、前記環は置換基を有していてもよく、Ｒ^２は置換基を有していてもよい芳香族炭化水素基、置換基を有していても良い炭素数１〜１０の直鎖状もしくは分岐状のアルキル基、または置換基を有していてもよい炭素数２〜１０の直鎖状もしくは分岐状のアルケニル基であり、ｎは０または１であり、Ｙ^１はフッ素置換されていてもよい炭素数１〜４のアルキレン基であり、Ｒ^１は、それぞれ独立に、置換基を有していてもよいアリール基またはアルキル基である。］

[Wherein, A is a divalent group that forms a 3- to 7-membered ring structure together with the sulfur atom to which A is bonded, and the ring may have a substituent, and R ² is a substituted group. An aromatic hydrocarbon group which may have a group, a linear or branched alkyl group having 1 to 10 carbon atoms which may have a substituent, or carbon which may have a substituent A linear or branched alkenyl group having 2 to 10 carbon atoms, n is 0 or 1, Y ¹ is an optionally substituted alkylene group having 1 to 4 carbon atoms, and R ¹ is Each independently represents an aryl group or an alkyl group which may have a substituent. ]

^{Wherein, A, R 2, n,} Y 1, R 1 are each independently, ^A in the general formula (b-1), R 2 , n, is the same as Y 1, ^{R 1.}

  The compound (I) used here is a novel compound. The compound (I) can be produced, for example, by the method for producing compound (I) described later.

  As compound (II), a commercially available product may be used or synthesized.

  The copper catalyst is preferably a divalent copper catalyst, and specifically includes a compound represented by the following general formula (III) (hereinafter referred to as compound (III)).

［式中、Ｒ^６は置換基を有していてもよいアリール基である。］

[Wherein, R ⁶ represents an aryl group which may have a substituent. ]

In the formula, examples of the aryl group which may have a substituent of R ⁶ include the same groups as those described as the aryl group which may have a substituent of R ¹ .
Specific examples of the compound (III) include copper (II) benzoate.
As compound (III), a commercially available product can be used.

The method of reacting compound (I), compound (II) and copper catalyst is not particularly limited. For example, compound (I), compound (II) and copper catalyst are reacted in a reaction solvent. The method of letting it be mentioned.
Any reaction solvent may be used as long as it can dissolve the raw materials, and specific examples thereof include chlorobenzene toluene.
The reaction temperature is preferably 50 to 150 ° C, more preferably 90 to 120 ° C.
The reaction time varies depending on the reactivity of compound (I) and compound (II), the reaction temperature, etc., but usually it is preferably 10 to 180 minutes, more preferably 30 to 90 minutes.
About 0.5-3 molar equivalent is preferable with respect to the usage-amount of compound (I), and, as for the usage-amount of compound (II), 0.9-1.5 molar equivalent is more preferable.
About 0.01-0.5 molar equivalent is preferable with respect to compound (I), and, as for the usage-amount of a copper catalyst, 0.02-0.1 molar equivalent is more preferable.

The structure of the compound (B1-1) obtained in the above step is as follows: ¹ H-nuclear magnetic resonance (NMR) spectrum method, ¹³ C-NMR spectrum method, ¹⁹ F-NMR spectrum method, infrared absorption (IR) spectrum method, mass It can be confirmed by a general organic analysis method such as analysis (MS) method, elemental analysis method or X-ray crystal diffraction method.

<< Compound (I) >>
The compound (I) of the third aspect of the present invention is represented by the general formula (I).
Wherein ^{(I), R 2, n} , Y 1, R 1 is ^R 2, ⁿ of each of the general formula (b1-1) in ^an Y 1, ^{R 1} same.
Compound (I) is useful as a precursor of the compound (B1-1), and is suitably used for the production method (1) of the compound (B1-1).
Compound (I) is itself usable as an acid generator, and can be blended in a resist composition as an acid generator.

<< Production Method of Compound (I) >>
The production method of compound (I) includes a compound represented by the following general formula (I-1) (hereinafter referred to as compound (I-1)) and a compound represented by the following general formula (I-2) ( Hereinafter, it includes a step of obtaining compound (I) by reacting with compound (I-2).

［式中、Ｒ^２は置換基を有していてもよい芳香族炭化水素基、置換基を有していてもよい炭素数１〜１０の直鎖状もしくは分岐状のアルキル基、または置換基を有していてもよい炭素数２〜１０の直鎖状もしくは分岐状のアルケニル基であり、ｎは０または１であり、Ｙ^１はフッ素置換されていてもよい炭素数１〜４のアルキレン基であり、Ｍ^＋はアルカリ金属イオンであり、Ｒ^１は、それぞれ独立に、置換基を有していてもよいアリール基またはアルキル基であり、Ｒ^７はアルキル基またはフッ素化アルキル基である。］

[Wherein R ² represents an aromatic hydrocarbon group which may have a substituent, a linear or branched alkyl group having 1 to 10 carbon atoms which may have a substituent, or a substituent. A linear or branched alkenyl group having 2 to 10 carbon atoms, n is 0 or 1, and Y ¹ is an optionally substituted alkylene having 1 to 4 carbon atoms. M ⁺ is an alkali metal ion, R ¹ is independently an aryl group or an alkyl group which may have a substituent, and R ⁷ is an alkyl group or a fluorinated alkyl group. . ]

^{Wherein, R 2, n, Y 1} , R 1 is ^R 2, ⁿ of each of the general formula (b1-1) in ^an Y 1, ^{R 1} same.
Examples of the M ⁺ alkali metal ion include sodium ion, lithium ion, potassium ion and the like.

The alkyl group or fluorinated alkyl group for R ⁷ may be linear, branched or cyclic.
The linear or branched alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and still more preferably 1 to 4 carbon atoms.
The cyclic alkyl group preferably has 4 to 15 carbon atoms, more preferably 4 to 10 carbon atoms, and most preferably 6 to 10 carbon atoms.
Examples of the fluorinated alkyl group include groups in which some or all of the hydrogen atoms of the alkyl group have been substituted with fluorine atoms.
R ⁷ is preferably an alkyl group, preferably a linear alkyl group, and most preferably a methyl group.

Compound (I-1) can be synthesized, for example, by the same method as the method for producing compound (b0-1) described above.
A commercially available compound (I-2) can be used.
Compound (I-1) and compound (I-2) can be reacted, for example, by bringing these compounds into contact with each other in a solvent such as water or dichloromethane.

The structure of the compound obtained in the above step is as follows: ¹ H-nuclear magnetic resonance (NMR) spectrum method, ¹³ C-NMR spectrum method, ¹⁹ F-NMR spectrum method, infrared absorption (IR) spectrum method, mass spectrometry (MS) method. It can be confirmed by general organic analysis methods such as elemental analysis and X-ray crystal diffraction.

≪Acid generator≫
The acid generator according to the fifth aspect of the present invention is composed of the compound (B1) according to the first aspect.
The acid generator is useful as an acid generator for a chemically amplified resist composition, for example, an acid generator component (B) of a resist composition according to the sixth aspect of the present invention described later.

≪Resist composition≫
The resist composition of the sixth aspect of the present invention generates a base component (A) (hereinafter referred to as component (A)) whose solubility in an alkaline developer is changed by the action of an acid, and an acid upon exposure. An acid generator component (B) (hereinafter referred to as component (B)) is contained, and the component (B) is an acid generator (B1) composed of a compound represented by the general formula (b1-1). Including.
When a resist film formed using such a resist composition is selectively exposed at the time of resist pattern formation, an acid is generated from the component (B), and the acid has a solubility in the alkaline developer of the component (A). Change. As a result, while the solubility of the exposed portion of the resist film in the alkaline developer changes, the unexposed portion does not change the solubility in the alkaline developer. In the case of the negative type, the unexposed part is dissolved and removed, and a resist pattern is formed.
The resist composition of the present invention may be a negative resist composition or a positive resist composition.

<(A) component>
As the component (A), organic compounds that are usually used as base material components for chemically amplified resists can be used singly or in combination of two or more.
Here, the “base material component” is an organic compound having a film forming ability, and an organic compound having a molecular weight of 500 or more is preferably used. When the molecular weight of the organic compound is 500 or more, the film-forming ability is improved and a nano-level resist pattern is easily formed.
The organic compound having a molecular weight of 500 or more is largely classified into a low molecular weight organic compound having a molecular weight of 500 or more and less than 2000 (hereinafter referred to as a low molecular compound) and a high molecular weight resin having a molecular weight of 2000 or more (polymer material). Separated. As the low molecular weight compound, a non-polymer is usually used. In the case of a resin (polymer, copolymer), a polystyrene-reduced mass average molecular weight by GPC (gel permeation chromatography) is used as the “molecular weight”. Hereinafter, the term “resin” refers to a resin having a molecular weight of 2000 or more.
As the component (A), a resin whose alkali solubility is changed by the action of an acid can be used, and a low molecular weight material whose alkali solubility is changed by the action of an acid can also be used.

When the resist composition of the present invention is a negative resist composition, as the component (A), a base material component that is soluble in an alkali developer is used, and a crosslinking agent is further added to the negative resist composition.
In such a negative resist composition, when an acid is generated from the component (B) by exposure, the acid acts to cause crosslinking between the base material component and the crosslinking agent, resulting in poor solubility in an alkali developer. To do. Therefore, in the formation of the resist pattern, when the resist film obtained by applying the negative resist composition on the substrate is selectively exposed, the exposed portion turns into poorly soluble in an alkaline developer, while unexposed. Since the portion remains soluble in the alkali developer and does not change, a resist pattern can be formed by alkali development.
As the component (A) of the negative resist composition, a resin that is soluble in an alkali developer (hereinafter referred to as an alkali-soluble resin) is usually used.
As the alkali-soluble resin, a resin having a unit derived from at least one selected from α- (hydroxyalkyl) acrylic acid or a lower alkyl ester of α- (hydroxyalkyl) acrylic acid is a good resist with little swelling. A pattern can be formed, which is preferable. Α- (Hydroxyalkyl) acrylic acid includes acrylic acid in which a hydrogen atom is bonded to the α-position carbon atom to which the carboxy group is bonded, and a hydroxyalkyl group (preferably having 1 carbon atom) in the α-position carbon atom. One or both of [alpha] -hydroxyalkylacrylic acids to which (5) hydroxyalkyl groups) are attached.
As the crosslinking agent, for example, it is usually preferable to use an amino crosslinking agent such as glycoluril having a methylol group or an alkoxymethyl group because a good resist pattern with less swelling can be formed. It is preferable that the compounding quantity of a crosslinking agent is 1-50 mass parts with respect to 100 mass parts of alkali-soluble resin.

  When the resist composition of the present invention is a positive resist composition, as the component (A), a base material component whose solubility in an alkaline developer is increased by the action of an acid is used. The component (A) is hardly soluble in an alkali developer before exposure. When an acid is generated from the component (B) by exposure, the solubility in the alkali developer is increased by the action of the acid. Therefore, in the formation of the resist pattern, when the resist film obtained by applying the positive resist composition on the substrate is selectively exposed, the exposed portion changes from poorly soluble to soluble in an alkaline developer. On the other hand, since the unexposed portion remains hardly soluble in alkali and does not change, a resist pattern can be formed by alkali development.

In the resist composition of the present invention, the component (A) is preferably a base material component whose solubility in an alkaline developer is increased by the action of an acid. That is, the resist composition of the present invention is preferably a positive resist composition.
The component (A) may be a resin component (A1) (hereinafter also referred to as component (A1)) whose solubility in an alkaline developer is increased by the action of an acid. It may be a low molecular compound (A2) (hereinafter sometimes referred to as the component (A2)) whose solubility in a liquid is increased, or a mixture thereof.

[(A1) component]
As the component (A1), resin components (base resins) that are usually used as base components for chemically amplified resists can be used alone or in combination of two or more.
In the present invention, the component (A1) preferably contains a structural unit derived from an acrylate ester.
Here, in the present specification and claims, the “structural unit derived from an acrylate ester” means a structural unit formed by cleavage of an ethylenic double bond of an acrylate ester.
“Acrylic acid esters” include those in which a hydrogen atom is bonded to the carbon atom at the α-position, and those in which a substituent (atom or group other than a hydrogen atom) is bonded to the carbon atom in the α-position. Include concepts. Examples of the substituent include a lower alkyl group and a halogenated lower alkyl group.
Note that the α-position (α-position carbon atom) of a structural unit derived from an acrylate ester means a carbon atom to which a carbonyl group is bonded, unless otherwise specified.
In the acrylate ester, as the lower alkyl group as a substituent at the α-position, specifically, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, Examples include lower linear or branched alkyl groups such as isopentyl group and neopentyl group.
Specific examples of the halogenated lower alkyl group include groups in which part or all of the hydrogen atoms in the above-mentioned “lower alkyl group as a substituent at the α-position” are substituted with halogen atoms. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable.
In the present invention, the α-position of the acrylate ester is preferably a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group, and is a hydrogen atom, a lower alkyl group or a fluorinated lower alkyl group. In view of industrial availability, a hydrogen atom or a methyl group is most preferable.

The component (A1) particularly preferably has a structural unit (a1) derived from an acrylate ester containing an acid dissociable, dissolution inhibiting group.
In addition to the structural unit (a1), the component (A1) preferably further has a structural unit (a2) derived from an acrylate ester containing a lactone-containing cyclic group.
The component (A1) is a structural unit derived from an acrylate ester containing a polar group-containing aliphatic hydrocarbon group in addition to the structural unit (a1) or in addition to the structural units (a1) and (a2). It is preferable to have (a3).

・ Structural unit (a1)
The acid dissociable, dissolution inhibiting group in the structural unit (a1) has an alkali dissolution inhibiting property that makes the entire component (A1) difficult to dissolve in an alkali developer before dissociation, and dissociates with an acid. This increases the solubility of the entire component in an alkaline developer, and those that have been proposed as acid dissociable, dissolution inhibiting groups for base resins for chemically amplified resists can be used. In general, a group that forms a cyclic or chain tertiary alkyl ester with a carboxy group in (meth) acrylic acid or the like; an acetal-type acid dissociable, dissolution inhibiting group such as an alkoxyalkyl group is widely known. .

Here, the “tertiary alkyl ester” is an ester formed by replacing a hydrogen atom of a carboxy group with a chain or cyclic alkyl group, and the carbonyloxy group (—C (O)). A structure in which the tertiary carbon atom of the chain or cyclic alkyl group is bonded to the terminal oxygen atom of -O-). In this tertiary alkyl ester, when an acid acts, a bond is cut between an oxygen atom and a tertiary carbon atom.
The chain or cyclic alkyl group may have a substituent.
Hereinafter, a group that is acid dissociable by constituting a carboxy group and a tertiary alkyl ester is referred to as a “tertiary alkyl ester type acid dissociable, dissolution inhibiting group” for convenience.
Examples of the tertiary alkyl ester type acid dissociable, dissolution inhibiting group include an aliphatic branched acid dissociable, dissolution inhibiting group and an acid dissociable, dissolution inhibiting group containing an aliphatic cyclic group.

“Aliphatic branched” means having a branched structure having no aromaticity. The structure of the “aliphatic branched acid dissociable, dissolution inhibiting group” is not limited to a group consisting of carbon and hydrogen (hydrocarbon group), but is preferably a hydrocarbon group. The “hydrocarbon group” may be either saturated or unsaturated, but is usually preferably saturated.
As the aliphatic branched acid dissociable, dissolution inhibiting group, a tertiary alkyl group having 4 to 8 carbon atoms is preferable, and specific examples include a tert-butyl group, a tert-pentyl group, and a tert-heptyl group. .

The “aliphatic cyclic group” means a monocyclic group or a polycyclic group having no aromaticity.
The “aliphatic cyclic group” in the structural unit (a1) may or may not have a substituent. Examples of the substituent include a lower alkyl group having 1 to 5 carbon atoms, a fluorine atom, a fluorinated lower alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, an oxygen atom (= O), and the like.
The basic ring structure excluding the substituent of the “aliphatic cyclic group” is not limited to a group consisting of carbon and hydrogen (hydrocarbon group), but is preferably a hydrocarbon group. The “hydrocarbon group” may be either saturated or unsaturated, but is usually preferably saturated. The “aliphatic cyclic group” is preferably a polycyclic group.
Examples of the aliphatic cyclic group include monocycloalkanes, bicycloalkanes, tricycloalkanes, tetracycloalkanes which may or may not be substituted with a lower alkyl group, a fluorine atom or a fluorinated alkyl group. And groups obtained by removing one or more hydrogen atoms from a polycycloalkane. More specific examples include monocycloalkanes such as cyclopentane and cyclohexane, and groups obtained by removing one or more hydrogen atoms from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. .

  Examples of the acid dissociable, dissolution inhibiting group containing an aliphatic cyclic group include a group having a tertiary carbon atom on the ring skeleton of a cyclic alkyl group. Specifically, 2-methyl-2 -Adamantyl group, 2-ethyl-2-adamantyl group, etc. are mentioned. Alternatively, in the structural units represented by the following general formulas (a1 ″ -1) to (a1 ″ -6), an adamantyl group such as a group bonded to an oxygen atom of a carbonyloxy group (—C (O) —O—) An aliphatic cyclic group such as a cyclohexyl group, a cyclopentyl group, a norbornyl group, a tricyclodecanyl group, or a tetracyclododecanyl group, and a branched alkylene group having a tertiary carbon atom bonded thereto. Groups.

［式中、Ｒは水素原子、低級アルキル基またはハロゲン化低級アルキル基を示し；Ｒ^１５、Ｒ^１６はアルキル基（直鎖状、分岐鎖状のいずれでもよく、好ましくは炭素数１〜５である）を示す。］

[Wherein, R represents a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group; R ¹⁵ and R ^{16 each} represents an alkyl group (which may be linear or branched, and preferably has 1 to 5 carbon atoms. Is). ]

  In the general formulas (a1 ″ -1) to (a1 ″ -6), the lower alkyl group or halogenated lower alkyl group of R is a lower alkyl group or halogenated lower alkyl which may be bonded to the α-position of the acrylate ester. It is the same as the alkyl group.

The “acetal-type acid dissociable, dissolution inhibiting group” is generally bonded to an oxygen atom by substituting a hydrogen atom at the terminal of an alkali-soluble group such as a carboxy group or a hydroxyl group. When an acid is generated by exposure, the acid acts to break the bond between the acetal acid dissociable, dissolution inhibiting group and the oxygen atom to which the acetal acid dissociable, dissolution inhibiting group is bonded.
Examples of the acetal type acid dissociable, dissolution inhibiting group include a group represented by the following general formula (p1).

［式中、Ｒ^１’，Ｒ^２’はそれぞれ独立して水素原子または低級アルキル基を表し、ｎは０〜３の整数を表し、Ｙは低級アルキル基または脂肪族環式基を表す。］

[Wherein, R ¹ ′ and R ² ′ each independently represents a hydrogen atom or a lower alkyl group, n represents an integer of 0 to 3, and Y represents a lower alkyl group or an aliphatic cyclic group. ]

In the above formula, n is preferably an integer of 0 to 2, more preferably 0 or 1, and most preferably 0.
Examples of the lower alkyl group for R ¹ ′ and R ² ′ include the same lower alkyl groups as those described above for R. A methyl group or an ethyl group is preferable, and a methyl group is most preferable.
In the present invention, it is preferable that at least one of R ¹ ′ and R ² ′ is a hydrogen atom. That is, the acid dissociable, dissolution inhibiting group (p1) is preferably a group represented by the following general formula (p1-1).

［式中、Ｒ^１’、ｎ、Ｙは上記と同様である。］

[Wherein R ¹ ′, n and Y are the same as described above. ]

Examples of the lower alkyl group for Y include the same lower alkyl groups as those described above for R.
The aliphatic cyclic group for Y can be appropriately selected from monocyclic or polycyclic aliphatic cyclic groups that have been proposed in a number of conventional ArF resists. For example, the above “aliphatic ring” Examples thereof are the same as those in the formula group.

  Examples of the acetal type acid dissociable, dissolution inhibiting group also include a group represented by the following general formula (p2).

［式中、Ｒ^１７、Ｒ^１８はそれぞれ独立して直鎖状もしくは分岐鎖状のアルキル基または水素原子であり、Ｒ^１９は直鎖状、分岐鎖状または環状のアルキル基である。または、Ｒ^１７およびＲ^１９がそれぞれ独立に直鎖状または分岐鎖状のアルキレン基であって、Ｒ^１７の末端とＲ^１９の末端とが結合して環を形成していてもよい。］

[Wherein, R ¹⁷ and R ¹⁸ each independently represent a linear or branched alkyl group or a hydrogen atom, and R ¹⁹ represents a linear, branched or cyclic alkyl group. Alternatively, R ¹⁷ and R ¹⁹ may be each independently a linear or branched alkylene group, and the end of R ^{17 and} the end of R ¹⁹ may be bonded to form a ring. ]

In R ¹⁷ and R ¹⁸ , the alkyl group preferably has 1 to 15 carbon atoms, may be linear or branched, and is preferably an ethyl group or a methyl group, and most preferably a methyl group. In particular, it is preferable that one of R ¹⁷ and R ¹⁸ is a hydrogen atom and the other is a methyl group.
R ¹⁹ is a linear, branched or cyclic alkyl group, preferably having 1 to 15 carbon atoms, and may be any of linear, branched or cyclic.
When R ¹⁹ is linear or branched, it preferably has 1 to 5 carbon atoms, more preferably an ethyl group or a methyl group, and most preferably an ethyl group.
When R ¹⁹ is cyclic, it preferably has 4 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specifically, one or more polycycloalkanes such as monocycloalkane, bicycloalkane, tricycloalkane, and tetracycloalkane, which may or may not be substituted with a fluorine atom or a fluorinated alkyl group, are included. Examples include a group excluding a hydrogen atom. Specific examples include monocycloalkanes such as cyclopentane and cyclohexane, and groups obtained by removing one or more hydrogen atoms from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Among them, a group obtained by removing one or more hydrogen atoms from adamantane is preferable.
In the above formula, R ¹⁷ and R ¹⁹ are each independently a linear or branched alkylene group (preferably an alkylene group having 1 to 5 carbon atoms), and the end of R ^{19 and} the end of R ¹⁷ And may be combined.
In this case, a cyclic group is formed by R ¹⁷ , R ¹⁹ , the oxygen atom to which R ¹⁹ is bonded, and the carbon atom to which the oxygen atom and R ¹⁷ are bonded. The cyclic group is preferably a 4- to 7-membered ring, and more preferably a 4- to 6-membered ring. Specific examples of the cyclic group include a tetrahydropyranyl group and a tetrahydrofuranyl group.

  As the structural unit (a1), one or more selected from the group consisting of structural units represented by the following general formula (a1-0-1) and structural units represented by the following general formula (a1-0-2): Is preferably used.

［式中、Ｒは水素原子、低級アルキル基またはハロゲン化低級アルキル基を示し；Ｘ^１は酸解離性溶解抑制基を示す。］

[Wherein, R represents a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group; and X ¹ represents an acid dissociable, dissolution inhibiting group. ]

［式中、Ｒは水素原子、低級アルキル基またはハロゲン化低級アルキル基を示し；Ｘ^２は酸解離性溶解抑制基を示し；Ｙ^２はアルキレン基または脂肪族環式基を示す。］

[Wherein, R represents a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group; X ² represents an acid dissociable, dissolution inhibiting group; Y ² represents an alkylene group or an aliphatic cyclic group. ]

In general formula (a1-0-1), the lower alkyl group or halogenated lower alkyl group for R is the same as the lower alkyl group or halogenated lower alkyl group that may be bonded to the α-position of the acrylate ester. .
X ¹ is not particularly limited as long as it is an acid dissociable, dissolution inhibiting group, and examples thereof include the above-described tertiary alkyl ester type acid dissociable, dissolution inhibiting group and acetal type acid dissociable, dissolution inhibiting group. And tertiary alkyl ester type acid dissociable, dissolution inhibiting groups are preferred.

In general formula (a1-0-2), R is the same as defined above.
X ² is the same as X ¹ in formula (a1-0-1).
Y ² is preferably an alkylene group having 1 to 10 carbon atoms or a divalent aliphatic cyclic group, and a group in which two or more hydrogen atoms are removed is used as the aliphatic cyclic group. Except for the above, the same “aliphatic cyclic group” as described above can be used.
When Y ² is an alkylene group having 1 to 10 carbon atoms, it is more preferably 1 to 6 carbon atoms, particularly preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms. .
When Y ² is a divalent aliphatic cyclic group, a group in which two or more hydrogen atoms have been removed from cyclopentane, cyclohexane, norbornane, isobornane, adamantane, tricyclodecane, or tetracyclododecane is particularly preferable. .

  More specifically, examples of the structural unit (a1) include structural units represented by the following general formulas (a1-1) to (a1-4).

［上記式中、Ｘ’は第３級アルキルエステル型酸解離性溶解抑制基を表し、Ｙは炭素数１〜５の低級アルキル基、または脂肪族環式基を表し；ｎは０〜３の整数を表し；Ｙ^２はアルキレン基または脂肪族環式基を表し；Ｒは前記と同じであり、Ｒ^１’、Ｒ^２’はそれぞれ独立して水素原子または炭素数１〜５の低級アルキル基を表す。］

[In the above formula, X ′ represents a tertiary alkyl ester type acid dissociable, dissolution inhibiting group, Y represents a lower alkyl group having 1 to 5 carbon atoms, or an aliphatic cyclic group; Y ² represents an alkylene group or an aliphatic cyclic group; R is the same as defined above; R ¹ ′ and R ² ′ each independently represent a hydrogen atom or a lower alkyl group having 1 to 5 carbon atoms; Represents. ]

Wherein, X 'include those of the same tertiary alkyl ester-type acid dissociable, dissolution inhibiting groups as those described above for X ^{1.
R 1 ', R 2',} n, as the Y, respectively, ^{R 1} in the general formula listed in the description of "acetal-type acid dissociable, dissolution inhibiting group" described above ^{(p1) ', R 2'} , n, Y The same thing is mentioned.
The Y ^2, the same groups as those described above for ^{Y 2} in the general formula (a1-0-2).

  Specific examples of the structural units represented by the general formulas (a1-1) to (a1-4) are shown below.

Among the above, the structural unit represented by the general formula (a1-1) is preferable, and specifically, (a1-1-1) to (a1-1-6) and (a1-1-35) to (a1). It is more preferable to use at least one selected from the group -1-41).
Furthermore, as the structural unit (a1), in particular, those represented by the following general formula (a1-1-01) including the structural units of the formulas (a1-1-1) to (a1-1-4) The following general formula (a1-1-02) including the structural units of formulas (a1-1-35) to (a1-1-41) is also preferable.

（式中、Ｒは水素原子、低級アルキル基またはハロゲン化低級アルキル基を示し、Ｒ^１１は低級アルキル基を示す。）

(In the formula, R represents a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group, and R ¹¹ represents a lower alkyl group.)

（式中、Ｒは水素原子、低級アルキル基またはハロゲン化低級アルキル基を示し、Ｒ^１２は低級アルキル基を示す。ｈは１〜３の整数を表す。）

(In the formula, R represents a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group, R ¹² represents a lower alkyl group, and h represents an integer of 1 to 3.)

In general formula (a1-1-01), R is the same as defined above.
The lower alkyl group for R ^{11 is the same as} the lower alkyl group for R, and is preferably a methyl group or an ethyl group.
In general formula (a1-1-02), R is the same as defined above.
The lower alkyl group for R ^{12 is the same as} the lower alkyl group for R, preferably a methyl group or an ethyl group, and most preferably an ethyl group. h is preferably 1 or 2, and most preferably 2.

As the structural unit (a1), one type may be used alone, or two or more types may be used in combination.
In the component (A1), the proportion of the structural unit (a1) is preferably 10 to 80 mol%, more preferably 20 to 70 mol%, more preferably 25 to 50 mol%, based on all structural units constituting the component (A1). Is more preferable. By setting it to the lower limit value or more, a pattern can be easily obtained when the resist composition is used, and by setting it to the upper limit value or less, it is possible to balance with other structural units.

・ Structural unit (a2)
The structural unit (a2) is a structural unit derived from an acrylate ester containing a lactone-containing cyclic group.
Here, the lactone-containing cyclic group refers to a cyclic group containing one ring (lactone ring) containing an —O—C (O) — structure. The lactone ring is counted as the first ring, and when it is only the lactone ring, it is called a monocyclic group, and when it has another ring structure, it is called a polycyclic group regardless of the structure.
When the component (A1) is used for forming a resist film, the lactone cyclic group of the structural unit (a2) increases the adhesion of the resist film to the substrate or has an affinity for a developer containing water. It is effective in raising.

As the structural unit (a2), any unit can be used without any particular limitation.
Specifically, examples of the lactone-containing monocyclic group include groups in which one hydrogen atom has been removed from γ-butyrolactone. Examples of the lactone-containing polycyclic group include groups in which one hydrogen atom has been removed from a bicycloalkane, tricycloalkane, or tetracycloalkane having a lactone ring.
More specifically, examples of the structural unit (a2) include structural units represented by general formulas (a2-1) to (a2-5) shown below.

［式中、Ｒは水素原子、低級アルキル基またはハロゲン化低級アルキル基であり、Ｒ’は水素原子、低級アルキル基、または炭素数１〜５のアルコキシ基であり、ｍは０または１の整数であり、Ａは炭素数１〜５のアルキレン基または酸素原子である。］

[Wherein, R is a hydrogen atom, a lower alkyl group or a halogenated lower alkyl group, R ′ is a hydrogen atom, a lower alkyl group, or an alkoxy group having 1 to 5 carbon atoms, and m is an integer of 0 or 1] And A is an alkylene group having 1 to 5 carbon atoms or an oxygen atom. ]

R in the general formulas (a2-1) to (a2-5) is the same as R in the structural unit (a1).
The lower alkyl group for R ′ is the same as the lower alkyl group for R in the structural unit (a1).
Specific examples of the alkylene group having 1 to 5 carbon atoms of A include a methylene group, an ethylene group, an n-propylene group, and an isopropylene group.
In general formulas (a2-1) to (a2-5), R ′ is preferably a hydrogen atom in view of industrial availability.
Below, the specific structural unit of the said general formula (a2-1)-(a2-5) is illustrated.

  As the structural unit (a2), at least one selected from the group consisting of structural units represented by the general formulas (a2-1) to (a2-5) is preferable, and the general formulas (a2-1) to ( At least one selected from the group consisting of structural units represented by a2-3) is more preferred. Among them, chemical formulas (a2-1-1), (a2-1-2), (a2-2-1), (a2-2-2), (a2-3-1), (a2-3-2) ), (A2-3-9) and (a2-3-10), at least one selected from the group consisting of structural units represented by (a2-3-10) is preferred.

As the structural unit (a2), one type may be used alone, or two or more types may be used in combination.
In the component (A1), the proportion of the structural unit (a2) is preferably 5 to 60 mol%, more preferably 10 to 50 mol%, based on the total of all the structural units constituting the component (A1). 50 mol% is more preferable. By making it the lower limit value or more, the effect of containing the structural unit (a2) can be sufficiently obtained, and by making it the upper limit value or less, it is possible to balance with other structural units.

・ Structural unit (a3)
The structural unit (a3) is a structural unit derived from an acrylate ester containing a polar group-containing aliphatic hydrocarbon group.
When the component (A1) has the structural unit (a3), the hydrophilicity of the component (A1) is increased, the affinity with the developer is increased, the alkali solubility in the exposed area is improved, and the resolution is improved. Contributes to improvement.
Examples of the polar group include a hydroxyl group, a cyano group, a carboxy group, and a hydroxyalkyl group in which a part of hydrogen atoms of an alkyl group is substituted with a fluorine atom. A hydroxyl group is particularly preferable.
Examples of the aliphatic hydrocarbon group include a linear or branched hydrocarbon group having 1 to 10 carbon atoms (preferably an alkylene group) and a polycyclic aliphatic hydrocarbon group (polycyclic group). It is done. As the polycyclic group, for example, a resin for a resist composition for ArF excimer laser can be appropriately selected from among many proposed ones. The polycyclic group preferably has 7 to 30 carbon atoms.
Among them, a structural unit derived from an acrylate ester containing an aliphatic polycyclic group containing a hydroxyalkyl group in which a part of hydrogen atoms of a hydroxyl group, a cyano group, a carboxy group, or an alkyl group is substituted with a fluorine atom Is more preferable. Examples of the polycyclic group include groups in which two or more hydrogen atoms have been removed from bicycloalkane, tricycloalkane, tetracycloalkane and the like. Specific examples include groups in which two or more hydrogen atoms have been removed from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Among these polycyclic groups, there are groups in which two or more hydrogen atoms have been removed from adamantane, groups in which two or more hydrogen atoms have been removed from norbornane, and groups in which two or more hydrogen atoms have been removed from tetracyclododecane. Industrially preferable.

  The structural unit (a3) is derived from a hydroxyethyl ester of acrylic acid when the hydrocarbon group in the polar group-containing aliphatic hydrocarbon group is a linear or branched hydrocarbon group having 1 to 10 carbon atoms. When the hydrocarbon group is a polycyclic group, a structural unit represented by the following formula (a3-1), a structural unit represented by (a3-2), (a3-3) ) Is preferable.

（式中、Ｒは前記と同じであり、ｊは１〜３の整数であり、ｋは１〜３の整数であり、ｔ’は１〜３の整数であり、ｌは１〜５の整数であり、ｓは１〜３の整数である。）

(Wherein R is the same as above, j is an integer of 1 to 3, k is an integer of 1 to 3, t 'is an integer of 1 to 3, and l is an integer of 1 to 5) And s is an integer of 1 to 3.)

In formula (a3-1), j is preferably 1 or 2, and more preferably 1. When j is 2, it is preferable that the hydroxyl group is bonded to the 3rd and 5th positions of the adamantyl group. When j is 1, it is preferable that the hydroxyl group is bonded to the 3-position of the adamantyl group. j is preferably 1, and a hydroxyl group bonded to the 3rd position of the adamantyl group is particularly preferred.
In formula (a3-2), k is preferably 1. The cyano group is preferably bonded to the 5th or 6th position of the norbornyl group.
In formula (a3-3), t ′ is preferably 1. l is preferably 1. s is preferably 1. These preferably have a 2-norbornyl group or a 3-norbornyl group bonded to the terminal of the carboxy group of acrylic acid. The fluorinated alkyl alcohol is preferably bonded to the 5th or 6th position of the norbornyl group.

As the structural unit (a3), one type may be used alone, or two or more types may be used in combination.
In the component (A1), the proportion of the structural unit (a3) is preferably 5 to 50 mol%, more preferably 5 to 40 mol%, and more preferably 5 to 25 mol% with respect to all the structural units constituting the component (A1). Is more preferable. By setting it to the lower limit value or more, the effect of containing the structural unit (a3) can be sufficiently obtained, and by setting it to the upper limit value or less, it is possible to balance with other structural units.

・ Structural unit (a4)
The component (A1) may contain other structural units (a4) other than the structural units (a1) to (a3) as long as the effects of the present invention are not impaired.
The structural unit (a4) is not particularly limited as long as it is another structural unit that is not classified into the structural units (a1) to (a3) described above, and is for ArF excimer laser and KrF excimer laser (preferably ArF excimer). A number of hitherto known materials can be used for resist resins such as lasers.
As the structural unit (a4), for example, a structural unit derived from an acrylate ester containing a non-acid-dissociable aliphatic polycyclic group is preferable. Examples of the polycyclic group include those exemplified in the case of the structural unit (a1), and for ArF excimer laser and KrF excimer laser (preferably for ArF excimer laser). A number of hitherto known materials can be used as the resin component of the resist composition.
In particular, at least one selected from a tricyclodecanyl group, an adamantyl group, a tetracyclododecanyl group, an isobornyl group, and a norbornyl group is preferable in terms of industrial availability. These polycyclic groups may have a linear or branched alkyl group having 1 to 5 carbon atoms as a substituent.
Specific examples of the structural unit (a4) include those represented by the following general formulas (a4-1) to (a4-5).

（式中、Ｒは前記と同じである。）

(In the formula, R is as defined above.)

  When the structural unit (a4) is contained in the component (A1), the proportion of the structural unit (a4) in the component (A1) is 1 to 30 with respect to the total of all the structural units constituting the component (A1). Mol% is preferable and 10 to 20 mol% is more preferable.

In the present invention, the component (A1) preferably contains a copolymer having the structural units (a1), (a2) and (a3). Examples of the copolymer include a copolymer composed of the structural units (a1), (a2) and (a3), a copolymer composed of the structural units (a1), (a2), (a3) and (a4). Can be mentioned.
As such a copolymer, for example, those containing three kinds of structural units represented by the following general formula (A1-11) are preferable.

［式中、Ｒ^ａ、Ｒ^ｂ、Ｒ^ｃはそれぞれ独立に前記Ｒと同じであり、Ｒ^１１は低級アルキル基である。］

[Wherein, R ^a , R ^b and R ^c are each independently the same as R, and R ¹¹ is a lower alkyl group. ]

Wherein ^(A1-11), the lower alkyl group for ^{R 11} is the same as ^{R 11} in the general formula (a1-1-01), a methyl group or an ethyl group is preferable.

The component (A1) can be obtained by polymerizing a monomer for deriving each structural unit by a known radical polymerization using a radical polymerization initiator such as azobisisobutyronitrile (AIBN).
Further, for the component (A1), in the polymerization, a chain transfer agent such as HS—CH ₂ —CH ₂ —CH ₂ —C (CF ₃ ) ₂ —OH is used in combination, so that the terminal A —C (CF ₃ ) ₂ —OH group may be introduced into the. As described above, a copolymer introduced with a hydroxyalkyl group in which a part of hydrogen atoms of the alkyl group is substituted with a fluorine atom reduces development defects and LER (line edge roughness: uneven unevenness of line side walls). It is effective in reducing

The mass average molecular weight (Mw) (polystyrene conversion standard by gel permeation chromatography) of the component (A1) is not particularly limited, but is preferably 2000 to 50000, more preferably 3000 to 30000, and 5000 to 20000. Most preferred. If it is smaller than the upper limit of this range, there is sufficient solubility in a resist solvent to be used as a resist, and if it is larger than the lower limit of this range, dry etching resistance and resist pattern cross-sectional shape are good.
Further, the dispersity (Mw / Mn) is preferably 1.0 to 5.0, more preferably 1.0 to 3.0, and most preferably 1.2 to 2.5. Mn represents a number average molecular weight.

[(A2) component]
As the component (A2), a low molecular compound having a molecular weight of 500 or more and less than 2000 and having an acid dissociable, dissolution inhibiting group and a hydrophilic group as exemplified in the description of the component (A1) above is preferable. Specifically, a compound in which a part of hydrogen atoms of a hydroxyl group of a compound having a plurality of phenol skeletons is substituted with the acid dissociable, dissolution inhibiting group can be mentioned.
The component (A2) is, for example, a part of the hydrogen atom of the hydroxyl group of a low molecular weight phenol compound known as a sensitizer in a non-chemically amplified g-line or i-line resist or a heat resistance improver. Those substituted with a soluble dissolution inhibiting group are preferred and can be arbitrarily used.
Examples of such low molecular weight phenol compounds include bis (4-hydroxyphenyl) methane, bis (2,3,4-trihydroxyphenyl) methane, 2- (4-hydroxyphenyl) -2- (4′-hydroxyphenyl). ) Propane, 2- (2,3,4-trihydroxyphenyl) -2- (2 ′, 3 ′, 4′-trihydroxyphenyl) propane, tris (4-hydroxyphenyl) methane, bis (4-hydroxy-) 3,5-dimethylphenyl) -2-hydroxyphenylmethane, bis (4-hydroxy-2,5-dimethylphenyl) -2-hydroxyphenylmethane, bis (4-hydroxy-3,5-dimethylphenyl) -3, 4-dihydroxyphenylmethane, bis (4-hydroxy-2,5-dimethylphenyl) -3,4-dihydroxyph Phenylmethane, bis (4-hydroxy-3-methylphenyl) -3,4-dihydroxyphenylmethane, bis (3-cyclohexyl-4-hydroxy-6-methylphenyl) -4-hydroxyphenylmethane, bis (3-cyclohexyl- 4-hydroxy-6-methylphenyl) -3,4-dihydroxyphenylmethane, 1- [1- (4-hydroxyphenyl) isopropyl] -4- [1,1-bis (4-hydroxyphenyl) ethyl] benzene, Examples include 2, 3, 4 nuclei of formalin condensates of phenols such as phenol, m-cresol, p-cresol or xylenol. Of course, it is not limited to these.
The acid dissociable, dissolution inhibiting group is not particularly limited, and examples thereof include those described above.

As the component (A), one type may be used alone, or two or more types may be used in combination.
In the resist composition of the present invention, the content of the component (A) may be adjusted according to the resist film thickness to be formed.

<(B) component>
The component (B) includes an acid generator (B1) (hereinafter sometimes referred to as the component (B1)) composed of the compound represented by the general formula (b1-1). The component (B1) is the same as the compound (B1) of the present invention.
(B1) A component can be used 1 type or in mixture of 2 or more types.
In the resist composition of the present invention, the content of the component (B1) in the component (B) is preferably 40% by mass or more, more preferably 70% by mass or more, and may be 100% by mass. Most preferably, it is 100 mass%. By being at least the lower limit of the range, lithography properties such as resolution and line width roughness (LWR) are improved when a resist pattern is formed using the resist composition of the present invention.

In the component (B), an acid generator (B2) other than the component (B1) (hereinafter referred to as the component (B2)) may be used in combination with the component (B1).
The component (B2) is not particularly limited as long as it is other than the component (B1), and those that have been proposed as acid generators for chemically amplified resists can be used.
Examples of such acid generators include onium salt acid generators such as iodonium salts and sulfonium salts, oxime sulfonate acid generators, bisalkyl or bisarylsulfonyldiazomethanes, and poly (bissulfonyl) diazomethanes. There are various known diazomethane acid generators, nitrobenzyl sulfonate acid generators, imino sulfonate acid generators, disulfone acid generators, and the like.

  As the onium salt acid generator, for example, a compound represented by the following general formula (b-1) or (b-2) can be used.

［式中、Ｒ^１”〜Ｒ^３”，Ｒ^５”〜Ｒ^６”は、それぞれ独立に、アリール基またはアルキル基を表し；式（ｂ−１）におけるＲ^１”〜Ｒ^３”のうち、いずれか２つが相互に結合して式中のイオウ原子と共に環を形成してもよく；Ｒ^４”は、直鎖状、分岐鎖状または環状のアルキル基またはフッ素化アルキル基を表し；Ｒ^１”〜Ｒ^３”のうち少なくとも１つはアリール基を表し、Ｒ^５”〜Ｒ^６”のうち少なくとも１つはアリール基を表す。］

[Wherein, R ¹ ″ to R ³ ″ and R ⁵ ″ to R ⁶ ″ each independently represents an aryl group or an alkyl group; among R ¹ ″ to R ³ ″ in formula (b-1), Any two may be bonded together to form a ring with the sulfur atom in the formula; R ⁴ ″ represents a linear, branched or cyclic alkyl group or a fluorinated alkyl group; R ¹ At least one of “˜R ³ ” represents an aryl group, and at least one of R ⁵ ”to R ⁶ ” represents an aryl group.]

In formula (b-1), R ¹ ″ to R ³ ″ each independently represents an aryl group or an alkyl group. In addition, any two of R ¹ ″ to R ³ ″ in formula (b-1) may be bonded to each other to form a ring together with the sulfur atom in the formula.
Further, at least one of R ¹ ″ to R ³ ″ represents an aryl group. Of R ¹ ″ to R ³ ″, two or more are preferably aryl groups, and most preferably all R ¹ ″ to R ³ ″ are aryl groups.
The aryl group for R ¹ ″ to R ³ ″ is not particularly limited, and is, for example, an aryl group having 6 to 20 carbon atoms, in which part or all of the hydrogen atoms are alkyl groups, alkoxy groups It may or may not be substituted with a group, a halogen atom, a hydroxyl group or the like. The aryl group is preferably an aryl group having 6 to 10 carbon atoms because it can be synthesized at a low cost. Specific examples include a phenyl group and a naphthyl group.
The alkyl group that may be substituted for the hydrogen atom of the aryl group is preferably an alkyl group having 1 to 5 carbon atoms, and is a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group. Is most preferred.
As the alkoxy group that may be substituted for the hydrogen atom of the aryl group, an alkoxy group having 1 to 5 carbon atoms is preferable, and a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, Most preferred is a tert-butoxy group.
The alkoxy group that may be substituted for the hydrogen atom of the aryl group is preferably an alkoxy group having 1 to 5 carbon atoms, and most preferably a methoxy group or an ethoxy group.
The halogen atom that may be substituted for the hydrogen atom of the aryl group is preferably a fluorine atom.
The alkyl group for R 1 ^{"~R 3",} is not particularly limited, for example, linear C1-10, branched or cyclic alkyl group, and the like. It is preferable that it is C1-C5 from the point which is excellent in resolution. Specific examples include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, an n-pentyl group, a cyclopentyl group, a hexyl group, a cyclohexyl group, a nonyl group, and a decanyl group. A methyl group is preferable because it is excellent in resolution and can be synthesized at low cost.
Among these, R ¹ ″ to R ³ ″ are most preferably a phenyl group or a naphthyl group, respectively.

When any two of R ¹ ″ to R ³ ″ in the formula (b-1) are bonded to each other to form a ring together with the sulfur atom in the formula, a 3 to 10 membered ring including the sulfur atom is formed. It is preferable that a 5- to 7-membered ring is formed.
When any two of R ¹ ″ to R ³ ″ in formula (b-1) are bonded to each other to form a ring together with the sulfur atom in the formula, the remaining one may be an aryl group preferable. Examples of the aryl group include the same aryl groups as those described above for R ¹ ″ to R ³ ″.

R ⁴ ″ represents a linear, branched or cyclic alkyl group or a fluorinated alkyl group.
The linear or branched alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and most preferably 1 to 4 carbon atoms.
The cyclic alkyl group is a cyclic group as indicated by R ¹ ″ and preferably has 4 to 15 carbon atoms, more preferably 4 to 10 carbon atoms, and more preferably 6 carbon atoms. Most preferably, it is -10.
The fluorinated alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and most preferably 1 to 4 carbon atoms. The fluorination rate of the fluorinated alkyl group (ratio of fluorine atoms in the alkyl group) is preferably 10 to 100%, more preferably 50 to 100%. Particularly, all the hydrogen atoms are substituted with fluorine atoms. A fluorinated alkyl group (perfluoroalkyl group) is preferable because the strength of the acid is increased.
R ⁴ ″ is most preferably a linear or cyclic alkyl group or a fluorinated alkyl group.

In formula (b-2), R ⁵ ″ to R ⁶ ″ each independently represents an aryl group or an alkyl group. At least one of R ⁵ ″ to R ⁶ ″ represents an aryl group. It is preferable that all of R ⁵ ″ to R ⁶ ″ are aryl groups.
As the aryl group for R ⁵ ″ to R ⁶ ″, the same as the aryl groups for R ¹ ″ to R ³ ″ can be used.
Examples of the alkyl group for R ⁵ ″ to R ⁶ ″ include the same as the alkyl group for R ¹ ″ to R ³ ″.
Among these, it is most preferable that all of R ⁵ ″ to R ⁶ ″ are phenyl groups.
"As ^{R 4} in the formula (b-1)" ^{R 4} in the In the formula (b-2) include the same as.

Specific examples of the onium salt acid generators represented by formulas (b-1) and (b-2) include diphenyliodonium trifluoromethanesulfonate or nonafluorobutanesulfonate, bis (4-tert-butylphenyl) iodonium. Trifluoromethane sulfonate or nonafluorobutane sulfonate, triphenylsulfonium trifluoromethane sulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate, tri (4-methylphenyl) sulfonium trifluoromethane sulfonate, its heptafluoropropane sulfonate or its Nonafluorobutanesulfonate, dimethyl (4-hydroxynaphthyl) sulfonium trifluoromethanesulfonate, its heptaful Lopropanesulfonate or its nonafluorobutanesulfonate, trifluoromethanesulfonate of monophenyldimethylsulfonium, its heptafluoropropanesulfonate or its nonafluorobutanesulfonate; trifluoromethanesulfonate of diphenylmonomethylsulfonium, its heptafluoropropanesulfonate or its nonafluorobutanesulfonate (4-methylphenyl) diphenylsulfonium trifluoromethanesulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate, (4-methoxyphenyl) diphenylsulfonium trifluoromethanesulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate , Trifluoromethanesulfonate of tri (4-tert-butyl) phenylsulfonium, its heptafluoropropanesulfonate or its nonafluorobutanesulfonate, trifluoromethanesulfonate of diphenyl (1- (4-methoxy) naphthyl) sulfonium, its heptafluoropropane Sulfonate or its nonafluorobutane sulfonate, di (1-naphthyl) phenyl sulphonium trifluoromethane sulphonate, its heptafluoropropane sulphonate or its nonafluorobutane sulphonate; 1-phenyltetrahydrothiophenium trifluoromethane sulphonate, its heptafluoropropane sulphonate Or nonafluorobutanesulfonate thereof; 1- (4-methylphenyl) ) Tetrahydrothiophenium trifluoromethanesulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate; 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiophenium trifluoromethanesulfonate, its heptafluoropropane sulfonate 1- (4-methoxynaphthalen-1-yl) tetrahydrothiophenium trifluoromethanesulfonate, its heptafluoropropanesulfonate or its nonafluorobutanesulfonate; 1- (4-ethoxynaphthalene-1- Yl) tetrahydrothiophenium trifluoromethanesulfonate, its heptafluoropropanesulfonate or its nonaflu 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium trifluoromethanesulfonate, its heptafluoropropanesulfonate or its nonafluorobutanesulfonate; 1-phenyltetrahydrothiopyranium trifluoromethanesulfonate , Its heptafluoropropane sulfonate or its nonafluorobutane sulfonate; 1- (4-hydroxyphenyl) tetrahydrothiopyranium trifluoromethane sulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate; 1- (3,5-dimethyl -4-Hydroxyphenyl) tetrahydrothiopyranium trifluoromethanesulfonate, its heptafluoropropanes Honeto or nonafluorobutanesulfonate; 1- (4-methylphenyl) trifluoromethanesulfonate tetrahydrothiophenium Pila chloride, heptafluoropropane sulfonate or its nonafluorobutane sulfonate, and the like.
In addition, onium salts in which the anion portion of these onium salts is replaced with methanesulfonate, n-propanesulfonate, n-butanesulfonate, or n-octanesulfonate can also be used.

  In addition, in the general formula (b-1) or (b-2), an onium salt-based acid generator in which the anion moiety is replaced with an anion moiety represented by the following general formula (b-3) or (b-4). Can also be used (the cation moiety is the same as (b-1) or (b-2)).

［式中、Ｘ”は、少なくとも１つの水素原子がフッ素原子で置換された炭素数２〜６のアルキレン基を表し；Ｙ”、Ｚ”は、それぞれ独立に、少なくとも１つの水素原子がフッ素原子で置換された炭素数１〜１０のアルキル基を表す。］

[Wherein X ″ represents an alkylene group having 2 to 6 carbon atoms in which at least one hydrogen atom is substituted with a fluorine atom; Y ″ and Z ″ each independently represent at least one hydrogen atom as a fluorine atom; Represents an alkyl group having 1 to 10 carbon atoms and substituted with

X ″ is a linear or branched alkylene group in which at least one hydrogen atom is substituted with a fluorine atom, and the alkylene group has 2 to 6 carbon atoms, preferably 3 to 5 carbon atoms, Most preferably, it has 3 carbon atoms.
Y ″ and Z ″ are each independently a linear or branched alkyl group in which at least one hydrogen atom is substituted with a fluorine atom, and the alkyl group has 1 to 10 carbon atoms, preferably Has 1 to 7 carbon atoms, more preferably 1 to 3 carbon atoms.
The carbon number of the alkylene group of X ″ or the carbon number of the alkyl group of Y ″ and Z ″ is preferably as small as possible because the solubility in the resist solvent is good within the above carbon number range.
In addition, in the alkylene group of X ″ or the alkyl group of Y ″ and Z ″, as the number of hydrogen atoms substituted with fluorine atoms increases, the strength of the acid increases, and high-energy light or electron beam of 200 nm or less The ratio of fluorine atoms in the alkylene group or alkyl group, that is, the fluorination rate is preferably 70 to 100%, more preferably 90 to 100%, and most preferably all. Are a perfluoroalkylene group or a perfluoroalkyl group in which a hydrogen atom is substituted with a fluorine atom.

  Moreover, the sulfonium salt which has a cation part represented by the following general formula (b-5) or (b-6) can also be used as an onium salt type | system | group acid generator.

［式中、Ｒ^４１〜Ｒ^４６はそれぞれ独立してアルキル基、アセチル基、アルコキシ基、カルボキシ基、水酸基またはヒドロキシアルキル基であり；ｎ_１〜ｎ_５はそれぞれ独立して０〜３の整数であり、ｎ_６は０〜２の整数である。］

[Wherein R ^{41 to} R ⁴⁶ are each independently an alkyl group, acetyl group, alkoxy group, carboxy group, hydroxyl group or hydroxyalkyl group; n _{1 to} n ₅ are each independently an integer of 0 to 3; There, _{n 6} is an integer of 0-2. ]

In R ^{41 to} R ⁴⁶ , the alkyl group is preferably an alkyl group having 1 to 5 carbon atoms, more preferably a linear or branched alkyl group, and a methyl group, an ethyl group, a propyl group, an isopropyl group, n A butyl group or a tert-butyl group is particularly preferable.
The alkoxy group is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a linear or branched alkoxy group, and particularly preferably a methoxy group or an ethoxy group.
The hydroxyalkyl group is preferably a group in which one or more hydrogen atoms in the alkyl group are substituted with a hydroxy group, and examples thereof include a hydroxymethyl group, a hydroxyethyl group, and a hydroxypropyl group.
When the symbols n _{1 to} n ₆ attached to R ^{41 to} R ⁴⁶ are integers of 2 or more, the plurality of R ^{41 to} R ⁴⁶ may be the same or different.
n ₁ is preferably 0 to 2, more preferably 0 or 1, and still more preferably 0.
n ₂ and n ₃ are preferably each independently 0 or 1, more preferably 0.
n ₄ is preferably 0 to 2, more preferably 0 or 1.
n ₅ is preferably 0 or 1, more preferably 0.
n ₆ is preferably 0 or 1, more preferably 1.

The anion part of the sulfonium salt having a cation part represented by the formula (b-5) or (b-6) is not particularly limited, and is the same as the anion part of the onium salt acid generators proposed so far. It may be a thing. Examples of the anion moiety include fluorinated alkyl sulfonate ions such as the anion moiety (R ^{4 ″} SO ₃ ⁻ ) of the onium salt acid generator represented by the general formula (b-1) or (b-2). An anion moiety represented by the general formula (b-3) or (b-4), etc. Among them, a fluorinated alkyl sulfonate ion is preferable, and a fluorinated alkyl sulfonic acid having 1 to 4 carbon atoms. Ion is more preferable, and linear perfluoroalkylsulfonic acid ions having 1 to 4 carbon atoms are particularly preferable, and specific examples thereof include trifluoromethylsulfonic acid ions, heptafluoro-n-propylsulfonic acid ions, and nonafluoro-n. -Butyl sulfonate ion etc. are mentioned.

  In this specification, the oxime sulfonate acid generator is a compound having at least one group represented by the following general formula (B-1), and has a property of generating an acid upon irradiation with radiation. is there. Such oxime sulfonate-based acid generators are frequently used for chemically amplified resist compositions, and can be arbitrarily selected and used.

（式（Ｂ−１）中、Ｒ^３１、Ｒ^３２はそれぞれ独立に有機基を表す。）

(In formula (B-1), R ³¹ and R ³² each independently represents an organic group.)

The organic groups of R ³¹ and R ³² are groups containing carbon atoms, and atoms other than carbon atoms (for example, hydrogen atoms, oxygen atoms, nitrogen atoms, sulfur atoms, halogen atoms (fluorine atoms, chlorine atoms, etc.), etc.) You may have.
As the organic group for R ^31, a linear, branched, or cyclic alkyl group or aryl group is preferable. These alkyl groups and aryl groups may have a substituent. There is no restriction | limiting in particular as this substituent, For example, a fluorine atom, a C1-C6 linear, branched or cyclic alkyl group etc. are mentioned. Here, “having a substituent” means that part or all of the hydrogen atoms of the alkyl group or aryl group are substituted with a substituent.
As an alkyl group, C1-C20 is preferable, C1-C10 is more preferable, C1-C8 is more preferable, C1-C6 is especially preferable, and C1-C4 is the most preferable. As the alkyl group, a partially or completely halogenated alkyl group (hereinafter sometimes referred to as a halogenated alkyl group) is particularly preferable. The partially halogenated alkyl group means an alkyl group in which a part of hydrogen atoms is substituted with a halogen atom, and the fully halogenated alkyl group means that all of the hydrogen atoms are halogen atoms. Means an alkyl group substituted with Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferable. That is, the halogenated alkyl group is preferably a fluorinated alkyl group.
The aryl group preferably has 4 to 20 carbon atoms, more preferably 4 to 10 carbon atoms, and most preferably 6 to 10 carbon atoms. As the aryl group, a partially or completely halogenated aryl group is particularly preferable. The partially halogenated aryl group means an aryl group in which a part of hydrogen atoms is substituted with a halogen atom, and the fully halogenated aryl group means that all of the hydrogen atoms are halogen atoms. Means an aryl group substituted with.
R ³¹ is particularly preferably an alkyl group having 1 to 4 carbon atoms having no substituent or a fluorinated alkyl group having 1 to 4 carbon atoms.

As the organic group for R ^32, a linear, branched, or cyclic alkyl group, aryl group, or cyano group is preferable. As the alkyl group and aryl group for R ^32, the same alkyl groups and aryl groups as those described above for R ³¹ can be used.
R ³² is particularly preferably a cyano group, an alkyl group having 1 to 8 carbon atoms having no substituent, or a fluorinated alkyl group having 1 to 8 carbon atoms.

  More preferable examples of the oxime sulfonate-based acid generator include compounds represented by the following general formula (B-2) or (B-3).

［式（Ｂ−２）中、Ｒ^３３は、シアノ基、置換基を有さないアルキル基またはハロゲン化アルキル基である。Ｒ^３４はアリール基である。Ｒ^３５は置換基を有さないアルキル基またはハロゲン化アルキル基である。］

[In Formula (B-2), R ³³ represents a cyano group, an alkyl group having no substituent, or a halogenated alkyl group. R ³⁴ is an aryl group. R ³⁵ represents an alkyl group having no substituent or a halogenated alkyl group. ]

［式（Ｂ−３）中、Ｒ^３６はシアノ基、置換基を有さないアルキル基またはハロゲン化アルキル基である。Ｒ^３７は２または３価の芳香族炭化水素基である。Ｒ^３８は置換基を有さないアルキル基またはハロゲン化アルキル基である。ｐ”は２または３である。］

[In Formula (B-3), R ³⁶ represents a cyano group, an alkyl group having no substituent, or a halogenated alkyl group. R ³⁷ is a divalent or trivalent aromatic hydrocarbon group. ^R38 is an alkyl group having no substituent or a halogenated alkyl group. p ″ is 2 or 3.]

In the general formula (B-2), the alkyl group or halogenated alkyl group having no substituent for R ³³ preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and more preferably carbon atoms. Numbers 1 to 6 are most preferable.
R ³³ is preferably a halogenated alkyl group, more preferably a fluorinated alkyl group.
The fluorinated alkyl group for R ³³ is preferably such that the hydrogen atom of the alkyl group is 50% or more fluorinated, more preferably 70% or more fluorinated, and 90% or more fluorinated. Particularly preferred.

As the aryl group of R ³⁴ , one hydrogen atom is removed from an aromatic hydrocarbon ring such as a phenyl group, a biphenyl group, a fluorenyl group, a naphthyl group, an anthryl group, or a phenanthryl group. And a heteroaryl group in which a part of carbon atoms constituting the ring of these groups is substituted with a heteroatom such as an oxygen atom, a sulfur atom, or a nitrogen atom. Among these, a fluorenyl group is preferable.
The aryl group of R ³⁴ may have a substituent such as an alkyl group having 1 to 10 carbon atoms, a halogenated alkyl group, or an alkoxy group. The alkyl group or halogenated alkyl group in the substituent preferably has 1 to 8 carbon atoms, and more preferably 1 to 4 carbon atoms. The halogenated alkyl group is preferably a fluorinated alkyl group.

The alkyl group or halogenated alkyl group having no substituent of R ³⁵ preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and most preferably 1 to 6 carbon atoms.
R ³⁵ is preferably a halogenated alkyl group, more preferably a fluorinated alkyl group.
The fluorinated alkyl group for R ³⁵ is preferably such that the hydrogen atom of the alkyl group is 50% or more fluorinated, more preferably 70% or more fluorinated, and 90% or more fluorinated. Particularly preferred is the strength of the acid generated. Most preferably, it is a fully fluorinated alkyl group in which a hydrogen atom is 100% fluorine-substituted.

In the general formula (B-3), the alkyl group or halogenated alkyl group having no substituent for R ³⁶ is the same as the alkyl group or halogenated alkyl group having no substituent for R ^33. Is mentioned.
Examples of the divalent or trivalent aromatic hydrocarbon group for R ³⁷ include groups obtained by further removing one or two hydrogen atoms from the aryl group for R ³⁴ .
Examples of the alkyl group or halogenated alkyl group having no substituent of R ³⁸ include the same alkyl groups or halogenated alkyl groups as those having no substituent of R ³⁵ .
p ″ is preferably 2.

Specific examples of the oxime sulfonate acid generator include α- (p-toluenesulfonyloxyimino) -benzyl cyanide, α- (p-chlorobenzenesulfonyloxyimino) -benzyl cyanide, α- (4-nitrobenzenesulfonyloxy). Imino) -benzylcyanide, α- (4-nitro-2-trifluoromethylbenzenesulfonyloxyimino) -benzylcyanide, α- (benzenesulfonyloxyimino) -4-chlorobenzylcyanide, α- (benzenesulfonyl) Oxyimino) -2,4-dichlorobenzyl cyanide, α- (benzenesulfonyloxyimino) -2,6-dichlorobenzyl cyanide, α- (benzenesulfonyloxyimino) -4-methoxybenzyl cyanide, α- ( 2-Chlorobenzenesulfonyloxyimino) 4-methoxybenzylcyanide, α- (benzenesulfonyloxyimino) -thien-2-ylacetonitrile, α- (4-dodecylbenzenesulfonyloxyimino) -benzylcyanide, α-[(p-toluenesulfonyloxyimino) -4-methoxyphenyl] acetonitrile, α-[(dodecylbenzenesulfonyloxyimino) -4-methoxyphenyl] acetonitrile, α- (tosyloxyimino) -4-thienyl cyanide, α- (methylsulfonyloxyimino) -1-cyclo Pentenyl acetonitrile, α- (methylsulfonyloxyimino) -1-cyclohexenylacetonitrile, α- (methylsulfonyloxyimino) -1-cycloheptenylacetonitrile, α- (methylsulfonyloxyimino) -1-cyclooctene Acetonitrile, α- (trifluoromethylsulfonyloxyimino) -1-cyclopentenylacetonitrile, α- (trifluoromethylsulfonyloxyimino) -cyclohexylacetonitrile, α- (ethylsulfonyloxyimino) -ethylacetonitrile, α- (propyl Sulfonyloxyimino) -propylacetonitrile, α- (cyclohexylsulfonyloxyimino) -cyclopentylacetonitrile, α- (cyclohexylsulfonyloxyimino) -cyclohexylacetonitrile, α- (cyclohexylsulfonyloxyimino) -1-cyclopentenylacetonitrile, α- ( Ethylsulfonyloxyimino) -1-cyclopentenylacetonitrile, α- (isopropylsulfonyloxyimino) -1-cyclope N-tenyl acetonitrile, α- (n-butylsulfonyloxyimino) -1-cyclopentenylacetonitrile, α- (ethylsulfonyloxyimino) -1-cyclohexenylacetonitrile, α- (isopropylsulfonyloxyimino) -1-cyclohexenylacetonitrile , Α- (n-butylsulfonyloxyimino) -1-cyclohexenylacetonitrile, α- (methylsulfonyloxyimino) -phenylacetonitrile, α- (methylsulfonyloxyimino) -p-methoxyphenylacetonitrile, α- (trifluoro Methylsulfonyloxyimino) -phenylacetonitrile, α- (trifluoromethylsulfonyloxyimino) -p-methoxyphenylacetonitrile, α- (ethylsulfonyloxyimino) -p- Butoxy phenylacetonitrile, alpha-(propylsulfonyl oxyimino)-p-methylphenyl acetonitrile, alpha-like (methylsulfonyloxyimino)-p-bromophenyl acetonitrile.
Further, an oxime sulfonate-based acid generator disclosed in JP-A-9-208554 (paragraphs [0012] to [0014] [chemical formula 18] to [chemical formula 19]), WO2004 / 074242A2 (pages 65 to 85). The oxime sulfonate acid generators disclosed in Examples 1 to 40) of No. 1 can also be suitably used.
Moreover, the following can be illustrated as a suitable thing.

Among diazomethane acid generators, specific examples of bisalkyl or bisarylsulfonyldiazomethanes include bis (isopropylsulfonyl) diazomethane, bis (p-toluenesulfonyl) diazomethane, bis (1,1-dimethylethylsulfonyl) diazomethane, Examples include bis (cyclohexylsulfonyl) diazomethane, bis (2,4-dimethylphenylsulfonyl) diazomethane, and the like.
Further, diazomethane acid generators disclosed in JP-A-11-035551, JP-A-11-035552, and JP-A-11-035573 can also be suitably used.
Examples of poly (bissulfonyl) diazomethanes include 1,3-bis (phenylsulfonyldiazomethylsulfonyl) propane and 1,4-bis (phenylsulfonyldiazo) disclosed in JP-A-11-322707. Methylsulfonyl) butane, 1,6-bis (phenylsulfonyldiazomethylsulfonyl) hexane, 1,10-bis (phenylsulfonyldiazomethylsulfonyl) decane, 1,2-bis (cyclohexylsulfonyldiazomethylsulfonyl) ethane, 1,3 -Bis (cyclohexylsulfonyldiazomethylsulfonyl) propane, 1,6-bis (cyclohexylsulfonyldiazomethylsulfonyl) hexane, 1,10-bis (cyclohexylsulfonyldiazomethylsulfonyl) decane, etc. Door can be.

  As the component (B2), one type of acid generator may be used alone, or two or more types may be used in combination.

  Content of (B) component in the resist composition of this invention is 0.5-30 mass parts with respect to 100 mass parts of (A) component, Preferably it is 1-20 mass parts. By setting it within the above range, pattern formation is sufficiently performed. Moreover, since a uniform solution is obtained and storage stability becomes favorable, it is preferable.

<Optional component>
In the resist composition of the present invention, a nitrogen-containing organic compound (D) (hereinafter referred to as “component (D)”) is further blended as an optional component in order to improve the resist pattern shape, stability over time, etc. be able to.
Since a wide variety of components (D) have already been proposed, any known one may be used. Among them, aliphatic amines, particularly secondary aliphatic amines and tertiary aliphatic amines are used. preferable. An aliphatic amine is an amine having one or more aliphatic groups, and the aliphatic groups preferably have 1 to 12 carbon atoms.
Examples of the aliphatic amine include an amine (alkyl amine or alkyl alcohol amine) or a cyclic amine in which at least one hydrogen atom of ammonia NH ₃ is substituted with an alkyl group or hydroxyalkyl group having 12 or less carbon atoms.
Specific examples of alkylamines and alkyl alcohol amines include monoalkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine; diethylamine, di-n-propylamine, di- -Dialkylamines such as n-heptylamine, di-n-octylamine, dicyclohexylamine; trimethylamine, triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-hexylamine, tri-n-pentylamine , Tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decanylamine, tri-n-dodecylamine, etc .; diethanolamine, triethanolamine, diisopropanolamine Triisopropanolamine, di -n- octanol amines, alkyl alcohol amines tri -n- octanol amine. Among these, a trialkylamine in which 3 alkyl groups having 5 to 10 carbon atoms are bonded to a nitrogen atom is preferable, and tri-n-pentylamine is most preferable.
Examples of the cyclic amine include heterocyclic compounds containing a nitrogen atom as a hetero atom. The heterocyclic compound may be monocyclic (aliphatic monocyclic amine) or polycyclic (aliphatic polycyclic amine).
Specific examples of the aliphatic monocyclic amine include piperidine and piperazine.
As the aliphatic polycyclic amine, those having 6 to 10 carbon atoms are preferable. Specifically, 1,5-diazabicyclo [4.3.0] -5-nonene, 1,8-diazabicyclo [5. 4.0] -7-undecene, hexamethylenetetramine, 1,4-diazabicyclo [2.2.2] octane, and the like.
These may be used alone or in combination of two or more.
(D) component is normally used in 0.01-5.0 mass parts with respect to 100 mass parts of (A) component.

The resist composition of the present invention comprises, as optional components, an organic carboxylic acid, a phosphorus oxo acid, and derivatives thereof for the purpose of preventing sensitivity deterioration and improving the resist pattern shape, retention stability over time, and the like. At least one compound (E) selected from the group (hereinafter referred to as component (E)) can be contained.
As the organic carboxylic acid, for example, acetic acid, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, salicylic acid and the like are suitable.
Examples of phosphorus oxo acids and derivatives thereof include phosphoric acid, phosphonic acid, phosphinic acid and the like, and among these, phosphonic acid is particularly preferable.
Examples of the oxo acid derivative of phosphorus include esters in which the hydrogen atom of the oxo acid is substituted with a hydrocarbon group, and the hydrocarbon group includes an alkyl group having 1 to 5 carbon atoms and 6 to 6 carbon atoms. 15 aryl groups and the like.
Examples of phosphoric acid derivatives include phosphoric acid esters such as di-n-butyl phosphate and diphenyl phosphate.
Examples of phosphonic acid derivatives include phosphonic acid esters such as phosphonic acid dimethyl ester, phosphonic acid-di-n-butyl ester, phenylphosphonic acid, phosphonic acid diphenyl ester, and phosphonic acid dibenzyl ester.
Examples of the phosphinic acid derivatives include phosphinic acid esters such as phenylphosphinic acid.
(E) A component may be used individually by 1 type and may use 2 or more types together.
As the component (E), an organic carboxylic acid is preferable, and salicylic acid is particularly preferable.
(E) A component is used in the ratio of 0.01-5.0 mass parts per 100 mass parts of (A) component.

  The resist composition of the present invention may further contain, if desired, miscible additives such as an additional resin for improving the performance of the resist film, a surfactant for improving coatability, a dissolution inhibitor, Plasticizers, stabilizers, colorants, antihalation agents, dyes, and the like can be added and contained as appropriate.

<Organic solvent (S)>
The resist composition of the present invention can be produced by dissolving the material in an organic solvent (S) (hereinafter sometimes referred to as (S) component).
As the component (S), any component can be used as long as it can dissolve each component to be used to form a uniform solution. Conventionally, any one of known solvents for chemically amplified resists can be used. Two or more types can be appropriately selected and used.
For example, lactones such as γ-butyrolactone;
Ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-n-pentyl ketone, methyl isopentyl ketone, 2-heptanone;
Polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol;
Compounds having an ester bond such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, dipropylene glycol monoacetate, monomethyl ether, monoethyl ether, monopropyl of the polyhydric alcohols or the compound having an ester bond Derivatives of polyhydric alcohols such as ethers, monoalkyl ethers such as monobutyl ether or compounds having an ether bond such as monophenyl ether [in these, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME) Is preferred];
Cyclic ethers such as dioxane and esters such as methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, ethyl ethoxypropionate;
Aromatic organic solvents such as anisole, ethyl benzyl ether, cresyl methyl ether, diphenyl ether, dibenzyl ether, phenetol, butyl phenyl ether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, xylene, cymene, mesitylene, etc. be able to.
These organic solvents may be used independently and may be used as 2 or more types of mixed solvents.
Among these, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), and EL are preferable.
Moreover, the mixed solvent which mixed PGMEA and the polar solvent is also preferable. The blending ratio (mass ratio) may be appropriately determined in consideration of the compatibility between PGMEA and the polar solvent, preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. It is preferable to be within the range.
More specifically, when EL is blended as a polar solvent, the mass ratio of PGMEA: EL is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. Moreover, when mix | blending PGME as a polar solvent, the mass ratio of PGMEA: PGME becomes like this. Preferably it is 1: 9-9: 1, More preferably, it is 2: 8-8: 2, More preferably, it is 3: 7-7: 3.
In addition, as the component (S), a mixed solvent of at least one selected from PGMEA and EL and γ-butyrolactone is also preferable. In this case, the mixing ratio of the former and the latter is preferably 70:30 to 95: 5.
The amount of the component (S) used is not particularly limited, but is a concentration that can be applied to a substrate or the like, and is appropriately set according to the coating film thickness. In general, the solid content concentration of the resist composition is 2 -20% by mass, preferably 5-15% by mass.

≪Resist pattern formation method≫
The resist pattern forming method of the present invention includes a step of forming a resist film on a support using the resist composition of the present invention, a step of exposing the resist film, and developing the resist film to form a resist pattern The process of carrying out is included.
The resist pattern forming method of the present invention can be performed, for example, as follows.
That is, first, the resist composition of the present invention is applied onto a support with a spinner or the like, and prebaked (post-apply bake (PAB)) for 40 to 120 seconds, preferably 60 to 150 ° C. under a temperature condition of 80 to 150 ° C. This is applied for 90 seconds, and this is selectively exposed to ArF excimer laser light through a desired mask pattern using, for example, an ArF exposure apparatus, and then subjected to PEB (post-exposure heating) at a temperature of 80 to 150 ° C. for 40 to 40 ° C. It is applied for 120 seconds, preferably 60 to 90 seconds. Subsequently, this is developed using an alkali developer, for example, an aqueous solution of 0.1 to 10% by mass of tetramethylammonium hydroxide (TMAH), preferably rinsed with pure water and dried. In some cases, a baking process (post-bake) may be performed after the development process. In this way, a resist pattern faithful to the mask pattern can be obtained.

The support is not particularly limited, and a conventionally known one can be used, and examples thereof include a substrate for electronic components and a substrate on which a predetermined wiring pattern is formed. More specifically, a silicon substrate, a metal substrate such as copper, chromium, iron, and aluminum, a glass substrate, and the like can be given. As a material for the wiring pattern, for example, copper, aluminum, nickel, gold or the like can be used.
Further, the support may be a substrate in which an inorganic and / or organic film is provided on the above-described substrate. An inorganic antireflection film (inorganic BARC) is an example of the inorganic film. Examples of the organic film include an organic antireflection film (organic BARC).

The wavelength used for exposure is not particularly limited, and ArF excimer laser, KrF excimer laser, F ₂ excimer laser, EUV (extreme ultraviolet), VUV (vacuum ultraviolet), EB (electron beam), X-ray, soft X-ray, etc. Can be done using radiation. The resist composition is effective for KrF excimer laser, ArF excimer laser, EB or EUV, particularly ArF excimer laser.

The exposure of the resist film may be normal exposure (dry exposure) performed in an inert gas such as air or nitrogen, or may be immersion exposure.
In immersion exposure, as described above, the portion between the lens, which has been conventionally filled with an inert gas such as air or nitrogen, and the resist film on the wafer is refracted larger than the refractive index of air. The exposure is performed in a state filled with a solvent having a high rate (immersion medium).
More specifically, the immersion exposure is a solvent (immersion medium) having a refractive index larger than the refractive index of air between the resist film obtained as described above and the lowermost lens of the exposure apparatus. And in that state, exposure can be performed through a desired mask pattern (immersion exposure).
As the immersion medium, a solvent having a refractive index larger than the refractive index of air and smaller than the refractive index of the resist film exposed by the immersion exposure is preferable. The refractive index of such a solvent is not particularly limited as long as it is within the above range.
Examples of the solvent having a refractive index larger than the refractive index of air and smaller than the refractive index of the resist film include water, a fluorine-based inert liquid, a silicon-based solvent, and a hydrocarbon-based solvent.
Specific examples of the fluorine-based inert liquid include a fluorine-based compound such as C ₃ HCl ₂ F ₅ , C ₄ F ₉ OCH ₃ , C ₄ F ₉ OC ₂ H ₅ , and C ₅ H ₃ F ₇ as a main component. Examples thereof include liquids, and those having a boiling point of 70 to 180 ° C are preferable, and those having a boiling point of 80 to 160 ° C are more preferable. It is preferable that the fluorine-based inert liquid has a boiling point in the above range since the medium used for immersion can be removed by a simple method after the exposure is completed.
As the fluorine-based inert liquid, a perfluoroalkyl compound in which all hydrogen atoms of the alkyl group are substituted with fluorine atoms is particularly preferable. Specific examples of the perfluoroalkyl compound include a perfluoroalkyl ether compound and a perfluoroalkylamine compound.
More specifically, examples of the perfluoroalkyl ether compound include perfluoro (2-butyl-tetrahydrofuran) (boiling point: 102 ° C.). Examples of the perfluoroalkylamine compound include perfluorotributylamine ( Boiling point of 174 ° C.).

The resist composition of the present invention is a novel one that has not been conventionally known.
The resist composition of the present invention also has good lithography properties such as sensitivity and resolution, and can form a fine resist pattern having a line width of a line and space pattern of 120 nm or less, for example. In addition, when a resist pattern is formed using a conventional resist composition, the resist pattern shape tends to be poor, such as the bottom of the resist pattern spreading out (bottoming) at the substrate interface, resulting in reduced rectangularity. However, according to the resist composition of the present invention, a resist pattern with reduced tailing can be formed.
In addition, the component (B1) used in the resist composition of the present invention is 200 nm or less, particularly around 193 nm, compared to an acid generator, such as triphenylsulfonium salt, conventionally used in chemically amplified resist compositions. High transparency to light with a wavelength of. Therefore, in the resist composition of the present invention, it is possible to increase the blending amount of component (B) as compared with the conventional resist composition.
The component (B1) is also excellent in acid generation efficiency at the time of exposure. By containing the component (B1) as the component (B), the resist composition of the present invention has good sensitivity. .
It is considered that these effects are mainly influenced by the structure of the cation moiety of the component (B1).
Further, it is considered that the component (B1) has an anion portion having a structure in which a functional group of “R ¹ —O— [CO] _n —” is introduced into the skeleton of Y ¹ —SO ₃ ^—. It is done. That is, the anion portion having such a structure is a conventional acid generator such as nonafluorobutanesulfonate, although Y ¹ has a relatively small number of carbon atoms of an alkylene group which may be substituted with 1 to 4 carbon atoms. Compared to the anion portion, excessive diffusion of the acid after exposure is suppressed. Therefore, it is considered that a resist pattern with good lithography characteristics can be formed.
In addition, the component (B1) is such that Y ¹ is an alkyl chain of an alkylene group having 1 to 4 carbon atoms which may be fluorine-substituted, and a perfluoroalkyl chain having 6 to 10 carbon atoms is hardly decomposable. It is safer in terms of handling in consideration of bioaccumulation.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited by these examples.
[Example 1]
5 ml of tetrahydrofuran was added to 1.0 g of allyloxytetrafluoroethanesulfonyl fluoride, and an aqueous solution in which 0.20 g of lithium hydroxide was dissolved in 2.8 ml of pure water was dropped into the solution in a water bath. Stir. It was confirmed that all of the sulfonyl fluoride groups were converted to lithium sulfonate due to the absence of ¹⁹ F-NMR absorption at −217.8 ppm by —SO ₂ F. Thereafter, the reaction solution was concentrated and dried to obtain a white viscous solid. The obtained crude product was dissolved in 3.35 ml of acetone, filtered to remove LiF as a byproduct, and the filtrate was concentrated to give a compound represented by the following chemical formula (1-1) (1- 1) 0.58 g was obtained.

Next, 10.00 g of diphenyliodonium methanesulfonate was dissolved in 50.00 g of water, and 6.81 g of the compound (1-1) was added thereto, followed by stirring at room temperature for 1 hour. After completion of the reaction, 68.9 g of ethyl acetate was added to perform extraction operation, and after separation, the organic layer was washed 5 times with 34.5 g of pure water. After washing, the obtained organic layer was concentrated to obtain 6.70 g of the target compound.
The obtained compound (hereinafter referred to as compound (I-11)) was analyzed by ¹ H-NMR and ¹⁹ F-NMR. The results are shown below.
¹ H-NMR (solvent: CDCl ₃ , 400 MHz): δ (ppm) = 7.94 (d, 4H (H ^a )), 7.44 (d, 2H (H ^c )), 7.30 (t, 4H (H ^b )), 5.71-5.80 (m, 1H (H ^e )), 5.06-5.29 (m, 2H (H ^d )), 4.34 (d, 2H (H ^f )).
¹⁹ F-NMR (solvent: CDCl ₃ , 376 MHz): δ (ppm) = − 83.6, −115.7.
From the results shown above, it was confirmed that the compound (I-11) had a structure shown below.

3.93 g of compound (I-11), 0.7745 g of pentamethylene sulfide and 0.060 g of copper (II) benzoate were dissolved in 5.90 g of chlorobenzene and reacted at 100 ° C. for 1 hour. After completion of the reaction, the reaction solution was concentrated to dryness and dissolved in 26.2 g of dichloromethane. The dichloromethane solution was washed with water and concentrated to obtain 0.84 g of the target compound.
The obtained compound (hereinafter, referred to as compound (b1-11)) was analyzed by ¹ H-NMR and ¹⁹ F-NMR. The results are shown below.
¹ H-NMR (solvent: CDCl ₃ , 400 MHz): δ (ppm) = 8.10 (d, 2H (H ^c )), 7.59-7.69 (m, 3H (H ^a + H ^b )), 5.86-5.96 (m, 1H (H ^h )), 5.19-5.42 (m, 2H (H ^g )), 4.50 (d, 2H (H ⁱ )), 3.68 ^{-3.98 (m, 4H (H d} )), 1.85-2.30 (m, 6H (H e + H f)).
¹⁹ F-NMR (solvent: CDCl ₃ , 376 MHz): δ (ppm) = − 79.9, −112.2.
From the results above, it was confirmed that the compound (b1-11) had a structure shown below.

[Example 2]
6.7 ml of 1 tetrahydrofuran was added to 5.0 g of 2-naphthylmethyloxytetrafluoroethanesulfonyl fluoride, and an aqueous solution obtained by dissolving 0.98 g of lithium hydroxide in 13.6 ml of pure water was added dropwise to the solution in an ice bath. . Then, it stirred in the ice bath. It was confirmed that all of the sulfonyl fluoride groups were converted to lithium sulfonate due to the absence of ¹⁹ F-NMR absorption at −217.6 ppm by —SO ₂ F. Thereafter, the reaction solution was concentrated and dried to obtain a white viscous solid. The obtained crude product was dissolved in 14.2 ml of acetone, filtered to remove LiF as a by-product, and the filtrate was concentrated to give a compound (1) represented by the following chemical formula (1-2). -2) 5.50 g was obtained.

Next, 7.64 g of diphenyliodonium methanesulfonate was dissolved in 38.02 g of water, 7.30 g of the compound (1-2) was added thereto, and the mixture was stirred at room temperature for 1 hour. After completion of the reaction, 38.02 g of ethyl acetate was added to perform extraction operation, and after liquid separation, the organic layer was washed 5 times with 38.02 g of pure water. After washing, the organic layer was crystallized with hexane, and the obtained powder was dried under reduced pressure to obtain 10.87 g of the target compound.
The obtained compound (hereinafter referred to as compound (I-12)) was analyzed by ¹ H-NMR and ¹⁹ F-NMR. The results are shown below.
¹ H-NMR (solvent: CDCl ₃ , 400 MHz): δ (ppm) = 7.99-8.01 (d, 4H (H ^a )), 7.59 (s, 1 H (H ^d )), 7. 80-7.83 (m, 3H (Phenyl + Naptyl)), 7.39-7.58 (m, 9H (Phenyl + Naptyl)), 5.20 (s, 2H (H ^e )).
¹⁹ F-NMR (solvent: CDCl ₃ , 376 MHz): δ (ppm) = − 79.0, −111.6.
From the results above, it was confirmed that the compound (I-12) had a structure shown below.

8.00 g of compound (I-12), 1.32 g of pentamethylene sulfide and 0.10 g of copper (II) benzoate were dissolved in 12.00 g of chlorobenzene and reacted at 100 ° C. for 1 hour. After completion of the reaction, the reaction solution was concentrated to dryness and dissolved in 33.40 g of dichloromethane. The dichloromethane solution was washed with water and concentrated to obtain 0.53 g of the target compound.
The obtained compound (hereinafter referred to as compound (b1-12)) was analyzed by ¹ H-NMR and ¹⁹ F-NMR. The results are shown below.
¹ H-NMR (solvent: CDCl ₃ , 400 MHz): δ (ppm) = 7.93-7.95 (d, 2H (H ^c )), 7.85 (s, 1 H (H ^g )), 7. 77-7.81 (m, 3H (Phenyl + Naptyl)), 7.46-7.56 (m, 6H (Phenyl + Naptyl)), 5.21 (s, 2H (H ^h )), 3.48-3.79 ^{(m, 4H (H d)} ), 1.68-2.13 (m, 6H (H e + H f)).
¹⁹ F-NMR (solvent: CDCl ₃ , 376 MHz): δ (ppm) = − 84.0, −116.5.
From the results above, it was confirmed that the compound (b1-12) had a structure shown below.

[Comparative Example 1]
0.28 g of triphenylsulfonium bromide was dissolved in 5.0 ml of pure water, 0.17 g of the compound (1-1) obtained in the same manner as in Example 1 was added to the solution, and the mixture was stirred at room temperature for 14 hours. Thereafter, 10 ml of dichloromethane was added and stirred, and the organic phase was separated and taken out. Further, the organic phase was washed with 5.0 ml of pure water and then separated to take out the organic phase. The extracted organic phase was concentrated and dried to obtain 0.16 g of the target compound.

The obtained compound (hereinafter referred to as compound (b2-11)) was analyzed by ¹ H-NMR and ¹⁹ F-NMR. The results are shown below.
¹ H-NMR (acetone-d6, 400 MHz): δ (ppm) = 8.30-7.60 (m, 15H (H ^a )), 5.91 (m, 1 H (H ^b )), 5.47 ^{(d, 1H (H c)} ), 5.16 (d, 1H (H d)), 4.48 (d, 2H (H e)).
¹⁹ F-NMR (acetone-d6, 376 MHz): δ (ppm) = 79.8, 112.1.
From the above results, it was confirmed that the compound had the structure shown below.

[Comparative Example 2]
After dissolving 6.99 g of triphenylsulfonium bromide in 125 ml of pure water, 5.50 g of the compound (1-2) obtained in the same manner as in Example 2 was added to the solution, and the mixture was stirred at room temperature for 19 hours. 125 g of dichloromethane was added and stirred, and the organic phase was separated and removed. Further, the organic phase was washed with 40 ml of pure water and then separated to take out the organic phase. The extracted organic phase was concentrated and dried to obtain 7.09 g of the target compound (yield: 75.2%).

The obtained compound (hereinafter referred to as compound (b2-12)) was analyzed by ¹ H-NMR and ¹⁹ F-NMR. The results are shown below.
¹ H-NMR (acetone-d6, 400 MHz): δ (ppm) = 8.01 to 7.47 (m, 22H (H ^a )), 5.23 (s, 2H (H ^b )).
¹⁹ F-NMR (acetone-d6, 376 MHz): δ (ppm) = 79.2, 111.8.
From the results above, it was confirmed that the compound (b2-12) had a structure shown below.

[Example 3]
5.00 g of 1- (2-oxo-2-phenylethyl) tetrahydrothiophenium bromide was dissolved in 25 g of pure water, and 6.6 g of the compound (1-2) obtained in the same manner as in Example 2 was added thereto. The mixture was added and stirred at room temperature for 2 hours. Thereafter, 25.0 g of dichloromethane was added, the dichloromethane layer was separated, washed with dilute hydrochloric acid and water, and 250.0 g of n-hexane was added to the dichloromethane layer to obtain 8.5 g of the target compound as a white solid. .

The obtained compound (hereinafter referred to as compound (b1-13)) was analyzed by ¹ H-NMR and ¹⁹ F-NMR. The results are shown below. From this result, it was confirmed that the compound (b1-13) had a structure represented by the above chemical formula.
¹ H-NMR (DMSO-d6, 400 MHz): δ (ppm) = 7.88-8.01 (m, 6H (Ar)), 7.75 (t, 1H (Ar)), 7.61 (t , 2H (Ar)), 7.52-7.54 (m, 3H (Ar)), 5.34 (s, 2H (CH 2)), 5.20 (s, 2H (CH 2)), 3 _{.48-3.59 (m, 4H (CH 2} -CH 2)), 2.17-2.26 (m, 4H (CH 2 -CH 2)).
¹⁹ F-NMR (acetone-d6, 376 MHz): δ (ppm) = − 79.6, −111.9.

[Solvent solubility evaluation]
Compounds (b1-11), (b1-12), (b1-13), (b2-11), (b2-12) obtained in Examples 1 to 3 and Comparative Examples 1 and 2, respectively, and About the compound (b2-13) represented by a formula (b2-13), the solvent solubility was evaluated in the following procedure.
Each compound is added to propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), and ethyl lactate (EL), which are common resist solvents, and added at 25 ° C. for 30 minutes. did. After stirring, the concentration (% by mass) at which each compound was completely dissolved was measured. The results are shown in Table 1.

As shown in Table 1, all of the compounds (b1-11) and (b1-12) and the compound (b2-13) according to the present invention have extremely high solubility in PGMEA, PGME, and EL.
On the other hand, the compound (b2-11) had relatively good solubility in PGMEA and EL, but poor in solubility in PGMEA. Compound (b2-12) was poorly soluble in any solvent. Moreover, about the compound (b1-13) which changed only the cation part from the compound (b2-12), the solubility with respect to PGMEA improved.

[Examples 4 to 6, Comparative Example 3]
Each component shown in Table 2 was mixed and dissolved to prepare a positive resist composition.

In Table 2, the numerical value in [] shows a compounding quantity (part by mass). Moreover, the symbol in Table 2 shows the following, respectively. In addition, the compounding quantity of (B) component is equimolar amount.
(A) -1: Mw = 7000 and Mw / Mn = 1.8 represented by the following chemical formula (A) -1 (wherein l / m / n = 45/35/20 (molar ratio)) Polymer.
(B) -1: Compound (b1-11) obtained in Example 1.
(B) -2: Compound (b1-12) obtained in Example 2.
(B) -3: Compound (b1-13) obtained in Example 3.
(B) -4: Compound (b2-13) represented by formula (b2-13).
(D) -1: tri-n-pentylamine.
(E) -1: salicylic acid.
(S) -1: γ-butyrolactone.
(S) -1: PGMEA / PGME = 6/4 (mass ratio) mixed solvent.

Using the obtained resist composition, a resist pattern was formed by the following procedure, and the lithography characteristics were evaluated.
[Resolution and sensitivity]
An organic antireflection film composition “ARC29A” (trade name, manufactured by Brewer Science Co., Ltd.) is applied onto an 8-inch silicon wafer using a spinner, and baked at 205 ° C. for 60 seconds on a hot plate and dried. Thus, an organic antireflection film having a film thickness of 82 nm was formed. By applying the resist composition obtained above onto the antireflection film using a spinner, performing pre-baking (PAB) treatment at 110 ° C. for 60 seconds on a hot plate, and drying, A resist film having a thickness of 150 nm was formed.
Next, an ArF excimer laser (193 nm) was passed through a mask pattern (6% halftone) using an ArF exposure apparatus NSR-S302 (Nikon Corporation; NA (numerical aperture) = 0.60, 2/3 annular illumination). Selectively irradiated. Then, post-exposure heating (PEB) treatment is performed at 110 ° C. for 60 seconds, and further development is performed at 23 ° C. with an aqueous 2.38 mass% tetramethylammonium hydroxide (TMAH) solution for 30 seconds, and then 30 Water rinsing was performed using pure water for 2 seconds, and then shaken off and dried.
As a result, in each of the examples, a line and space (1: 1) resist pattern (L / S pattern) having a line width of 120 nm and a pitch of 240 nm was formed.
At this time, the optimum exposure dose Eop (mJ / cm ² ), that is, the sensitivity at which an L / S pattern having a line width of 120 nm and a pitch of 240 nm is formed was determined. The results are shown in Table 3.

[Line width roughness (LWR)]
In each L / S pattern formed by the Eop, the line width was measured at five locations in the longitudinal direction of the line with a length measuring SEM (scanning electron microscope, trade name: S-9220, manufactured by Hitachi, Ltd.). From the results, a standard deviation (s) triple value (3 s) was calculated as a measure of LWR. The results are shown in Table 3. The smaller the value of 3s, the smaller the roughness of the line width, which means that a more uniform width L / S pattern was obtained.

  As shown in Table 3, the resist compositions of Examples 4 to 6 had good LWR. On the other hand, the resist composition of Comparative Example 3 had a poor LWR.

Claims (11)

The compound represented by the following general formula (b1-1).

[Wherein, R ¹ is an aryl group or an alkyl group which may have a substituent, R ³ is a hydrogen atom or an alkyl group, n1 is 0 or 1, and n1 is 1, R ¹ and R ³ may be bonded to each other to form a ^3- to 7-membered ring with the carbon atom to which R ¹ is bonded and the carbon atom to which R ³ is bonded; It is a divalent group that forms a ring having a 3- to 7-membered ring structure with a bonded sulfur atom, and the ring may have a substituent, and R ² represents R ⁵³ —R ⁵⁴ — (wherein R ⁵³ is an alkenyl group or aryl group having 2 to 10 carbon atoms, R ⁵⁴ is a linear or branched alkylene group having 1 to 5 carbon atoms, and n is 0 Y ¹ is an optionally substituted alkylene group having 1 to 4 carbon atoms. ] A compound represented by the following general formula (I), a compound represented by the following general formula (II), and a copper catalyst are reacted to obtain a compound represented by the following general formula (b1-1-1). The manufacturing method of the compound represented by general formula (b1-1-1) including a process.

[Wherein, A is a divalent group that forms a ring with a 3- to 7-membered ring structure together with the sulfur atom to which A is bonded, and the ring may have a substituent, and R ² represents R ⁵³ —R ⁵⁴ — (wherein R ⁵³ is an alkenyl group or aryl group having 2 to 10 carbon atoms, and R ⁵⁴ is a linear or branched alkylene group having 1 to 5 carbon atoms). A group represented by the formula, n is 0, Y ¹ is an optionally substituted alkylene group having 1 to 4 carbon atoms, and each R ¹ independently has a substituent. A good aryl or alkyl group. ] The compound represented by the following general formula (I).

[Wherein R ² is R ⁵³ —R ⁵⁴ — (wherein R ⁵³ is an alkenyl group or aryl group having 2 to 10 carbon atoms, and R ⁵⁴ is a linear or branched chain having 1 to 5 carbon atoms. And n 1 is 0, Y ¹ is an optionally substituted alkylene group having 1 to 4 carbon atoms, and each R ¹ is independently An aryl group or an alkyl group which may have a substituent. ]   An acid generator comprising the compound according to claim 1. A resist composition containing a base material component (A) whose solubility in an alkaline developer is changed by the action of an acid, and an acid generator component (B) that generates an acid upon exposure,
The resist composition, wherein the acid generator component (B) includes an acid generator (B1) composed of a compound represented by the following general formula (b1-1).

[Wherein, R ¹ is an aryl group or an alkyl group which may have a substituent, R ³ is a hydrogen atom or an alkyl group, n1 is 0 or 1, and n1 is 1, R ¹ and R ³ may be bonded to each other to form a ^3- to 7-membered ring with the carbon atom to which R ¹ is bonded and the carbon atom to which R ³ is bonded; It is a divalent group that forms a ring having a 3- to 7-membered ring structure with a bonded sulfur atom, and the ring may have a substituent, and R ² represents R ⁵³ —R ⁵⁴ — (wherein R ⁵³ is an alkenyl group or aryl group having 2 to 10 carbon atoms, R ⁵⁴ is a linear or branched alkylene group having 1 to 5 carbon atoms, and n is 0 Y ¹ is an optionally substituted alkylene group having 1 to 4 carbon atoms. ]   The resist composition according to claim 5, wherein the base material component (A) is a base material component whose solubility in an alkaline developer is increased by the action of an acid.   The base material component (A) contains a resin component (A1) whose solubility in an alkaline developer is increased by the action of an acid, and the resin component (A1) contains an acid dissociable, dissolution inhibiting group. The resist composition according to claim 6, comprising a structural unit (a1) derived from   The resist composition according to claim 7, wherein the resin component (A1) further has a structural unit (a2) derived from an acrylate ester containing a lactone-containing cyclic group.   The resist composition according to claim 7 or 8, wherein the resin component (A1) further has a structural unit (a3) derived from an acrylate ester containing a polar group-containing aliphatic hydrocarbon group.   The resist composition as described in any one of Claims 5-9 containing a nitrogen-containing organic compound (D).   A step of forming a resist film on a support using the resist composition according to claim 5, a step of exposing the resist film, and an alkali development of the resist film to form a resist pattern A resist pattern forming method including a forming step.