JP6768370B2 - Resist composition, resist pattern forming method and compound - Google Patents

Description

The present invention relates to resist compositions, resist pattern forming methods and compounds.

In the lithography technology, for example, a resist film made of a resist material is formed on a substrate, the resist film is selectively exposed, and a development process is performed to form a resist pattern having a predetermined shape on the resist film. The process of performing is performed. A resist material whose exposed portion of the resist film changes to a characteristic of being soluble in a developing solution is called a positive type, and a resist material whose exposed portion changes to a characteristic of not being dissolved in a developing solution is called a negative type.
In recent years, in the manufacture of semiconductor elements and liquid crystal display elements, pattern miniaturization is rapidly progressing due to advances in lithography technology.
As a miniaturization method, generally, the wavelength of the exposure light source is shortened (energy is increased). Specifically, in the past, ultraviolet rays typified by g-rays and i-rays were used, but nowadays, mass production of semiconductor devices using KrF excimer lasers and ArF excimer lasers has started. In addition, EUV (extreme ultraviolet), EB (electron beam), X-ray, etc., which have a shorter wavelength (higher energy) than these excimer lasers, are also being studied.

Further, at present, in EUV lithography and EB lithography, as a resist material, it is excellent in lithography characteristics such as sensitivity to EUV and EB and resolution capable of forming a target fine resist pattern. , The chemically amplified resist proposed for the ArF excimer laser and the like is generally used. In particular, chemically amplified resists containing an acrylic resin as a base resin are said to be excellent in their lithography characteristics.

In EUV lithography, it is required to achieve both high sensitivity of the resist and the shape of the resist pattern. For example, Patent Document 1 discloses a resist composition containing an acid generator having a specific structure and having a high reduction potential.

Japanese Patent No. 4083035

It is also being considered to increase the amount of the acid generator in the resist composition in order to further increase the sensitivity of the resist. However, the conventional acid generator has a problem that when the blending amount is increased, the film of the resist pattern is reduced and the lithography characteristics are deteriorated.

The present invention has been made in view of the above circumstances, and is a resist composition having good lithography characteristics such as sensitivity and capable of forming a resist pattern having a good shape, a resist pattern forming method using the resist composition, and the like. An object of the present invention is to provide a compound used as an acid generator component of the resist composition.

The first aspect of the present invention is a resist composition in which an acid is generated by exposure and the solubility in a developing solution is changed by the action of the acid, and contains an acid generator component (B) that generates an acid by exposure. The acid generator component (B) is a resist composition containing a compound (B1) represented by the following general formula (b1).

［式中、Ｗ^ｂは、置換基を有していてもよい炭化水素基である。Ｒ^ｂ１〜Ｒ^ｂ８は、それぞれ独立に、電子吸引性基又は水素原子である。但し、Ｒ^ｂ１〜Ｒ^ｂ８の内の少なくとも１つは電子吸引性基である。Ｒ^ｓ１〜Ｒ^ｓ４は、それぞれ独立に、置換基である。ｎ_ｂ１〜ｎ_ｂ４は、それぞれ独立に、０〜３の整数である。Ｚ^ｎ−は、ｎ価のアニオンであり、ｎは１以上の整数である。］

[In the formula, W ^b is a hydrocarbon group which may have a substituent. R ^{b1 to} R ^b8 are each independently an electron-withdrawing group or a hydrogen atom. However, at least one of R ^{b1 to} R ^b8 is an electron-withdrawing group. R ^{s1 to} R ^s4 are independent substituents. n _{b1 to} n _b4 are independently integers of 0 to 3. Z ⁿ⁻ is an n-valent anion, and n is an integer of 1 or more. ]

A second aspect of the present invention is a step of forming a resist film on a support using the resist composition according to the first aspect, a step of exposing the resist film, and a step of exposing the resist film after the exposure. This is a resist pattern forming method including a step of developing a resist pattern.

A third aspect of the present invention is a compound represented by the following general formula (b1).

［式中、Ｗ^ｂは、置換基を有していてもよい炭化水素基である。Ｒ^ｂ１〜Ｒ^ｂ８は、それぞれ独立に、電子吸引性基又は水素原子である。但し、Ｒ^ｂ１〜Ｒ^ｂ８の内の少なくとも１つは電子吸引性基である。Ｒ^ｓ１〜Ｒ^ｓ４は、それぞれ独立に、置換基である。ｎ_ｂ１〜ｎ_ｂ４は、それぞれ独立に、０〜３の整数である。Ｚ^ｎ−は、ｎ価のアニオンであり、ｎは１以上の整数である。］

[In the formula, W ^b is a hydrocarbon group which may have a substituent. R ^{b1 to} R ^b8 are each independently an electron-withdrawing group or a hydrogen atom. However, at least one of R ^{b1 to} R ^b8 is an electron-withdrawing group. R ^{s1 to} R ^s4 are independent substituents. n _{b1 to} n _b4 are independently integers of 0 to 3. Z ⁿ⁻ is an n-valent anion, and n is an integer of 1 or more. ]

As used herein and in the claims, "aliphatic" is defined as a relative concept to aromatics, meaning groups, compounds, etc. that do not have aromaticity.
Unless otherwise specified, the "alkyl group" shall include linear, branched and cyclic monovalent saturated hydrocarbon groups.
Unless otherwise specified, the "alkylene group" shall include linear, branched and cyclic divalent saturated hydrocarbon groups. The same applies to the alkyl group in the alkoxy group.
The "alkyl halide group" is a group in which a part or all of the hydrogen atom of the alkyl group is substituted with a halogen atom, and examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.
The "fluorinated alkyl group" or "fluorinated alkylene group" refers to a group in which a part or all of hydrogen atoms of the alkyl group or the alkylene group is substituted with a fluorine atom.
The “constituent unit” means a monomer unit (monomer unit) constituting a polymer compound (resin, polymer, copolymer).
The “constituent unit derived from the acrylic acid ester” means a structural unit formed by cleaving the ethylenic double bond of the acrylic acid ester.
The "acrylic acid ester" is a compound in which the hydrogen atom at the terminal of the carboxy group of acrylic acid (CH ₂ = CH-COOH) is replaced with an organic group.
In the acrylic acid ester, the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent. The substituent (R ^α ) that replaces the hydrogen atom bonded to the carbon atom at the α-position is an atom or group other than the hydrogen atom, for example, an alkyl group having 1 to 5 carbon atoms and a halogenation having 1 to 5 carbon atoms. Examples thereof include an alkyl group and a hydroxyalkyl group. The carbon atom at the α-position of the acrylic acid ester is a carbon atom to which a carbonyl group is bonded unless otherwise specified.
Hereinafter, an acrylic acid ester in which a hydrogen atom bonded to a carbon atom at the α-position is substituted with a substituent may be referred to as an α-substituted acrylic acid ester. Further, the acrylic acid ester and the α-substituted acrylic acid ester may be collectively referred to as “(α-substituted) acrylic acid ester”.
The “constituent unit derived from the hydroxystyrene derivative” means a structural unit formed by cleaving the ethylenic double bond of hydroxystyrene or the hydroxystyrene derivative.
The term "hydroxystyrene derivative" is a concept including a hydrogen atom at the α-position of hydroxystyrene substituted with another substituent such as an alkyl group or an alkyl halide group, and derivatives thereof. As those derivatives, the hydrogen atom at the α-position may be substituted with a substituent, the hydrogen atom of the hydroxyl group of hydroxystyrene is substituted with an organic group, or the hydrogen atom at the α-position is substituted with a substituent. Examples thereof include a good hydroxystyrene benzene ring to which a substituent other than a hydroxyl group is bonded. The α-position (carbon atom at the α-position) refers to a carbon atom to which a benzene ring is bonded unless otherwise specified.
Examples of the substituent substituting the hydrogen atom at the α-position of hydroxystyrene include the same as those mentioned as the substituent at the α-position in the α-substituted acrylic acid ester.
"Constituent unit derived from vinyl benzoic acid or vinyl benzoic acid derivative" means a structural unit formed by cleavage of an ethylenic double bond of vinyl benzoic acid or a vinyl benzoic acid derivative.
The "vinyl benzoic acid derivative" is a concept including those in which the hydrogen atom at the α-position of vinyl benzoic acid is substituted with another substituent such as an alkyl group or an alkyl halide group, and derivatives thereof. As those derivatives, the hydrogen atom at the α-position may be substituted with a substituent, the hydrogen atom of the carboxy group of vinyl benzoic acid is substituted with an organic group, and the hydrogen atom at the α-position is substituted with a substituent. Examples thereof include a vinyl benzoic acid having a benzene ring bonded to a substituent other than a hydroxyl group and a carboxy group. The α-position (carbon atom at the α-position) refers to a carbon atom to which a benzene ring is bonded unless otherwise specified.
The "styrene derivative" means that the hydrogen atom at the α-position of styrene is substituted with another substituent such as an alkyl group or an alkyl halide group.
“Constituent unit derived from styrene” and “constituent unit derived from a styrene derivative” mean a structural unit formed by cleaving an ethylenic double bond of styrene or a styrene derivative.
The alkyl group as the substituent at the α-position is preferably a linear or branched alkyl group, and specifically, an alkyl group having 1 to 5 carbon atoms (methyl group, ethyl group, propyl group, isopropyl group). , N-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group) and the like.
Further, the alkyl halide group as the substituent at the α-position is specifically a group in which a part or all of the hydrogen atom of the above-mentioned "alkyl group as the substituent at the α-position" is substituted with a halogen atom. Be done. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like, and a fluorine atom is particularly preferable.
Specific examples of the hydroxyalkyl group as the substituent at the α-position include a group in which a part or all of the hydrogen atom of the above-mentioned "alkyl group as the substituent at the α-position" is substituted with a hydroxyl group. The number of hydroxyl groups in the hydroxyalkyl group is preferably 1 to 5, and most preferably 1.
When it is described that "it may have a substituent", when the hydrogen atom (-H) is replaced with a monovalent group and when the methylene group (-CH _2- ) is replaced with a divalent group. Including both.
"Exposure" is a concept that includes general irradiation of radiation.

According to the present invention, a resist composition having good lithography characteristics such as sensitivity and capable of forming a resist pattern having a good shape, a resist pattern forming method using the resist composition, and an acid generator of the resist composition. A compound used as an ingredient can be provided.

≪Resist composition≫
The resist composition of the present invention is a resist composition that generates an acid by exposure and changes its solubility in a developing solution by the action of the acid, and is an acid generator component (B) that generates an acid by exposure (hereinafter, "" (B) component "), and the acid generator component (B) contains a compound (B1) represented by the following general formula (b1) (hereinafter referred to as" (B1) component "). It is characterized by.

［式中、Ｗ^ｂは、置換基を有していてもよい炭化水素基である。ｎ_ｂｗは０〜４の整数である。Ｒ^ｂ１〜Ｒ^ｂ８は、それぞれ独立に、電子吸引性基又は水素原子である。但し、Ｒ^ｂ１〜Ｒ^ｂ８の内の少なくとも１つは電子吸引性基である。Ｒ^ｓ１〜Ｒ^ｓ４は、それぞれ独立に、置換基である。ｎ_ｂ１〜ｎ_ｂ４は、それぞれ独立に、０〜３の整数である。Ｚ^ｎ−は、ｎ価のアニオンであり、ｎは１以上の整数である。］

[In the formula, W ^b is a hydrocarbon group which may have a substituent. n _bw is an integer from 0 to 4. R ^{b1 to} R ^b8 are each independently an electron-withdrawing group or a hydrogen atom. However, at least one of R ^{b1 to} R ^b8 is an electron-withdrawing group. R ^{s1 to} R ^s4 are independent substituents. n _{b1 to} n _b4 are independently integers of 0 to 3. Z ⁿ⁻ is an n-valent anion, and n is an integer of 1 or more. ]

In the general formula (b1), W ^b is a hydrocarbon group which may have a substituent. The hydrocarbon group of W ^b may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. Aliphatic hydrocarbon groups mean hydrocarbon groups that do not have aromaticity.

· Divalent aliphatic hydrocarbon group as the hydrocarbon group in the aliphatic hydrocarbon radical W ^b may be saturated, may be unsaturated, but is preferably saturated.
More specific examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group having a ring in its structure, and the like.

Linear or branched aliphatic hydrocarbon group The linear aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, and 1 to 4 carbon atoms. More preferably, 1 to 3 are most preferable.
As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specifically, a methylene group [−CH ₂ −], an ethylene group [− (CH ₂ ) ₂ −], and a trimethylene group [ − (CH ₂ ) ₃ −], tetramethylene group [− (CH ₂ ) ₄ −], pentamethylene group [− (CH ₂ ) ₅ −] and the like can be mentioned.
The branched-chain aliphatic hydrocarbon group preferably has 3 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, still more preferably 3 or 4, and most preferably 3.
As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, and specifically, −CH (CH ₃ ) −, −CH (CH ₂ CH ₃ ) −, −C (CH ₃ ). Alkylmethyl groups such as ₂ −, −C (CH ₃ ) (CH ₂ CH ₃ ) −, −C (CH ₃ ) (CH ₂ CH ₂ CH ₃ ) −, −C (CH ₂ CH ₃ ) ₂ −, etc.; − CH (CH ₃ ) CH _2- , -CH (CH ₃ ) CH (CH ₃ )-, -C (CH ₃ ) ₂ CH _2- , -CH (CH ₂ CH ₃ ) CH _2- , -C (CH ₂₎ CH ₃ ) _2- CH ₂ -etc. Alkylethylene groups; -CH (CH ₃ ) CH ₂ CH _2- , -CH ₂ CH (CH ₃ ) CH ₂ -etc. Alkylmethyl group; -CH (CH ₃ ) Examples thereof include alkylalkylene groups such as alkyltetramethylene groups such as CH ₂ CH ₂ CH ₂ − and −CH ₂ CH (CH ₃ ) CH ₂ CH ₂ −. As the alkyl group in the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferable.

An aliphatic hydrocarbon group containing a ring in the structure The aliphatic hydrocarbon group containing a ring in the structure is an alicyclic hydrocarbon group (a group obtained by removing two hydrogen atoms from an aliphatic hydrocarbon ring). , A group in which an alicyclic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, or an alicyclic hydrocarbon group in the middle of a linear or branched aliphatic hydrocarbon group Examples include groups intervening in. Examples of the linear or branched aliphatic hydrocarbon group include the same groups as described above.
The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably 3 to 12 carbon atoms.
The alicyclic hydrocarbon group may be a polycyclic type or a monocyclic type. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. As the polycyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from polycycloalkane is preferable, and the polycycloalkane preferably has 7 to 12 carbon atoms, specifically, adamantane. , Norbornane, isobornane, tricyclodecane, tetracyclododecane and the like.

-Aromatic hydrocarbon group An aromatic hydrocarbon group is a hydrocarbon group having an aromatic ring.
Aromatic hydrocarbon group as the divalent hydrocarbon group for ^{W b} is preferably 3 to 30 carbon atoms, more preferably 5-30, more preferably 5-20, particularly preferably 6 to 15, 6 10 is most preferable. However, the carbon number does not include the carbon number in the substituent.
Specifically, the aromatic ring contained in the aromatic hydrocarbon group is an aromatic hydrocarbon ring such as benzene, biphenyl, fluorene, naphthalene, anthracene, or phenanthrene; a part of carbon atoms constituting the aromatic hydrocarbon ring is heterogeneous. Aromatic heterocycles substituted with atoms; etc. Examples of the hetero atom in the aromatic heterocycle include an oxygen atom, a sulfur atom, a nitrogen atom and the like.
Specifically, as the aromatic hydrocarbon group, a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring (arylene group, preferably a phenylene group or a naphthylene group); a hydrogen atom from the aromatic hydrocarbon ring. A group in which one of the hydrogen atoms of the removed group (aryl group) is substituted with an alkylene group (for example, a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, 2 -A group obtained by removing one more hydrogen atom from an aryl group in an arylalkyl group such as a naphthylethyl group); and the like. The alkylene group (alkyl chain in the arylalkyl group) preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon atom.

Substituents that the hydrocarbon group of W ^b may have include an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an electron-withdrawing group described later, an oxo group (= O), and a hydroxyl group. Examples thereof include (-OH) and an amino group (-NH ₂ ).

Among them, as W ^b , an aromatic hydrocarbon group is preferable, and as the aromatic ring contained in the aromatic hydrocarbon group, benzene or naphthalene is preferable, and benzene is more preferable.

In the general formula (b1), R ^{b1 to} R ^b8 are independently electron-withdrawing groups or hydrogen atoms. However, at least one of R ^{b1 to} R ^b8 is an electron-withdrawing group. Of R ^{b1 to} R ^b8 in the formula (b1), R ^b1 and R ^b5 or R ^b6 are preferably at least an electron-withdrawing group.
Examples of the electron-withdrawing group include a halogen atom, an alkyl halide group, an alkoxy halide group, an aryloxy halide group, an alkylamino group halide, an alkylthio halide group, an alkyloxycarbonyl group, an aryloxycarbonyl group and a cyano group. , Nitro group, dialkylphosphono group, diarylphosphono group, alkylsulfonyl group, arylsulfonyl group, sulfonyloxy group, acylthio group, sulfamoyl group, thiocianate group, thiocarbonyl group.
Among the above, a halogen atom or an alkyl halide group is preferable.
The alkyl halide group is preferably an alkyl halide group having 1 to 10 carbon prime numbers. An alkyl halide group having 1 to 10 carbon atoms is a group in which a part or all of hydrogen atoms of an alkyl group having 1 to 10 carbon atoms are substituted with a halogen atom. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like, and a fluorine atom is particularly preferable.
Among them, as R ^{b1 to} R ^b8 , a trifluoromethyl group, a fluorine atom or a hydrogen atom is preferable.

In the general formula (b1), R ^{s1 to} R ^s4 are independent substituents. Examples of the substituent of R ^{s1 to} R ^s4 include an alkyl group, a halogen atom, an alkyl halide group, a carbonyl group, a cyano group, an amino group, an aryl group, an arylthio group, and the following formulas (ca-r-1) to ( Examples thereof include groups represented by ca-r-7).
Examples of the aryl group in the arylthio group as a substituent include a phenylthio group or a biphenylthio group.

［式中、Ｒ’^２０１はそれぞれ独立に、水素原子、置換基を有していてもよい環式基、鎖状のアルキル基、または鎖状のアルケニル基である。］

[In the formula, ^R'201 is independently a hydrogen atom, a cyclic group which may have a substituent, a chain alkyl group, or a chain alkenyl group. ]

R ^'201 which may have a substituent cyclic group, substituent having optionally also good chain alkyl group or have a substituent which may chain alkenyl groups, is the In addition to the same as R ¹⁰¹ in the formula (b-1), a cyclic group which may have a substituent or a chain alkyl group which may have a substituent will be described later. The same as the acid dissociable group represented by (a1-r-2) can also be mentioned.

In the general formula (b1), n _{b1 to} n _b4 are independently integers of 0 to 3, preferably 0 or 1, and more preferably 0.

In the general formula (b1), Z ⁿ⁻ is an n-valent anion, and n is an integer of 1 or more. n is preferably 1 or 2, more preferably 1.
Examples of the Z ⁿ⁻ anion include an anion represented by the following general formula (b1-a1), an anion represented by the general formula (b1-a2), or an anion represented by the general formula (b1-a3). Anions can be used.

［式中、Ｒ^１０１、Ｒ^１０４〜Ｒ^１０８はそれぞれ独立に置換基を有していてもよい環式基、置換基を有していてもよい鎖状のアルキル基、または置換基を有していてもよい鎖状のアルケニル基である。Ｒ^１０４、Ｒ^１０５は、相互に結合して環を形成していてもよい。Ｒ^１０６〜Ｒ^１０８のいずれか２つは、相互に結合して環を形成していてもよい。Ｒ^１０２はフッ素原子または炭素数１〜５のフッ素化アルキル基である。Ｙ^１０１は単結合または酸素原子を含む２価の連結基である。Ｖ^１０１〜Ｖ^１０３はそれぞれ独立に単結合、アルキレン基、またはフッ素化アルキレン基である。Ｌ^１０１〜Ｌ^１０２はそれぞれ独立に単結合または酸素原子である。Ｌ^１０３〜Ｌ^１０５はそれぞれ独立に単結合、−ＣＯ−又は−ＳＯ_２−である。］

[In the formula, R ¹⁰¹ and R ^{104 to} R ¹⁰⁸ each have a cyclic group which may independently have a substituent, a chain alkyl group which may have a substituent, or a substituent. It is a chain alkenyl group that may be present. R ¹⁰⁴ and R ¹⁰⁵ may be coupled to each other to form a ring. Any two of R ^{106 to} R ¹⁰⁸ may be coupled to each other to form a ring. R ¹⁰² is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. Y ¹⁰¹ is a single bond or a divalent linking group containing an oxygen atom. V ^{101 to} V ¹⁰³ are independently single bonds, alkylene groups, or fluorinated alkylene groups, respectively. L ^{101 to} L ¹⁰² are independently single bonds or oxygen atoms, respectively. L ¹⁰³ ~L ¹⁰⁵ are each independently a single bond, -CO- or -SO ₂ - is. ]

In formula (b1-a1), R ¹⁰¹ may have a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a substituent. It is a chain alkenyl group.

A cyclic group which may have a substituent in R ¹⁰¹ The cyclic group is preferably a cyclic hydrocarbon group, and the cyclic hydrocarbon group is an aromatic hydrocarbon group. It may be an aliphatic hydrocarbon group.
The aromatic hydrocarbon group in R ¹⁰¹ is the aromatic hydrocarbon ring mentioned in the divalent aromatic hydrocarbon group in Va ¹ in the formula (a1-1) described later, or an aromatic containing two or more aromatic rings. Examples thereof include an aryl group obtained by removing one hydrogen atom from the compound, and a phenyl group and a naphthyl group are preferable.
The cyclic aliphatic hydrocarbon group in R ¹⁰¹ is obtained by removing one hydrogen atom from the monocycloalkane or polycycloalkane listed in the divalent aliphatic hydrocarbon group in Va ¹ in the formula (a1-1) described later. Examples thereof include an adamantyl group and a norbornyl group, which are preferable.
Further, the cyclic hydrocarbon group in R ¹⁰¹ may contain a hetero atom such as a heterocycle, and specifically, each of them is represented by the general formulas (a2-r-1) to (a2-r-7) described later. The lactone-containing cyclic group represented, the -SO ₂ -containing cyclic group represented by the above general formulas (a5-r-1) to (a5-r-4), respectively, the following chemical formula (r-hr-1). Examples thereof include heterocyclic groups represented by ~ (r-hr-16).

Examples of the substituent in the cyclic hydrocarbon group of R ¹⁰¹ include an alkyl group, an alkoxy group, a halogen atom, an alkyl halide group, a hydroxyl group, a carbonyl group, a nitro group and the like.
As the alkyl group as the substituent, an alkyl group having 1 to 5 carbon atoms is preferable, and a methyl group, an ethyl group, a propyl group, an n-butyl group and a tert-butyl group are most preferable.
As the alkoxy group as the substituent, an alkoxy group having 1 to 5 carbon atoms is preferable, a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group and a tert-butoxy group are more preferable, and methoxy. Groups and ethoxy groups are most preferred.
Examples of the halogen atom as the substituent include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like, and a fluorine atom is preferable.
As the alkyl halide group as a substituent, a part or all of hydrogen atoms such as an alkyl group having 1 to 5 carbon atoms, for example, a methyl group, an ethyl group, a propyl group, an n-butyl group and a tert-butyl group are described above. Examples include groups substituted with halogen atoms.

Chain-shaped alkyl group which may have a substituent on R ¹⁰¹ The chain-shaped alkyl group of R ¹⁰¹ may be either linear or branched.
The linear alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and most preferably 1 to 10 carbon atoms. Specifically, for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, isotridecyl group, tetradecyl. Examples thereof include a group, a pentadecyl group, a hexadecyl group, an isohexadecyl group, a heptadecyl group, an octadecyl group, a nonadecil group, an icosyl group, a henicosyl group and a docosyl group.
The branched-chain alkyl group preferably has 3 to 20 carbon atoms, more preferably 3 to 15 carbon atoms, and most preferably 3 to 10 carbon atoms. Specifically, for example, 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, Examples thereof include 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group and 4-methylpentyl group.

The chain alkenyl group of alkenyl group R ¹⁰¹ may be chain substituted in · · R ^101, may be either linear or branched, is 2-10 carbon atoms Of the above, 2 to 5 are more preferable, 2 to 4 are even more preferable, and 3 is particularly preferable. Examples of the linear alkenyl group include a vinyl group, a propenyl group (allyl group), a butynyl group and the like. Examples of the branched chain alkenyl group include a 1-methylpropenyl group and a 2-methylpropenyl group.
Among the above, the propenyl group is particularly preferable as the chain alkenyl group.

Examples of the substituent in the chain alkyl group or alkenyl group of R ¹⁰¹ include an alkoxy group, a halogen atom, an alkyl halide group, a hydroxyl group, a carbonyl group, a nitro group, an amino group, and a cyclic group in R ¹⁰¹ . Can be mentioned.

Among them, R ¹⁰¹ is preferably a cyclic group which may have a substituent, and more preferably a cyclic hydrocarbon group which may have a substituent. More specifically, a phenyl group, a naphthyl group, a group obtained by removing one or more hydrogen atoms from a polycycloalkane, are represented by the above general formulas (a2-r-1) to (a2-r-7), respectively. lactone-containing cyclic group, -SO ₂ respectively represented by the general formula (a5-r-1) ~ (a5-r-4) - containing cyclic group and the like.

In formula (b1-a1), Y ¹⁰¹ is a single bond or a divalent linking group containing an oxygen atom.
When Y ¹⁰¹ is a divalent linking group containing an oxygen atom, the Y ¹⁰¹ may contain an atom other than the oxygen atom. Examples of atoms other than oxygen atoms include carbon atoms, hydrogen atoms, sulfur atoms, nitrogen atoms and the like.
Examples of the divalent linking group containing an oxygen atom include an oxygen atom (ether bond: −O−), an ester bond (−C (= O) −O−), and an oxycarbonyl group (−OC (= O−). )-), Amid bond (-C (= O) -NH-), carbonyl group (-C (= O)-), carbonate bond (-O-C (= O) -O-) and other non-carbohydrates Oxygen atom-containing linking group of the system; Examples thereof include a combination of the oxygen atom-containing linking group of the non-hydrogen system and an alkylene group. A sulfonyl group (-SO _2- ) may be further linked to the combination. Examples of the combination include linking groups represented by the following formulas (y-al-1) to (y-al-7), respectively.

［式中、Ｖ’^１０１は単結合または炭素数１〜５のアルキレン基であり、Ｖ’^１０２は炭素数１〜３０の２価の飽和炭化水素基である。］

Wherein, V ^'101 represents a single bond or an alkylene group having 1 to 5 carbon atoms, V' ¹⁰² is a divalent saturated hydrocarbon group having 1 to 30 carbon atoms. ]

Divalent saturated hydrocarbon group in V ^'102 is preferably an alkylene group having 1 to 30 carbon atoms.

The alkylene group for V ^'101 and V' ^102, may be linear well branched alkylene group with an alkylene group, a linear alkylene group is preferable.
As the alkylene group for V ^'101 and V' ^102, specifically, a methylene group _{[-CH 2 -]; - CH} (CH 3) -, - CH (CH 2 CH 3) -, - C (CH 3) Alkylmethyl groups such as _2- , -C (CH ₃ ) (CH ₂ CH ₃ )-, -C (CH ₃ ) (CH ₂ CH ₂ CH ₃ )-, -C (CH ₂ CH ₃ ) _2-, etc.; Group [-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 ) Alkylethylene groups such as CH _2- ; trimethylene group (n-propylene group) [-CH ₂ CH ₂ CH _2- ]; -CH (CH ₃ ) CH ₂ CH _2- , -CH ₂ CH (CH ₃ ) Alkylmethylethylene groups such as CH _2- ; tetramethylene groups [-CH ₂ CH ₂ CH ₂ CH _2- ]; -CH (CH ₃ ) CH ₂ CH ₂ CH _2- , -CH ₂ CH (CH ₃ ) CH ₂ Alkyltetramethylene groups such as CH _2- ; pentamethylene groups [-CH ₂ CH ₂ CH ₂ CH ₂ CH _2- ] and the like can be mentioned.
A part of the methylene groups in the alkylene group for V ^'101 or V' ¹⁰² may be substituted by a divalent aliphatic cyclic group having 5 to 10 carbon atoms. The aliphatic cyclic group, the formula (a1-r-1) 2 monovalent group further one except a hydrogen atom from an aliphatic hydrocarbon group of Ra ^'3 annular in preferably, cyclohexylene group , 1,5-adamantylene group or 2,6-adamantylene group is more preferable.

As Y ¹⁰¹ , a divalent linking group containing an ester bond or an ether bond is preferable, and linking groups represented by the above formulas (y-al-1) to (y-al-5) are preferable.

In formula (b1-a1), V ¹⁰¹ is a single bond, an alkylene group, or a fluorinated alkylene group. The alkylene group and the fluorinated alkylene group in V ¹⁰¹ preferably have 1 to 4 carbon atoms. ^Examples of the fluorinated alkylene group in V ¹⁰¹ include a group in which a part or all of hydrogen atoms of the alkylene group in V ¹⁰¹ are substituted with a fluorine atom. Among them, V ¹⁰¹ is preferably a single bond or a fluorinated alkylene group having 1 to 4 carbon atoms.

In formula (b1-a1), R ¹⁰² is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. R ¹⁰² is preferably a fluorine atom or a perfluoroalkyl group having 1 to 5 carbon atoms, and more preferably a fluorine atom.

Specific examples of the anion portion of the component (b1-a1) include fluorinated alkyl sulfonate anions such as trifluoromethanesulfonate anion and perfluorobutane sulfonate anion when Y ¹⁰¹ is a single bond; Y ¹⁰¹ is When it is a divalent linking group containing an oxygen atom, an anion represented by any of the following formulas (an-1) to (an-3) can be mentioned.

［式中、Ｒ”^１０１は、置換基を有していてもよい脂肪族環式基、前記式（ｒ−ｈｒ−１）〜（ｒ−ｈｒ−６）でそれぞれ表される基、又は置換基を有していてもよい鎖状のアルキル基であり；Ｒ”^１０２は、置換基を有していてもよい脂肪族環式基、前記一般式（ａ２−ｒ−１）〜（ａ２−ｒ−７）でそれぞれ表されるラクトン含有環式基、又は前記一般式（ａ５−ｒ−１）〜（ａ５−ｒ−４）でそれぞれ表される−ＳＯ_２−含有環式基であり；Ｒ”^１０３は、置換基を有していてもよい芳香族環式基、置換基を有していてもよい脂肪族環式基、又は置換基を有していてもよい鎖状のアルケニル基であり；Ｖ”^１０１は、フッ素化アルキレン基であり；Ｌ”^１０１は、−Ｃ（＝Ｏ）−又は−ＳＯ_２−であり；ｖ”はそれぞれ独立に０〜３の整数であり、ｑ”はそれぞれ独立に１〜２０の整数であり、ｎ”は０または１である。］

[In the formula, R " ¹⁰¹ is an aliphatic cyclic group which may have a substituent, a group represented by the above formulas (r-hr-1) to (r-hr-6), or a substitution. It is a chain alkyl group which may have a group; R " ¹⁰² is an aliphatic cyclic group which may have a substituent, the general formulas (a2-r-1) to (a2-). lactone-containing cyclic group represented respectively by r-7), or the formula (a5-r-1) ~ (a5-r-4) with -SO ₂ respectively represented - be-containing cyclic group; R " ¹⁰³ is an aromatic cyclic group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a chain alkenyl group which may have a substituent. V " ¹⁰¹ is a fluorinated alkylene group; L" ¹⁰¹ is -C (= O)-or -SO _2- ; v "is an independently integer of 0 to 3, q. "Is an integer of 1 to 20 independently, and n" is 0 or 1. ]

The aliphatic cyclic group which may have the substituents of R " ¹⁰¹ , R" ¹⁰² and R " ¹⁰³ is preferably the group exemplified as the cyclic aliphatic hydrocarbon group in R ¹⁰¹ . Examples of the substituent include the same substituents which may replace the cyclic aliphatic hydrocarbon group in R ¹⁰¹ .

The aromatic cyclic group which may have a substituent in R " ¹⁰³ is preferably a group exemplified as an aromatic hydrocarbon group in the cyclic hydrocarbon group in R ^101. The substituent is preferably a group. , R ¹⁰¹ , the same as the substituent which may replace the aromatic hydrocarbon group.

The chain-like alkyl group which may have a substituent at R " ¹⁰¹ is preferably a group exemplified as the chain-like alkyl group at R ^{101. It} has a substituent at R " ¹⁰³ . The chain-like alkenyl group may be preferably the group exemplified as the chain-like alkenyl group in R ¹⁰¹ . V ^"101 is preferably a fluorinated alkylene group having 1 to 3 carbon atoms, particularly _{preferably, -CF 2 -, - CF 2} CF 2 -, - CHFCF 2 -, - CF (CF 3) CF 2 - , -CH (CF ₃ ) CF _2- .

In the formula (b1-a2), R ¹⁰⁴ and R ¹⁰⁵ are independently cyclic groups which may have a substituent, chain alkyl groups which may have a substituent, or substituents. It is a chain alkenyl group which may have, and the same group as R ¹⁰¹ in the formula (b1-a1) can be mentioned. However, R ¹⁰⁴ and R ¹⁰⁵ may be coupled to each other to form a ring.
R ¹⁰⁴ and R ¹⁰⁵ are preferably chain-like alkyl groups which may have a substituent, and are linear or branched-chain alkyl groups, or linear or branched-chain fluorinated alkyl groups. Is more preferable.
The chain alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 7 carbon atoms, and further preferably 1 to 3 carbon atoms. The carbon number of the chain alkyl group of R ¹⁰⁴ and R ¹⁰⁵ is preferably as small as possible because the solubility in the resist solvent is also good within the range of the carbon number. Further, in the chain alkyl groups of R ¹⁰⁴ and R ^105, the larger the number of hydrogen atoms substituted with fluorine atoms, the stronger the acid strength, and the stronger the acid strength, and the higher the strength of the acid with respect to high-energy light or electron beam of 200 nm or less. It is preferable because it improves transparency. The ratio of fluorine atoms in the chain alkyl group, that is, the fluorination rate is preferably 70 to 100%, more preferably 90 to 100%, and most preferably all hydrogen atoms are substituted with fluorine atoms. It is a perfluoroalkyl group.
In the formula (b1-a2), V ¹⁰² and V ¹⁰³ are each independently a single bond, an alkylene group, or a fluorinated alkylene group, and each of them is the same as V ¹⁰¹ in the formula (b1-a1). Can be mentioned.
In formula (b1-a2), L ^{101 to} L ¹⁰² are independently single bonds or oxygen atoms, respectively.

In the formula (b1-a3), R ^{106 to} R ¹⁰⁸ are each independently a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a substituent. It is a chain alkenyl group which may have, and the same group as R ¹⁰¹ in the formula (b1-a1) can be mentioned.
L ^{103 to} L ¹⁰⁵ are each independently single-bonded, -CO- or -SO _2- .

As the component (B1), a compound represented by the following general formula (b1-1) is preferable.

［式中、Ｒ^ｓｗは、置換基である。Ｒ^ｂ１１及びＲ^ｂ５１は、それぞれ独立に、電子吸引性基である。Ｒ^ｂ２１〜Ｒ^ｂ４１、Ｒ^ｂ６１〜Ｒ^ｂ８１は、それぞれ独立に、電子吸引性基又は水素原子である。Ｒ^ｓ１〜Ｒ^ｓ４は、それぞれ独立に、置換基である。ｎ_ｂ１〜ｎ_ｂ４は、それぞれ独立に、０〜３の整数である。Ｚ^ｎ−は、ｎ価のアニオンであり、ｎは１以上の整数である。］

[In the formula, R ^sw is a substituent. R ^b11 and R ^b51 are each independently an electron-withdrawing group. R ^{b21 to} R ^b41 and R ^{b61 to} R ^b81 are independently electron-withdrawing groups or hydrogen atoms. R ^{s1 to} R ^s4 are independent substituents. n _{b1 to} n _b4 are independently integers of 0 to 3. Z ⁿ⁻ is an n-valent anion, and n is an integer of 1 or more. ]

In the general formula (b1-1), R ^sw is a substituent. The substituent of R ^{sw is the same as} the substituent of R ^{s1 to} R ^{s4 in} the general formula (b1).
In the general formula (b1-1), n _bw is an integer of 0 to 4, preferably 0 or 1, and more preferably 0.
In the general formula (b1-1), R ^b11 and R ^b51 are independently electron-withdrawing groups. The electron-withdrawing groups of R ^b11 and R ^b51 are the same as the electron-withdrawing groups of R ^{b1 to} R ^{b8 in} the general formula (b1). Among them, the electron-withdrawing group of R ^b11 and R ^b51 is preferably a trifluoromethyl group or a fluorine atom.
In the general formula ( ^b1-1 ), R ^{b21 to} R ^b41 and R ^{b61 to} R ^b81 are independently electron-withdrawing groups or hydrogen atoms, respectively. The electron-withdrawing groups of R ^{b21 to} R ^b41 and R ^{b61 to} R ^b81 are the same as the electron-withdrawing groups of R ^{b1 to} R ^{b8 in} the general formula (b1). Among them, R ^{b21 to} R ^b41 and R ^{b61 to} R ^b81 are preferably a trifluoromethyl group, a fluorine atom or a hydrogen atom.
In the general formula (b1-1), R ^{s1 to} R ^s4 , n _{b1 to} n _b4 , Z ⁿ⁻ and n are R ^{s1 to} R ^s4 , n _{b1 to} n _b4 , Z in the general formula (b1). Similar to ^n- and n.

Specific examples of the component (B1) are shown below.

<(B2) component>
The resist composition of the present invention may contain an acid generator component (hereinafter, referred to as "(B2) component") other than the (B1) component as the (B) component.
The component (B2) is not particularly limited, and those previously proposed as an acid generator for a chemically amplified resist can be used.
Examples of such an acid generator include onium salt-based acid generators such as iodonium salt and sulfonium salt, oxime sulfonate-based acid generators, bisalkyl or bisarylsulfonyldiazomethanes, and diazomethanes such as poly (bissulfonyl) diazomethanes. Various kinds such as an acid generator, a nitrobenzyl sulfonate-based acid generator, an imino sulfonate-based acid generator, and a disulfonate-based acid generator can be mentioned. Of these, it is preferable to use an onium salt-based acid generator.

Examples of the onium salt-based acid generator include a compound represented by the following general formula (b-1) (hereinafter, also referred to as “component (b-1)”) and a general formula (b-2). A compound (hereinafter, also referred to as “(b-2) component”) or a compound represented by the general formula (b-3) (hereinafter, also referred to as “(b-3) component”) can be used.

［式中、Ｒ^１０１、Ｒ^１０４〜Ｒ^１０８はそれぞれ独立に置換基を有していてもよい環式基、置換基を有していてもよい鎖状のアルキル基、または置換基を有していてもよい鎖状のアルケニル基である。Ｒ^１０４、Ｒ^１０５は、相互に結合して環を形成していてもよい。Ｒ^１０６〜Ｒ^１０７のいずれか２つは、相互に結合して環を形成していてもよい。Ｒ^１０２はフッ素原子または炭素数１〜５のフッ素化アルキル基である。Ｙ^１０１は単結合または酸素原子を含む２価の連結基である。Ｖ^１０１〜Ｖ^１０３はそれぞれ独立に単結合、アルキレン基、またはフッ素化アルキレン基である。Ｌ^１０１〜Ｌ^１０２はそれぞれ独立に単結合または酸素原子である。Ｌ^１０３〜Ｌ^１０５はそれぞれ独立に単結合、−ＣＯ−又は−ＳＯ_２−である。Ｍ’^ｍ＋はｍ価の有機カチオンである。］

[In the formula, R ¹⁰¹ and R ^{104 to} R ¹⁰⁸ each have a cyclic group which may independently have a substituent, a chain alkyl group which may have a substituent, or a substituent. It is a chain alkenyl group that may be present. R ¹⁰⁴ and R ¹⁰⁵ may be coupled to each other to form a ring. Any two of R ^{106 to} R ¹⁰⁷ may be coupled to each other to form a ring. R ¹⁰² is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. Y ¹⁰¹ is a single bond or a divalent linking group containing an oxygen atom. V ^{101 to} V ¹⁰³ are independently single bonds, alkylene groups, or fluorinated alkylene groups, respectively. L ^{101 to} L ¹⁰² are independently single bonds or oxygen atoms, respectively. L ¹⁰³ ~L ¹⁰⁵ are each independently a single bond, -CO- or -SO ₂ - is. ^{M'm +} is an m-valent organic cation. ]

In the formulas (b-1) to (b-3), R ¹⁰¹ , R ^{104 to} R ¹⁰⁸ , R ¹⁰² , Y ¹⁰¹ , V ^{101 to} V ¹⁰³ , L ^{101 to} L ¹⁰² , and L ^{103 to} L ¹⁰⁵ , respectively. Similar to R ¹⁰¹ , R ^{104 to} R ¹⁰⁸ , R ¹⁰² , Y ¹⁰¹ , V ^{101 to} V ¹⁰³ , L ^{101 to} L ¹⁰² , and L ^{103 to} L ^{105 in the} formulas (b1-a1) to (b1-a3). is there.
In formulas (b-1), (b-2) and (b-3), ^{M'm +} is an m-valent organic cation, preferably a sulfonium cation or an iodonium cation, and the following general formula. The cations represented by (ca-1) to (ca-4) are particularly preferable.

［式中、Ｒ^２０１〜Ｒ^２０７、およびＲ^２１１〜Ｒ^２１２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、アルキル基またはアルケニル基を表し、Ｒ^２０１〜Ｒ^２０３、Ｒ^２０６〜Ｒ^２０７、Ｒ^２１１〜Ｒ^２１２は、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い。Ｒ^２０８〜Ｒ^２０９はそれぞれ独立に水素原子または炭素数１〜５のアルキル基を表し、Ｒ^２１０は置換基を有していてもよいアリール基、アルキル基、アルケニル基、又は−ＳＯ_２−含有環式基であり、Ｌ^２０１は−Ｃ（＝Ｏ）−または−Ｃ（＝Ｏ）−Ｏ−を表し、Ｙ^２０１は、それぞれ独立に、アリーレン基、アルキレン基またはアルケニレン基を表し、ｘは１または２であり、Ｗ^２０１は（ｘ＋１）価の連結基を表す。］

[In the formula, R ^{201 to} R ²⁰⁷ and R ^{211 to} R ²¹² represent aryl groups, alkyl groups or alkenyl groups, which may have independent substituents, respectively, and R ^{201 to} R ²⁰³ and R ²⁰⁶ to R ²⁰⁶ . R ²⁰⁷ and R ^{211 to} R ²¹² may be bonded to each other to form a ring together with the sulfur atom in the formula. R ^{208 to} R ²⁰⁹ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and R ²¹⁰ contains an aryl group, an alkyl group, an alkenyl group, or -SO _2- which may have a substituent. It is a cyclic group, L ²⁰¹ represents −C (= O) − or −C (= O) −O−, Y ²⁰¹ independently represents an arylene group, an alkylene group or an alkenylene group, and x is 1 or 2, where W ²⁰¹ represents a (x + 1) valence linking group. ]

Examples of the aryl group in R ^{201 to} R ²⁰⁷ and R ^{211 to} R ²¹² include an unsubstituted aryl group having 6 to 20 carbon atoms, and a phenyl group and a naphthyl group are preferable.
The alkyl group in R ^{201 to} R ²⁰⁷ and R ^{211 to} R ²¹² is preferably a chain or cyclic alkyl group having 1 to 30 carbon atoms.
The alkenyl group in R ^{201 to} R ²⁰⁷ and R ^{211 to} R ²¹² preferably has 2 to 10 carbon atoms.
Substituents that R ^{201 to} R ²⁰⁷ and R ^{210 to} R ²¹² may have include, for example, an alkyl group, a halogen atom, an alkyl halide group, a carbonyl group, a cyano group, an amino group, an aryl group, and an arylthio. Examples thereof include groups represented by the above formulas (ca-r-1) to (ca-r-7), respectively.
The aryl group in the arylthio group as a substituent is the same as that mentioned in R ¹⁰¹ , and specific examples thereof include a phenylthio group and a biphenylthio group.

When R ^{201 to} R ²⁰³ , R ^{206 to} R ²⁰⁷ , and R ^{211 to} R ²¹² are bonded to each other to form a ring together with the sulfur atom in the formula, heteroatoms such as sulfur atom, oxygen atom, and nitrogen atom, and heteroatoms such as sulfur atom and nitrogen atom carbonyl _{group, -SO -, - SO 2 -} , - SO 3 -, - COO -, - CONH- , or -N _(R N) - (. the _{R N} is an alkyl group having 1 to 5 carbon atoms), etc. It may be bonded via a functional group of. As the ring to be formed, one ring containing a sulfur atom in its ring skeleton, including the sulfur atom, is preferably a 3 to 10-membered ring, and particularly preferably a 5- to 7-membered ring. preferable. Specific examples of the ring to be formed include, for example, a thiophene ring, a thiazole ring, a benzothiophene ring, a thianthrene ring, a benzothiophene ring, a dibenzothiophene ring, a 9H-thioxanthene ring, a thioxanthone ring, a thianthrene ring, a phenoxatiin ring, and a tetrahydro. Examples thereof include a thiophenium ring and a tetrahydrothiopyranium ring.

R ^{208 to} R ²⁰⁹ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and when they are alkyl groups, they are bonded to each other to form a ring. May be formed.

R ²¹⁰ may have an aryl group which may have a substituent, an alkyl group which may have a substituent, an alkenyl group which may have a substituent, or a substituent. -SO ₂ -containing cyclic group.
^Examples of the aryl group in R ²¹⁰ include an unsubstituted aryl group having 6 to 20 carbon atoms, and a phenyl group and a naphthyl group are preferable.
The alkyl group in R ²¹⁰ is preferably a chain or cyclic alkyl group having 1 to 30 carbon atoms.
The alkenyl group in R ²¹⁰ preferably has 2 to 10 carbon atoms.
Examples of the -SO ₂ -containing cyclic group which may have a substituent in R ²¹⁰ include the same as the above-mentioned "-SO ₂ -containing cyclic group", and the above general formula (a5-). The group represented by r-1) is preferable.

Y ²⁰¹ independently represents an arylene group, an alkylene group or an alkenylene group.
Examples of the arylene group in Y ²⁰¹ include a group obtained by removing one hydrogen atom from the aryl group exemplified as the aromatic hydrocarbon group in R ¹⁰¹ in the above formula (b-1).
Examples of the alkylene group and the alkenylene group in Y ²⁰¹ include the same as the aliphatic hydrocarbon group as the divalent hydrocarbon group in Va ¹ in the above general formula (a1-1).

In the formula (ca-4), x is 1 or 2.
W ²⁰¹ is a (x + 1) valence, i.e., a divalent or trivalent linking group.
As the divalent linking group in W ^{201, a} divalent hydrocarbon group which may have a substituent is preferable, and a hydrocarbon group similar to Ya ²¹ in the general formula (a2-1) can be exemplified. The divalent linking group in W ²⁰¹ may be linear, branched or cyclic, and is preferably cyclic. Of these, a group in which two carbonyl groups are combined at both ends of the arylene group is preferable. Examples of the arylene group include a phenylene group and a naphthylene group, and a phenylene group is particularly preferable.
^Examples of the trivalent linking group in W ²⁰¹ include a group obtained by removing one hydrogen atom from the divalent linking group in W ²⁰¹ , and a group in which the divalent linking group is further bonded to the divalent linking group. Can be mentioned. As the trivalent linking group in W ²⁰¹ , a group in which two carbonyl groups are bonded to an arylene group is preferable.

Specific examples of suitable cations represented by the formula (ca-1) include cations represented by the following formulas (ca-1-1) to (ca-1-63).

［式中、ｇ１、ｇ２、ｇ３は繰返し数を示し、ｇ１は１〜５の整数であり、ｇ２は０〜２０の整数であり、ｇ３は０〜２０の整数である。］

[In the formula, g1, g2, g3 indicate the number of repetitions, g1 is an integer of 1 to 5, g2 is an integer of 0 to 20, and g3 is an integer of 0 to 20. ]

［式中、Ｒ”^２０１は水素原子又は置換基であって、置換基としては前記Ｒ^２０１〜Ｒ^２０７、およびＲ^２１０〜Ｒ^２１２が有していてもよい置換基として挙げたものと同様である。］

[In the formula, R " ²⁰¹ is a hydrogen atom or a substituent, and the substituents are the same as those listed as the substituents that R ^{201 to} R ²⁰⁷ and R ^{210 to} R ²¹² may have. is there.]

Specific examples of suitable cations represented by the above formula (ca-3) include cations represented by the following formulas (ca-3-1) to (ca-3-6).

Specific examples of suitable cations represented by the above formula (ca-4) include cations represented by the following formulas (ca-4-1) to (ca-4-2).

As the component (B2), the above-mentioned acid generator may be used alone or in combination of two or more.
When the resist composition contains the component (B2) in the present embodiment, the content of the component (B2) is preferably 0.5 to 60 parts by mass, preferably 1 to 50 parts by mass with respect to 100 parts by mass of the component (A). Parts are more preferable, and 1 to 40 parts by mass are further preferable.
By setting the content of the component (B2) within the above range, pattern formation is sufficiently performed. Further, when each component of the resist composition is dissolved in an organic solvent, a uniform solution is obtained and the storage stability is improved, which is preferable.

The resist composition of the present invention preferably further contains a base material component (A) (hereinafter, referred to as "component (A)") whose solubility in a developing solution is changed by the action of an acid.
In the present invention, the component (A) may be composed of a single polymer compound or may be a mixture of a plurality of polymer compounds.

When the resist composition of the present invention contains the component (A), the content of the component (B1) is preferably 5 to 45 parts by mass with respect to 100 parts by mass of the base material component (A). It is more preferably ~ 40 parts by mass, and even more preferably 15-40 parts by mass.

When a resist film is formed using such a resist composition and selective exposure is performed on the resist film, an acid is generated in the exposed portion, and the action of the acid makes the component (A) soluble in a developing solution. On the other hand, since the solubility of the component (A) in the developing solution does not change in the unexposed portion, a difference in solubility in the developing solution occurs between the exposed portion and the unexposed portion. Therefore, when the resist film is developed, if the resist composition is a positive type, the exposed portion is dissolved and removed to form a positive type resist pattern, and if the resist composition is a negative type, the unexposed portion is dissolved. It is removed to form a negative resist pattern.
In the present specification, a resist composition in which an exposed portion is dissolved and removed to form a positive resist pattern is referred to as a positive resist composition, and a resist composition for forming a negative resist pattern in which an unexposed portion is dissolved and removed. Is called a negative resist composition.
In the present invention, the resist composition may be a positive resist composition or a negative resist composition.
Further, in the present invention, the resist composition may be used for an alkaline developing process in which an alkaline developing solution is used for the developing process at the time of forming a resist pattern, and a developing solution (organic developing solution) containing an organic solvent in the developing process. It may be for a solvent developing process using, but it is preferably for a solvent developing process.

In the present invention, the resist composition has an acid-generating ability to generate an acid by exposure, and the component (A) may generate an acid by exposure, and is added separately from the component (A). The agent component may generate an acid upon exposure.
Specifically, in the present invention, the resist composition is:
(1) It may contain the component (B) that generates an acid upon exposure;
(2) The component (A) may be a component that generates an acid upon exposure;
(3) The component (A) may be a component that generates an acid upon exposure and may further contain a component (B).
That is, in the cases of (2) and (3) above, the component (A) is "a base material component that generates an acid by exposure and whose solubility in a developing solution changes by the action of the acid". When the component (A) is a base material component that generates an acid by exposure and whose solubility in a developing solution changes due to the action of the acid, the component (A1) described later generates an acid by exposure and the solubility in the developer changes. It is preferably a polymer compound whose solubility in a developing solution changes due to the action of an acid. As such a polymer compound, a resin having a structural unit that generates an acid upon exposure can be used. As the structural unit that generates an acid by exposure, a known one can be used.
In the present invention, the resist composition is particularly preferably in the case of (1) above.

<Ingredient (A)>
In the present invention, 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 in addition, a nano-level photosensitive resin pattern is easily formed.
Organic compounds used as base material components are roughly classified into non-polymers and polymers.
As the non-polymer, those having a molecular weight of 500 or more and less than 4000 are usually used. Hereinafter, the term "low molecular weight compound" refers to a non-polymer having a molecular weight of 500 or more and less than 4000.
As the polymer, a polymer having a molecular weight of 1000 or more is usually used. Hereinafter, the term "resin" refers to a polymer having a molecular weight of 1000 or more.
As the molecular weight of the polymer, the polystyrene-equivalent weight average molecular weight by GPC (gel permeation chromatography) shall be used.
As the component (A), a resin may be used, a low molecular weight compound may be used, or these may be used in combination.
The component (A) may be one in which the solubility in a developing solution is increased by the action of an acid, or the solubility in a developing solution may be decreased by the action of an acid.
Further, in the present invention, the component (A) may generate an acid by exposure.

(Constituent unit (a0))
In the present invention, the component (A) may contain a structural unit (a0) represented by the following general formula (a0-1).

［式中、Ｒは水素原子、炭素数１〜５のアルキル基または炭素数１〜５のハロゲン化アルキル基である。
Ｙａは炭素原子、
ＸａはＹａとともに２価の環状の炭化水素基を形成する基である。この環状の炭化水素基の有する水素原子の一部又は全部は置換されていてもよい。
Ｒａ^０１〜Ｒａ^０３は、それぞれ独立して、水素原子、炭素数１〜１０の１価の鎖状飽和炭化水素基又は炭素数３〜２０の１価の脂肪族環状飽和炭化水素基である。この鎖状飽和炭化水素基及び脂肪族飽和環状炭化水素基の有する水素原子の一部又は全部は置換されていてもよい。但し、Ｒａ^０１〜Ｒａ^０３の２以上が互いに結合して環状構造を形成していてもよい。］

[In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or an alkyl halide group having 1 to 5 carbon atoms.
Ya is a carbon atom,
Xa is a group that forms a divalent cyclic hydrocarbon group together with Ya. A part or all of the hydrogen atom contained in this cyclic hydrocarbon group may be substituted.
Ra ^{01 to} Ra ⁰³ are independently hydrogen atoms, monovalent chain saturated hydrocarbon groups having 1 to 10 carbon atoms, or monovalent aliphatic cyclic saturated hydrocarbon groups having 3 to 20 carbon atoms. A part or all of the hydrogen atoms contained in the chain saturated hydrocarbon group and the aliphatic saturated cyclic hydrocarbon group may be substituted. However, two or more of Ra ^{01 to} Ra ⁰³ may be bonded to each other to form an annular structure. ]

[R]
In the general formula (a0-1), the alkyl group having 1 to 5 carbon atoms in R is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specifically, a methyl group or ethyl. Examples thereof include groups, propyl groups, isopropyl groups, n-butyl groups, isobutyl groups, tert-butyl groups, pentyl groups, isopentyl groups, neopentyl groups and the like. The alkyl halide group having 1 to 5 carbon atoms is a group in which a part or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like, and a fluorine atom is particularly preferable.
As R, a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a fluorinated alkyl group having 1 to 5 carbon atoms is preferable, and a hydrogen atom or a methyl group is most preferable from the viewpoint of industrial availability.

[Xa]
Xa is a group that forms a divalent cyclic hydrocarbon group together with the carbon atom of Ya.
That is, the carbon atom of Ya to which Xa is bonded has two bonds that are bonded to the oxygen atom of the ester group and the double bond carbon, respectively, in addition to the divalent bond that is bonded to Xa.
The divalent cyclic hydrocarbon group of Ya may be an aliphatic group or an aromatic group.
In the general formula (a0-1), the number of carbon atoms of the cyclic hydrocarbon group formed by Xa together with Ya is not particularly limited, but is preferably 5 to 25, more preferably 5 to 20, and even more preferably 5. ~ 15.
When the divalent cyclic hydrocarbon group of Ya is an aliphatic cyclic hydrocarbon group, it may be of a monocyclic type or a polycyclic type. Specific structures of the aliphatic cyclic hydrocarbon group include, for example, a cyclopropanediyl group, a cyclobutanediyl group, a cyclopentanediyl group, a cyclohexanediyl group, a cycloheptandiyl group, a cyclooctanediyl group, a cyclodecandyl group, and a cyclo. Monocyclic aliphatic saturated hydrocarbon group such as dodecandyl group; cyclobutendyl group, cyclopentendyl group, cyclohexendyl group, cyclodecendyl group, cyclododecendyl, cyclopentadiendyl group, cyclohexadiendyl group, cyclodeca Monocyclic aliphatic unsaturated hydrocarbon group such as diendiyl group; bicyclo [2.2.1] heptenediyl group, bicyclo [2.2.2] octanediyl group, tricyclo [5.2.1.02,6] ] Decandyl group, tricyclo [3.3.1.13,7] decandyl group, tetracyclo [6.2.1.13,6.02,7] dodecandyl group, adamantandiyl group and other polycyclic aliphatic saturated carbides Hydrogen group; bicyclo [2.2.1] heptenedyl group, bicyclo [2.2.2] octendyl group, tricyclo [5.2.1.02,6] decendyl group, tricyclo [3.3.1.1. Examples thereof include a polycyclic aliphatic unsaturated hydrocarbon group such as a 3,7] decendyl group and a tetracyclo [6.2.1.13, 6.02,7] dodecenyl group.

Among these, monocyclic aliphatic saturated hydrocarbon groups and monocyclic aliphatic unsaturated hydrocarbon groups are preferable, and monocyclic aliphatic saturated hydrocarbon groups are preferable from the viewpoint of improving the pattern forming property and LWR performance of the resist composition. A hydrocarbon group is more preferable, and among them, a cyclopentanediyl group, a cyclohexanediyl group, a cycloheptandiyl group, and a cyclooctanediyl group are further preferable.
Among these, the cyclopentanediyl group is particularly preferable from the viewpoint of the ease of dissociation of the acid dissociative group.
The reason why the pattern formability and LWR performance of the resist composition are particularly improved by adopting these monocyclic aliphatic saturated hydrocarbon groups having 5 to 8 carbon atoms is the diffusion length of the acid in the resist film. Can be shortened. As described above, the reason why the diffusion length of the acid is shortened is not always clear, but since the low molecular weight substance generated from the acid dissociable group is easily volatilized by the dissociation reaction, it is difficult to remain in the resist film, and as a result, the resist film. It is conceivable that the acid diffusion coefficient becomes smaller due to the lower plasticity of the acid.

Further, since the ease of dissociation of the acid dissociable group is improved and the etching resistance of the formed resist film is improved, the polycyclic aliphatic saturated hydrocarbon group and the polycyclic aliphatic unsaturated hydrocarbon group are used. Preferably, a polycyclic aliphatic saturated hydrocarbon group is more preferable, among which a bicyclo [2.2.1] heptenediyl group, a bicyclo [2.2.2] octanediyl group and a tricyclo [5.2.1.0] are preferable. ^2,6 ] Decandyl group and adamantandiyl group are more preferable, and adamantandiyl group is particularly preferable.

When the divalent cyclic hydrocarbon group of Ya is an aromatic cyclic hydrocarbon group, the aromatic cyclic hydrocarbon group may be composed of an aromatic hydrocarbon ring such as benzene, biphenyl, fluorene, naphthalene, anthracene, or phenanthrene. Examples include groups excluding two hydrocarbon atoms.
Specifically, the aromatic cyclic hydrocarbon group is a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring (arylene group); a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring (arylene). A group in which one of the hydrogen atoms of the group) is substituted with a substituent can be mentioned.

Further, the cyclic hydrocarbon group formed by Xa together with Ya may have a substituent. Examples of such substituents include -R ^P1 , -R ^P2 -O-R ^P1 , -R ^P2 -CO-R ^P1 , -R ^P2 -CO-OR ^P1 , -R ^P2 -O-CO-R. Examples thereof include ^P1 , -R ^P2- OH, -R ^P2- CN or -R ^P2- COOH (hereinafter, these substituents are collectively referred to as "Ra ⁰⁴ "). Here, ^RP1 is a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, a monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a monovalent aromatic group having 6 to 30 carbon atoms. It is a group hydrocarbon group. In addition, ^RP2 is a single bond, a divalent chain saturated hydrocarbon group having 1 to 10 carbon atoms, a divalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a divalent product having 6 to 30 carbon atoms. It is an aromatic hydrocarbon group of. However, a chain saturated hydrocarbon group R ^P1 and R ^P2, some or all of the hydrogen atoms included in the aliphatic cyclic saturated hydrocarbon group and aromatic hydrocarbon group may be substituted with a fluorine atom. The aliphatic cyclic hydrocarbon group may have one or more of the above-mentioned substituents alone, or may have one or more of the above-mentioned substituents.

Examples of the monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms represented by Ra ^{01 to} Ra ⁰³ include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group and a heptyl group. , Octyl group, decyl group and the like.
Examples of the monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms represented by Ra ^{01 to} Ra ⁰³ include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group and a cyclooctyl group. Monocyclic aliphatic saturated hydrocarbon groups such as groups, cyclodecyl groups and cyclododecyl groups; bicyclo [2.2.2] octanyl group, tricyclo [5.2.1.02,6] decanyl group, tricyclo [3. Examples thereof include a polycyclic aliphatic saturated hydrocarbon group such as 3.1.13,7] decanyl group, tetracyclo [6.2.1.13, 6.02,7] dodecanyl group and adamantyl group.
Among these, a hydrogen atom and a monovalent chain saturated hydrocarbon group having 1 to 10 carbon atoms are preferable from the viewpoint of easiness of synthesizing the monomer compound giving the structural unit (a0), and among them, the hydrogen atom. , Methyl group and ethyl group are more preferable, and hydrogen atom is particularly preferable.

Examples of the substituents of the chain saturated hydrocarbon group and the aliphatic cyclic saturated hydrocarbon group represented by Ra ^{01 to} Ra ⁰³ include the same groups as those exemplified as Ra ⁰⁴ described above.

Examples of the group containing a carbon-carbon double bond formed by two or more of Ra ^{01 to} Ra ⁰³ bonding to each other to form a cyclic structure include a cyclopentenyl group, a cyclohexenyl group, a methylcyclopentenyl group, and a methylcyclo. Examples thereof include a hexenyl group, a cyclopentylidene etenyl group, and a cyclohexylidene etenyl group. Among them, a cyclopentenyl group, a cyclohexenyl group, and a cyclopentylideneetenyl group are preferable from the viewpoint of easiness of synthesizing the monomer compound giving the structural unit (a0).

Examples of the structural unit (a0) include structural units represented by the following general formulas (a0-1-1) to (a0-1-7), respectively.

Description of the above formula (a0-1-1) ~ (a0-1-7) during the description of R and ^Ra 01 ^{to Ra 03} may, R and ^Ra 01 ^{to Ra 03} in formula (a0-1) Is similar to.
The description of Ra ⁰⁴ is the same as described above, and n2 is an integer of 0 to 3. In the above formula (a0-1-1), n1 is an integer of 1 to 4.

Among these, the structural unit represented by the general formula (a0-1-1) or the structural unit represented by the general formula (a0-1-2) is preferable. When the polymer compound contained in the resist composition of the present invention has a structural unit (a0-1-1) containing a cycloalkane skeleton, the molecule generated from the acid dissociative group is easily volatilized by the dissociation reaction. It is less likely to remain in the resist film. As a result, the diffusion length of the acid can be more optimized by reducing the plasticity of the resist film, so that the pattern forming property and the LWR performance of the radiation-sensitive resin composition are improved.

Specific examples of the structural units represented by the general formula (a0-1-1) will be described below.

In the above formulas (1-1-1) to (1-1-12), the description regarding R is the same as the description regarding R in the above formula (a0-1).
Among these, the viewpoint that the acid diffusion length in the resist film becomes shorter, the pattern forming property and the LWR performance of the radiation-sensitive resin composition are further improved, and the synthesis of the monomer compound giving the structural unit (a0) is easy From the viewpoint of sex, structural units represented by the above formulas (1-1-1) to (1-1-4) are preferable.

Further, when the polymer compound contained in the resist composition of the present invention has a structural unit represented by the general formula (a0-1-2), the adamantane skeleton is directly bonded to the ester group and has acid dissociation property. Since the ease of dissociation of the group is further increased, the PEB temperature can be further lowered, and the pattern forming property, LWR performance, scum suppressing property, and bridge defect suppressing property of the resist composition are further improved. Further, in the unexposed portion, the adamantane skeleton remains in the side chain even after alkaline development, and the rigidity of the polymer is maintained. As a result, the obtained resist film can exhibit excellent etching resistance in the etching step after development.

Specific examples of the structural units represented by the general formula (a0-1-2) will be described below.

In the above formulas (1-2-1) to (1-2-9), R is a hydrogen atom, a fluorine atom, a methyl group or a trifluoromethyl group. Among these, the structure represented by the above formula (1-2-1) from the viewpoint of the ease of dissociation of the acid dissociative group and the viewpoint of the ease of synthesizing the monomer compound giving the structural unit (a0). The unit is preferred.

Specific examples of the structural units represented by the general formulas (a0-1-3) to (a0-1-6) will be described below.

Specific examples of the structural units represented by the general formula (a0-1-7) will be described below.

The ratio of the constituent unit (a0) in the component (A) is preferably 50 to 80 mol%, more preferably 10 to 75 mol%, and 10 to 70 mol% with respect to all the constituent units constituting the component (A). Is even more preferable. By setting the value to the lower limit or higher, the lithographic characteristics such as sensitivity, resolution, and LWR are also improved. Further, by setting the value to the upper limit or less, it is possible to balance with other constituent units.

(Constituent unit (a9))
In the present invention, the component (A) preferably has a structural unit (a9).
As the structural unit (a9), a structural unit represented by the following general formula (a9-1) is preferable.

［式中、Ｒは前記と同様であり、Ｙａ^９１は単結合または２価の連結基であり、Ｒ^９１は置換基を有していてもよい炭化水素基であり、Ｙａ^９２は２価の連結基である。］

[In the formula, R is the same as above, Ya ⁹¹ is a single bond or divalent linking group, R ⁹¹ is a hydrocarbon group which may have a substituent, and Ya ⁹² is divalent. It is a linking group. ]

In the above formula (a9-1), the divalent linking group in Ya ⁹¹ may be the same as the divalent linking group of Ya ²¹ in the formula (a2-1) described later. Ya ⁹¹ is preferably a single bond.
In the formula (a9-1), the divalent linking group in Ya ⁹² is the same as the divalent linking group in Ya ^{91, and} the divalent linking group of Ya ²¹ in the formula (a2-1) described later. Similar things can be mentioned. Among them, in the divalent linking group in Ya ⁹² in the formula (a9-1), the divalent hydrocarbon group which may have a substituent is a linear or branched aliphatic hydrocarbon. The group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, further preferably 1 to 4 groups, and most preferably 1 to 3 carbon atoms.
As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specifically, a methylene group [−CH ₂ −], an ethylene group [− (CH ₂ ) ₂ −], and a trimethylene group [ − (CH ₂ ) ₃ −], tetramethylene group [− (CH ₂ ) ₄ −], pentamethylene group [− (CH ₂ ) ₅ −] and the like can be mentioned.
As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, and specifically, −CH (CH ₃ ) −, −CH (CH ₂ CH ₃ ) −, −C (CH ₃ ). Alkylmethyl groups such as ₂ −, −C (CH ₃ ) (CH ₂ CH ₃ ) −, −C (CH ₃ ) (CH ₂ CH ₂ CH ₃ ) −, −C (CH ₂ CH ₃ ) ₂ −, etc.; − CH (CH ₃ ) CH _2- , -CH (CH ₃ ) CH (CH ₃ )-, -C (CH ₃ ) ₂ CH _2- , -CH (CH ₂ CH ₃ ) CH _2- , -C (CH ₂₎ CH ₃ ) _2- CH ₂ -etc. Alkylethylene groups; -CH (CH ₃ ) CH ₂ CH _2- , -CH ₂ CH (CH ₃ ) CH ₂ -etc. Alkylmethyl group; -CH (CH ₃ ) Examples thereof include alkylalkylene groups such as alkyltetramethylene groups such as CH ₂ CH ₂ CH ₂ − and −CH ₂ CH (CH ₃ ) CH ₂ CH ₂ −. As the alkyl group in the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferable.

Further, in the divalent linking group in Ya ⁹² in the formula (a9-1), the divalent linking group which may have a hetero atom is -O-, -C (= O) -O-. , -C (= O)-, -OC (= O) -O-, -C (= O) -NH-, -NH-, -NH-C (= NH)-(H is an alkyl group, with a substituent such as an acyl group which may be _{substituted), -. S -, -} S (= O) 2 -, - S (= O) 2 -O -, - C (= S) -, the formula ^{-Y 21 -O-Y 22 -,} - Y 21 -O -, - Y 21 -C (= O) -O -, - C (= O) -O - Y 21, [Y 21 -C (= ^{_{O) -O] m '-Y 22}} - or ^{-Y 21 -O-C (= O} ) -Y 22 - group [wherein represented ^{by, Y 21} and ^{Y 22} each independently have a substituent It is a divalent hydrocarbon group which may be used, O is an oxygen atom, and m'is an integer of 0 to 3. ] Etc. can be mentioned. Of these, −C (= O) − and −C (= S) − are preferable.

In the formula (a9-1), examples of the hydrocarbon group in R ⁹¹ include an alkyl group, a monovalent alicyclic hydrocarbon group, an aryl group, and an aralkyl group.
The alkyl group in R ⁹¹ preferably has 1 to 8 carbon atoms, more preferably 1 to 6 carbon atoms, further preferably 1 to 4 carbon atoms, and may be linear or branched. Specifically, a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, an octyl group and the like are preferable.
The monovalent alicyclic hydrocarbon group in R ⁹¹ preferably has 3 to 20 carbon atoms, more preferably 3 to 12 carbon atoms, and may be a polycyclic type or a monocyclic type. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing one or more hydrogen atoms from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclobutane, cyclopentane, and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing one or more hydrogen atoms from a polycycloalkane, and the polycycloalkane is preferably one having 7 to 12 carbon atoms, specifically. Examples thereof include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.
The aryl group in R ⁹¹ preferably has 6 to 18 carbon atoms, more preferably 6 to 10 carbon atoms, and specifically preferably a phenyl group.
The arylyl group in R ⁹¹ is preferably an aralkyl group having 7 to 10 carbon atoms, and the aralkyl group having 7 to 10 carbon atoms includes a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group and a 1-naphthyl group. Arylalkyl groups such as an ethyl group and a 2-naphthylethyl group can be mentioned.
The hydrocarbon group in R ⁹¹ preferably has a part or all of the hydrogen atom of the hydrocarbon group substituted with a fluorine atom, and 30 to 100% of the hydrogen atom of the hydrocarbon group is substituted with a fluorine atom. Is more preferable. Of these, it is particularly preferable that all the hydrogen atoms of the above-mentioned alkyl group are perfluoroalkyl groups substituted with fluorine atoms.

The hydrocarbon group in R ⁹¹ may have a substituent. Examples of the substituent include a halogen atom, an oxo group (= O), a hydroxyl group (-OH), an amino group (-NH ₂ ), -SO _2- NH _{2 and the} like. Further, a part of the carbon atom constituting the hydrocarbon group may be substituted with a substituent containing a hetero atom. Substituents containing the heteroatom include -O-, -NH-, -N =, -C (= O) -O-, -S-, -S (= O) _2-, -S (= O). ) _2- O- can be mentioned.
In R ⁹¹ , examples of the hydrocarbon group having a substituent include lactone-containing cyclic groups represented by the above general formulas (a2-r-1) and to (a2-r-7), respectively.

In ^{R 91,} the hydrocarbon group having a substituent, -SO ₂ respectively represented by below general formula (a5-r-1) ~ (a5-r-4) - containing cyclic group; the following chemical formula Examples thereof include a substituted aryl group represented by, and a monovalent heterocyclic group. In the following formula, "*" indicates a bond with Ya ⁹² .

Specific examples of the structural units represented by the general formula (a9-1) are shown below. In the following formula, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

The structural unit represented by the general formula (a9-1) is preferably the structural unit represented by the following general formula (a9-1-1).

［式中、Ｒは前記と同様であり、Ｙａ^９１は単結合または２価の連結基であり、Ｒ^９１は置換基を有していてもよい炭化水素基であり、Ｒ^９２は酸素原子又は硫黄原子である。］

[In the formula, R is the same as above, Ya ⁹¹ is a single bond or divalent linking group, R ⁹¹ is a hydrocarbon group which may have a substituent, and R ⁹² is an oxygen atom or It is a sulfur atom. ]

In the general formula (a9-1-1), the description of Ya ⁹¹ , R ⁹¹ , and R is the same as described above. Further, R ⁹² is an oxygen atom or a sulfur atom.

Specific examples of the structural units represented by the general formula (a9-1-1) are shown below. In the following formula, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

The structural unit (a9) contained in the component (A) may be one kind or two or more kinds.
When the component (A) has a constituent unit (a9), the ratio of the constituent unit (a9) is preferably 1 to 40 mol% with respect to the total of all the constituent units constituting the component (A). 3 to 30 mol% is more preferable, and 10 to 30 mol% is particularly preferable. By setting the ratio of the structural unit (a9) to the lower limit value or more, the lithography characteristics such as development characteristics and EL margin are improved, and by setting the ratio to the upper limit value or less, it becomes easier to balance with other structural units.

(Constituent unit (a10))
In the present invention, the component (A) preferably has a structural unit (a10) represented by the following general formula (a10-1).

［一般式（ａ１０−１）中、Ｒ^ｓｔは水素原子又はメチル基を表し、Ｒ^００１は水酸基又は炭素数１〜５のアルキル基を表し、ｍ_００は０または１〜７の整数を表す。ｎは０又は１である。］

[In the general formula (a10-1), R ^st represents a hydrogen atom or a methyl group, R ⁰⁰¹ represents a hydroxyl group or an alkyl group having 1 to 5 carbon atoms, and m ₀₀ represents an integer of 0 or 1 to 7. n is 0 or 1. ]

In the general formula (a10-1), R ^st represents a hydrogen atom or a methyl group. ^R001 represents a hydroxyl group or an alkyl group having 1 to 5 carbon atoms. A linear or branched alkyl group having 1 to 5 carbon atoms is preferable, and a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, a neopentyl group and the like are preferable. Can be mentioned. Industrially, a methyl group or an ethyl group is preferable. m ₀₀ represents an integer of 0 or 1-7. n is 0 or 1.

The structural unit (a10) may be a structural unit represented by any of the following general formulas (a10) -1 to (a10) -4, and a structural unit containing a hydroxystyrene skeleton is preferable, and the following general formula is used. The structural unit represented by (a10) -1 is more preferable.

［一般式（ａ１０）−１〜（ａ１０）−４中、Ｒ^ｓｔは水素原子またはメチル基を表し、Ｒ^０１は炭素数１〜５のアルキル基を表し、ｍ_０１は１〜５の整数を表し、ｍ_０２は、０または１〜７の整数である。］

[In the general formula (a10) -1 to (a10) -4, R ^st represents a hydrogen atom or a methyl group, R ⁰¹ represents an alkyl group having 1 to 5 carbon atoms, and m ₀₁ represents an integer of 1 to 5. Represented, m ₀₂ is an integer of 0 or 1-7. ]

In the general formulas (a10) -1 to (a10) -4, R ^st is a hydrogen atom or a methyl group, and is preferably a hydrogen atom.
In the general formula (a10) -1 or (a10) -2, m ₀₁ is an integer of 1 to 5. Of these, m ₀₁ is preferably 1 to 3, and particularly preferably 1.
In the above general formula (a10) -1, the position of the hydroxyl group may be any of the o-position, the m-position, and the p-position, but m is 1 because it is easily available and inexpensive. Moreover, those having a hydroxyl group at the p-position are preferable. When m ₀₁ is 2 or 3, any substitution position can be combined.

In the above general formula (a10) -2 or (a10) -4, R ⁰¹ is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and is preferably a methyl group, an ethyl group, a propyl group, an isopropyl group, or n-. Examples thereof include a butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group. Industrially, a methyl group or an ethyl group is preferable.

In the general formula (a10) -3 or (a10) -4, the above m ₀₂ is an integer of 0 or 1 to 7. Of these, m ₀₂ is preferably 0 or 1-3, more preferably 0 or 1, and particularly preferably industrially 0.
When m ₀₂ is 1, the replacement position of R ⁰¹ may be any of the o-position, m-position, and p-position, and when m ₀₂ is 2 or 3, any substitution is performed. Positions can be combined.

The structural unit (a10) contained in the component (A) may be one kind or two or more kinds.
When the component (A) has a constituent unit (a10), the ratio of the constituent unit (a10) is preferably 1 to 60 mol% with respect to the total of all the constituent units constituting the component (A). More preferably 10 to 50 mol%. By setting the ratio of the structural unit (a10) to the lower limit value or more, the lithography characteristics such as development characteristics and EL margin are improved, and by setting the ratio to the upper limit value or less, it becomes easier to balance with other structural units.

In the present invention, (A) component, further, the structural unit containing an acid decomposable group that exhibits increased polarity by the action of an acid (hereinafter sometimes referred to as "structural unit (a1)".) _- SO 2 - containing A structural unit derived from an acrylic acid ester containing a cyclic group, a lactone-containing cyclic group, a carbonate-containing cyclic group or another heterocyclic group (hereinafter, may be referred to as “constituent unit (a2)”). A structural unit containing a polar group-containing aliphatic hydrocarbon group (hereinafter, may be referred to as “constituent unit (a3)”), a structural unit containing an acid non-dissociable cyclic group (hereinafter, “constituent unit (a4)””. It may have.). Among them, it is preferable to have a structural unit (a2).

(Structural unit (a1))
The structural unit (a1) is a structural unit containing an acid-degradable group whose polarity is increased by the action of an acid.
An "acid-degradable group" is a group having an acid-degradable property in which at least a part of the bonds in the structure of the acid-degradable group can be cleaved by the action of an acid.
Examples of the acid-degradable group whose polarity is increased by the action of an acid include a group which is decomposed by the action of an acid to produce a polar group.
Examples of the polar group include a carboxy group, a hydroxyl group, an amino group, a sulfo group _(-SO 3 H) and the like. Among these, a polar group containing −OH in the structure (hereinafter, may be referred to as “OH-containing polar group”) is preferable, a carboxy group or a hydroxyl group is preferable, and a carboxy group is particularly preferable.
More specific examples of the acid-degradable group include a group in which the polar group is protected by an acid dissociative group (for example, a group in which a hydrogen atom of an OH-containing polar group is protected by an acid dissociative group).
Here, the "acid dissociative group" is
(I) A group having acid dissociation that allows the bond between the acid dissociating group and an atom adjacent to the acid dissociating group to be cleaved by the action of an acid, or a group having acid dissociation.
(Ii) A group capable of cleaving the bond between the acid dissociative group and an atom adjacent to the acid dissociative group by further decarboxylation after the partial bond is cleaved by the action of the acid. ,
Refers to both.
The acid dissociable group constituting the acid-degradable group needs to be a group having a lower polarity than the polar group produced by the dissociation of the acid-dissociable group, whereby the acid-dissociable group due to the action of the acid. When is dissociated, a polar group having a higher polarity than the acid dissociative group is generated and the polarity is increased. As a result, the polarity of the entire component (A1) increases. As the polarity increases, the solubility in the developer changes relatively, and when the developer is an organic developer, the solubility decreases.

The acid dissociative group is not particularly limited, and those previously proposed as an acid dissociative group of the base resin for a chemically amplified resist can be used.
Among the above polar groups, the acid dissociable group that protects the carboxy group or the hydroxyl group includes, for example, an acid dissociative group represented by the following general formula (a1-r-1) (hereinafter, for convenience, “acetal-type acid dissociability”. (Sometimes called "group").

［式中、Ｒａ’^１、Ｒａ’^２は水素原子またはアルキル基、Ｒａ’^３は炭化水素基、Ｒａ’^３は、Ｒａ’^１、Ｒａ’^２のいずれかと結合して環を形成してもよい。＊は結合手を意味する。］

Wherein, Ra ^'1, Ra' ² represents a hydrogen atom or an alkyl group, Ra ^'3 is a hydrocarbon group, Ra' ³ is, Ra ^'1, Ra' ² of bonded either to form a ring Good. * Means a bonder. ]

Wherein (a1-r-1), as the Ra ^'1, Ra' ² alkyl groups, in the description of the α-substituted acrylic acid esters, mentioned as α-position substituent which may be bonded to the carbon atoms of Similar to the alkyl group, a methyl group or an ethyl group is preferable, and a methyl group is most preferable.

The ra ^'3 hydrocarbon group is preferably an alkyl group having 1 to 20 carbon atoms, the alkyl group is more preferably 1 to 10 carbon atoms; preferably a linear or branched alkyl group, specifically, , Methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, 1,1-dimethylethyl group, 1,1-diethylpropyl group Examples thereof include a 2,2-dimethylpropyl group and a 2,2, -dimethylbutyl group.

If Ra ^'3 is a cyclic hydrocarbon group may be aliphatic or aromatic and may be a polycyclic, and may be monocyclic. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing one hydrogen atom from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 8 carbon atoms, and specific examples thereof include cyclopentane, cyclohexane, and cyclooctane. As the polycyclic alicyclic hydrocarbon group, a group obtained by removing one hydrogen atom from polycycloalkane is preferable, and the polycycloalkane preferably has 7 to 12 carbon atoms, and specifically, adamantane. , Norbornane, isobornane, tricyclodecane, tetracyclododecane and the like.

In the case of an aromatic hydrocarbon group, the aromatic ring contained is specifically an aromatic hydrocarbon ring such as benzene, biphenyl, fluorene, naphthalene, anthracene, phenanthrene; the carbon atom constituting the aromatic hydrocarbon ring. Aromatic heterocycles partially substituted with heteroatoms; etc. Examples of the hetero atom in the aromatic heterocycle include an oxygen atom, a sulfur atom, a nitrogen atom and the like.
Specifically, the aromatic hydrocarbon group is a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring (aryl group); a group in which one of the hydrogen atoms of the aryl group is substituted with an alkylene group (for example). , Arylalkyl groups such as benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, 2-naphthylethyl group); and the like. The alkylene group (alkyl chain in the arylalkyl group) preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon atom.

Ra ^'3 is, ra' ^1, if ra ^'2 of bonded either to form a ring, a cyclic group, 4- to 7-membered ring is preferred, 4 to 6-membered ring is more preferable. Specific examples of the cyclic group include a tetrahydropyranyl group and a tetrahydrofuranyl group.

Among the above polar groups, examples of the acid dissociable group that protects the carboxy group include acid dissociative groups represented by the following general formula (a1-r-2) (the following formula (a1-r-2). ), Which is composed of an alkyl group, may be hereinafter referred to as a "tertiary alkyl ester type acid dissociable group" for convenience).

［式中、Ｒａ’^４〜Ｒａ’^６は炭化水素基であり、Ｒａ’^５、Ｒａ’^６は互いに結合して環を形成してもよい。＊は結合手を意味する。］

Wherein, Ra ^'4 ~Ra' ⁶ is a hydrocarbon group, Ra ^'5, Ra' ⁶ may be bonded to each other to form a ring. * Means a bonder. ]

Examples of the hydrocarbon group Ra ^'4 ~Ra' ⁶ include the same as the Ra ^'3. Ra ^'4 is preferably an alkyl group having 1 to 5 carbon atoms. Ra If ^'5, Ra' ⁶ are bonded to each other to form a ring, a group represented by the following general formula (a1-r2-1).
On the other hand, Ra ^'4 ~Ra' ⁶ are not bonded to each other, when an independent hydrocarbon groups include groups represented by the following general formula (a1-r2-2).

［式中、Ｒａ’^１０は炭素数１〜１０のアルキル基、Ｒａ’^１１はＲａ’^１０が結合した炭素原子と共に脂肪族環式基を形成する基、Ｒａ’^１２〜Ｒａ’^１４は、それぞれ独立に炭化水素基を示す。＊は結合手を意味する。］

Wherein, Ra ^'10 is an alkyl group having 1 to 10 carbon atoms, Ra' ¹¹ is' group to form an aliphatic cyclic group together with the carbon atom ^{to which 10} are bonded, Ra 'Ra ¹² to Ra' ¹⁴ each Independently shows a hydrocarbon group. * Means a bonder. ]

Wherein (a1-r2-1), Ra 'alkyl group of the alkyl group having 1 to 10 carbon atoms ^10, Ra in formula (a1-r-1)' a linear or branched alkyl group of ³ The groups listed as are preferred. Wherein (a1-r2-1), Ra 'aliphatic cyclic ^{group 11} is configured, Ra in formula (a1-r-1)' group listed as a cyclic alkyl group of ³ is preferred.

Wherein (a1-r2-2), it is preferable that Ra is ^'12 and Ra' ¹⁴ each independently represents an alkyl group having 1 to 10 carbon atoms, the alkyl group, Ra in formula (a1-r-1) The group listed as the linear or branched alkyl group of ' ³ is more preferable, the linear alkyl group having 1 to 5 carbon atoms is more preferable, and the methyl group or the ethyl group is particularly preferable. ..
Wherein (a1-r2-2) that, Ra ^'13 has the formula (a1-r-1) in the Ra' ³ of the illustrated linear hydrocarbon group, branched or cyclic alkyl group Is preferable. Among these, it is more preferably a group listed as a cyclic alkyl group of Ra ^'3.

Specific examples of the above formula (a1-r2-1) are given below. In the following formula, "*" indicates a bond.

Specific examples of the above formula (a1-r2-2) are given below.

Among the polar groups, the acid dissociative group that protects the hydroxyl group includes, for example, an acid dissociative group represented by the following general formula (a1-r-3) (hereinafter, for convenience, “tertiary alkyloxycarbonylic acid”. (Sometimes referred to as a dissociative group)).

［式中、Ｒａ’^７〜Ｒａ’^９はアルキル基を示す。］

Wherein, Ra ^'7 ~Ra' ⁹ is an alkyl group. ]

Wherein (a1-r-3), Ra '7 ~Ra' 9 is preferably an alkyl group having 1 to 5 carbon atoms, 1 to 3 is more preferable.
The total carbon number of each alkyl group is preferably 3 to 7, more preferably 3 to 5, and most preferably 3 to 4.

The structural unit (a1) is a structural unit derived from an acrylic acid ester in which a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent, and the polarity is increased by the action of an acid. A structural unit containing a degradable group; a structural unit in which at least a part of hydrogen atoms in a hydroxyl group of a structural unit derived from a hydroxystyrene or a hydroxystyrene derivative is protected by a substituent containing the acid-degradable group; vinyl benzoic acid or Examples thereof include a structural unit in which at least a part of hydrogen atoms in -C (= O) -OH, which is a structural unit derived from a vinyl benzoic acid derivative, is protected by a substituent containing the acid-degradable group.

Among the above, the structural unit (a1) is preferably a structural unit derived from an acrylic acid ester in which a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent.
As the structural unit (a1), a structural unit represented by the following general formula (a1-1) or (a1-2) is preferable.

［式中、Ｒは水素原子、炭素数１〜５のアルキル基または炭素数１〜５のハロゲン化アルキル基である。Ｖａ^１はエーテル結合、ウレタン結合、又はアミド結合を有していてもよい２価の炭化水素基であり、ｎ_ａ１は０〜２であり、
Ｒａ^１は上記式（ａ１−ｒ−１）〜（ａ１−ｒ−２）で表される酸解離性基である。Ｗａ^１はｎ_ａ２＋１価の炭化水素基であり、ｎ_ａ２は１〜３であり、Ｒａ^２は上記式（ａ１−ｒ−１）または（ａ１−ｒ−３）で表される酸解離性基である。］

[In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or an alkyl halide group having 1 to 5 carbon atoms. Va ¹ is a divalent hydrocarbon group that may have an ether bond, a urethane bond, or an amide bond, and na ₁ is 0 to 2.
Ra ¹ is an acid dissociative group represented by the above formulas (a1-r-1) to (a1-r-2). Wa ¹ is a n _a2 + 1 valent hydrocarbon group, n a ₂ is 1 to 3, and Ra ² is an acid dissociative group represented by the above formula (a1-r-1) or (a1-r-3). It is a group. ]

In the general formula (a1-1), the alkyl group having 1 to 5 carbon atoms is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specifically, a methyl group, an ethyl group, or the like. Examples thereof include propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group and the like. The alkyl halide group having 1 to 5 carbon atoms is a group in which a part or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like, and a fluorine atom is particularly preferable.
As R, a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a fluorinated alkyl group having 1 to 5 carbon atoms is preferable, and a hydrogen atom or a methyl group is most preferable from the viewpoint of industrial availability.
The hydrocarbon group of Va ¹ may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group. Aliphatic hydrocarbon groups mean hydrocarbon groups that do not have aromaticity. The aliphatic hydrocarbon group as the divalent hydrocarbon group in Va ¹ may be saturated or unsaturated, and is usually preferably saturated.
More specific examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group having a ring in its structure, and the like.
Examples of Va ¹ include those in which the divalent hydrocarbon group is bonded via an ether bond, a urethane bond, or an amide bond.

The linear or branched aliphatic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, further preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms.
As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specifically, a methylene group [−CH ₂ −], an ethylene group [− (CH ₂ ) ₂ −], and a trimethylene group [ − (CH ₂ ) ₃ −], tetramethylene group [− (CH ₂ ) ₄ −], pentamethylene group [− (CH ₂ ) ₅ −] and the like can be mentioned.
As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, and specifically, −CH (CH ₃ ) −, −CH (CH ₂ CH ₃ ) −, −C (CH ₃ ). Alkylmethyl groups such as ₂ −, −C (CH ₃ ) (CH ₂ CH ₃ ) −, −C (CH ₃ ) (CH ₂ CH ₂ CH ₃ ) −, −C (CH ₂ CH ₃ ) ₂ −, etc.; − CH (CH ₃ ) CH _2- , -CH (CH ₃ ) CH (CH ₃ )-, -C (CH ₃ ) ₂ CH _2- , -CH (CH ₂ CH ₃ ) CH _2- , -C (CH ₂₎ CH ₃ ) _2- CH ₂ -etc. Alkylethylene groups; -CH (CH ₃ ) CH ₂ CH _2- , -CH ₂ CH (CH ₃ ) CH ₂ -etc. Alkylmethyl group; -CH (CH ₃ ) Examples thereof include alkylalkylene groups such as alkyltetramethylene groups such as CH ₂ CH ₂ CH ₂ − and −CH ₂ CH (CH ₃ ) CH ₂ CH ₂ −. As the alkyl group in the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferable.

As the aliphatic hydrocarbon group containing a ring in the structure, an alicyclic hydrocarbon group (a group obtained by removing two hydrogen atoms from the aliphatic hydrocarbon ring) and an alicyclic hydrocarbon group are linear or branched. Examples thereof include a group bonded to the terminal of a chain-shaped aliphatic hydrocarbon group and a group in which an alicyclic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include the same groups as described above.
The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably 3 to 12 carbon atoms.
The alicyclic hydrocarbon group may be a polycyclic type or a monocyclic type. As the monocyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from a monocycloalkane is preferable. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. As the polycyclic alicyclic hydrocarbon group, a group obtained by removing two hydrogen atoms from polycycloalkane is preferable, and the polycycloalkane preferably has 7 to 12 carbon atoms, specifically, adamantane. , Norbornane, isobornane, tricyclodecane, tetracyclododecane and the like.

The aromatic hydrocarbon group is a hydrocarbon group having an aromatic ring.
The aromatic hydrocarbon group as the divalent hydrocarbon group in Va ¹ preferably has 3 to 30 carbon atoms, more preferably 5 to 30 carbon atoms, further preferably 5 to 20 carbon atoms, and 6 to 20 carbon atoms. 15 is particularly preferable, and 6 to 10 are most preferable. However, the carbon number does not include the carbon number in the substituent.
Specifically, the aromatic ring contained in the aromatic hydrocarbon group is an aromatic hydrocarbon ring such as benzene, biphenyl, fluorene, naphthalene, anthracene, or phenanthrene; a part of carbon atoms constituting the aromatic hydrocarbon ring is heterogeneous. Aromatic heterocycles substituted with atoms; etc. Examples of the hetero atom in the aromatic heterocycle include an oxygen atom, a sulfur atom, a nitrogen atom and the like.
Specifically, the aromatic hydrocarbon group is a group obtained by removing two hydrogen atoms from the aromatic hydrocarbon ring (arylene group); a group obtained by removing one hydrogen atom from the aromatic hydrocarbon ring (aryl group). ) Is an arylalkyl group in which one of the hydrogen atoms is substituted with an alkylene group (for example, a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, a 2-naphthylethyl group, etc.) A group obtained by removing one more hydrogen atom from the aryl group in the group); and the like. The alkylene group (alkyl chain in the arylalkyl group) preferably has 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon atom.

In the formula (a1-2), n _{a2 +1} monovalent hydrocarbon group for Wa ¹ may be an aliphatic hydrocarbon group may be an aromatic hydrocarbon group. The aliphatic hydrocarbon group means a hydrocarbon group having no aromaticity, and may be saturated or unsaturated, and is usually preferably saturated. Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group containing a ring in the structure, and a linear or branched aliphatic hydrocarbon group. Examples thereof include groups in which a ring-containing aliphatic hydrocarbon group is combined in the structure, and specific examples thereof include the same groups as Va ¹ of the above formula (a1-1).
The _na2 + 1 valence is preferably 2 to 4 valence, more preferably 2 or 3 valence.

As the formula (a1-2), a structural unit represented by the following general formula (a1-2-01) is particularly preferable.

In the formula (a1-2-01), Ra ² is an acid dissociative group represented by the above formula (a1-r-1) or (a1-r-3). n _a2 is an integer of 1 to 3, preferably 1 or 2, and more preferably 1. c is an integer of 0 to 3, preferably 0 or 1, and more preferably 1. R is the same as above.
Specific examples of the above formulas (a1-1) and (a1-2) are shown below. In each of the following formulas, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group.

The ratio of the constituent unit (a1) in the component (A) is preferably 1 to 60 mol%, more preferably 5 to 50 mol%, and 10 to 40 mol% with respect to all the constituent units constituting the component (A). Is even more preferable. By setting the value to the lower limit or higher, the lithographic characteristics such as sensitivity, resolution, and LWR are also improved. Further, by setting the value to the upper limit or less, it is possible to balance with other constituent units.

(Structural unit (a2))
In the present invention, (A) component, -SO 2 _- may contain containing cyclic group, a lactone-containing cyclic group, a carbonate-containing cyclic group or the structural unit having these other heterocyclic groups (a2) preferable.
-SO 2 of the structural unit (a2) _- containing cyclic group, a lactone-containing cyclic group, a carbonate-containing cyclic group or heterocyclic group other than these, when used for forming a resist film (A) component , It is effective in improving the adhesion of the resist film to the substrate.
Incidentally, -SO 2 into its structure the aforementioned structural unit (a1) _- if it is intended to include containing cyclic group, a lactone-containing cyclic group, a carbonate-containing cyclic group or heterocyclic group other than these, the structural unit Also corresponds to the constituent unit (a2), but such a constituent unit corresponds to the constituent unit (a1) and does not correspond to the constituent unit (a2).

The structural unit (a2) is preferably a structural unit represented by the following general formula (a2-1).

［式中、Ｒは水素原子、炭素数１〜５のアルキル基又は炭素数１〜５のハロゲン化アルキル基であり、Ｙａ^２１は単結合または２価の連結基であり、Ｌａ^２１は−Ｏ−、−ＣＯＯ−、−ＣＯＮ（Ｒ’）−、−ＯＣＯ−、−ＣＯＮＨＣＯ−又は−ＣＯＮＨＣＳ−であり、Ｒ’は水素原子またはメチル基を示す。ただしＬａ^２１が−Ｏ−の場合、Ｙａ^２１は−ＣＯ−にはならない。Ｒａ^２１は−ＳＯ_２−含有環式基、ラクトン含有環式基、カーボネート含有環式基又はこれら以外の複素環式基である。］

[In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or an alkyl halide group having 1 to 5 carbon atoms, Ya ²¹ is a single bond or a divalent linking group, and La ²¹ is −O. -, -COO-, -CON (R')-, -OCO-, -CONHCO- or -CONHCS-, where R'indicates a hydrogen atom or a methyl group. However, when La ²¹ is −O−, Ya ²¹ is not −CO−. Ra ²¹ is -SO 2 _- containing cyclic group, a lactone-containing cyclic group, a carbonate-containing cyclic group or heterocyclic group other than these. ]

The divalent linking group of Ya ²¹ is not particularly limited, but a divalent hydrocarbon group which may have a substituent, a divalent linking group containing a heteroatom, and the like are preferable.

(Divalent hydrocarbon group which may have a substituent)
The hydrocarbon group as the divalent linking group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.
Aliphatic hydrocarbon groups mean hydrocarbon groups that do not have aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated.
Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group, an aliphatic hydrocarbon group containing a ring in the structure, and the like, and specifically, the formula (a1-) described later. Examples thereof include the groups exemplified by Va ¹ in 1).

The linear or branched aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms substituted with a fluorine atom, a carbonyl group and the like.

As the aliphatic hydrocarbon group containing a ring in the structure, a cyclic aliphatic hydrocarbon group which may contain a substituent containing a hetero atom in the ring structure (two hydrogen atoms are removed from the aliphatic hydrocarbon ring). Group), a group in which the cyclic aliphatic hydrocarbon group is bonded to the terminal of a linear or branched aliphatic hydrocarbon group, and a cyclic aliphatic hydrocarbon group in which the cyclic aliphatic hydrocarbon group is a linear or branched fat. Examples thereof include a group intervening in the middle of the group hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include the same groups as described above.
The cyclic aliphatic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably 3 to 12 carbon atoms.
Specific examples of the cyclic aliphatic hydrocarbon group include the group exemplified by Va ¹ in the above formula (a1-1).
The cyclic aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, an alkyl halide group, a hydroxyl group, a carbonyl group and the like.
As the alkyl group as the substituent, an alkyl group having 1 to 5 carbon atoms is preferable, and a methyl group, an ethyl group, a propyl group, an n-butyl group and a tert-butyl group are most preferable.
As the alkoxy group as the substituent, an alkoxy group having 1 to 5 carbon atoms is preferable, a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, and a tert-butoxy group are preferable, and methoxy. Groups and ethoxy groups are most preferred.
Examples of the halogen atom as the substituent include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like, and a fluorine atom is preferable.
Examples of the alkyl halide group as the substituent include a group in which a part or all of the hydrogen atom of the alkyl group is substituted with the halogen atom.
The cyclic aliphatic hydrocarbon group may be substituted with a substituent containing a hetero atom as a part of the carbon atom constituting the ring structure. The substituent containing a hetero atom, -O -, - C (= O) -O -, - S -, - S (= O) 2 -, - S (= O) 2 -O- are preferred.

Specific examples of the aromatic hydrocarbon group as the divalent hydrocarbon group include the group exemplified by Va ¹ in the above formula (a1-1).
In the aromatic hydrocarbon group, the hydrogen atom contained in the aromatic hydrocarbon group may be substituted with a substituent. For example, the hydrogen atom bonded to the aromatic ring in the aromatic hydrocarbon group may be substituted with a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, an alkyl halide group, a hydroxyl group and the like.
As the alkyl group as the substituent, an alkyl group having 1 to 5 carbon atoms is preferable, and a methyl group, an ethyl group, a propyl group, an n-butyl group and a tert-butyl group are most preferable.
Examples of the alkoxy group, halogen atom and alkyl halide group as the substituent include those exemplified as the substituent for substituting the hydrogen atom of the cyclic aliphatic hydrocarbon group.

(Divalent linking group containing heteroatom)
The hetero atom in the divalent linking group including the hetero atom is an atom other than the carbon atom and the hydrogen atom, and examples thereof include an oxygen atom, a nitrogen atom, a sulfur atom and a halogen atom.

When Ya ²¹ is a divalent linking group containing a hetero atom, the preferred linking groups are -O-, -C (= O) -O-, -C (= O)-, and -OC. (= O) -O-, -C (= O) -NH-, -NH-, -NH-C (= NH)-(H may be substituted with a substituent such as an alkyl group or an acyl group. _{.), - S -, -} S (= O) 2 -, - S (= O) 2 -O-, the formula ^{-Y 21 -O-Y 22 -,} - Y 21 -O -, - Y 21 - C (= O) -O -, - C (= O) -O - Y 21, [Y 21 -C (= O) -O] m '-Y 22 - or ^-Y 21 -O-C (= O) -Y 22 ^- group [wherein represented by, Y ²¹ and Y ²² are each independently may be substituted divalent hydrocarbon group, O is an oxygen atom, m'is an integer from 0 to 3. ] Etc. can be mentioned.
When the divalent linking group containing a hetero atom is -C (= O) -NH-, -NH-, -NH-C (= NH)-, the H is a substituent such as an alkyl group or an acyl group. It may be replaced. The substituent (alkyl group, acyl group, etc.) preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and particularly preferably 1 to 5 carbon atoms.
Formula ^{-Y 21 -O-Y 22 -,} - Y 21 -O -, - Y 21 -C (= O) -O -, - C (= O) -O-Y 21, - [Y 21 -C ( _{= O) -O] m '-Y} 22 - or ^{-Y 21 -O-C (= O} ) -Y 22 - ^{in, Y 21} and ^{Y 22} each independently have a substituent It is a good divalent hydrocarbon group. Examples of the divalent hydrocarbon group include those similar to the “divalent hydrocarbon group which may have a substituent” described in the description as the divalent linking group.
As Y ²¹ , a linear aliphatic hydrocarbon group is preferable, a linear alkylene group is more preferable, a linear alkylene group having 1 to 5 carbon atoms is further preferable, and a methylene group or an ethylene group is particularly preferable. preferable.
As Y ²² , a linear or branched aliphatic hydrocarbon group is preferable, and a methylene group, an ethylene group or an alkyl methylene group is more preferable. The alkyl group in the alkylmethylene group is preferably a linear alkyl group having 1 to 5 carbon atoms, preferably a linear alkyl group having 1 to 3 carbon atoms, and most preferably a methyl group.
Formula ^{- [Y 21 -C (= O} ) -O] m '-Y 22 - In the group represented by, m' is an integer of 0 to 3, preferably an integer of 0 to 2, 0 Or 1 is more preferable, and 1 is particularly preferable. In other words, the formula ^- Examples of the group represented by the formula ^{-Y 21 -C (= O) -O} -Y 22 - - [Y 21 -C (= O) -O] m '-Y 22 represented by Groups are particularly preferred. Among them, the formula _{- (CH 2) a '-C} (= O) -O- (CH 2) b' - a group represented by are preferred. In the formula, a'is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, further preferably 1 or 2, and most preferably 1. b'is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, further preferably 1 or 2, and most preferably 1.

In the present invention, Ya ²¹ may be a single bond, an ester bond [-C (= O) -O-], an ether bond (-O-), a linear or branched alkylene group, or a combination thereof. It is preferable to have.

In the formula (a2-1), ^{Ra 21} is -SO ₂ - containing cyclic group, a lactone-containing cyclic group, a heterocyclic group or a carbonate-containing cyclic group.

And _- "-SO 2 containing cyclic group", -SO 2 _- within the ring skeleton thereof shows a cyclic group containing a ring containing, in particular, -SO 2 _- sulfur atom (S) is in A cyclic group that forms part of the cyclic skeleton of the cyclic group. A ring containing −SO ₂ − in its ring skeleton is counted as the first ring, and if it is only the ring, it is a monocyclic group, and if it has another ring structure, it is a polycyclic group regardless of its structure. It is called. The −SO ₂ − containing cyclic group may be monocyclic or polycyclic.
-SO ₂ - containing cyclic group, in particular, -O-SO ₂ - within the ring skeleton cyclic group containing, i.e. -O-SO ₂ - -O-S- medium is a part of the ring skeleton It is preferably a cyclic group containing a sultone ring to be formed. -SO ₂ - containing cyclic group, and more specifically, include groups respectively represented by the following formula (a5-r-1) ~ (a5-r-4).

［式中、Ｒａ’^５１はそれぞれ独立に水素原子、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、水酸基、−ＣＯＯＲ”、−ＯＣ（＝Ｏ）Ｒ”、ヒドロキシアルキル基またはシアノ基であり；Ｒ”は水素原子またはアルキル基であり；Ａ”は酸素原子もしくは硫黄原子を含んでいてもよい炭素数１〜５のアルキレン基、酸素原子または硫黄原子であり、ｎ’は０〜２の整数である。］

Wherein, Ra ^'51 each independently represent a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, hydroxyl group, -COOR - in ", OC (= O) R ", a hydroxyalkyl group or a cyano group Yes; R "is a hydrogen atom or an alkyl group; A" is an alkylene group having 1 to 5 carbon atoms, which may contain an oxygen atom or a sulfur atom, an oxygen atom or a sulfur atom, and n'is 0 to 2. Is an integer of. ]

In the general formulas (a5-r-1) to (a5-r-4), A "is the same as A" in the general formulas (a2-r-1) to (a2-r-7) described later. .. Alkyl group in ra ^'51, an alkoxy group, a halogen atom, a halogenated alkyl group, -COOR ", - OC (= O) R", The hydroxyalkyl group, described below general formula (a2-r-1) ~ ( it is the same as a2-r-7) in the Ra ^'21.

Specific examples of the groups represented by the general formulas (a5-r-1) to (a5-r-4) are given below. "Ac" in the formula indicates an acetyl group.

In the present invention, the structural unit (a2) is -SO ₂ - when containing containing cyclic group, among the above, is preferably a group represented by the formula (a5-r-1), the formula (r-sl -Selected from the group consisting of groups represented by any of (1-1), (r-sl-1-18), (r-sl-3-1) and (r-sl-4-1). It is more preferable to use at least one kind, and the group represented by the chemical formula (r-sl-1-1) is most preferable.

The “lactone-containing cyclic group” refers to a cyclic group containing a ring (lactone ring) containing −OC (= O) − in its cyclic skeleton. The lactone ring is counted as the first ring, and when it has only a lactone ring, it is called a monocyclic group, and when it has another ring structure, it is called a polycyclic group regardless of its structure. The lactone-containing cyclic group may be a monocyclic group or a polycyclic group.
The lactone-containing cyclic group as cyclic hydrocarbon group of R ^1, any can be used without being particularly limited. Specifically, the groups represented by the following general formulas (a2-r-1) to (a2-r-7) can be mentioned. Hereinafter, "*" represents a bond.

［式中、Ｒａ’^２１はそれぞれ独立に水素原子、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、水酸基、−ＣＯＯＲ”、−ＯＣ（＝Ｏ）Ｒ”、ヒドロキシアルキル基またはシアノ基であり；Ｒ”は水素原子またはアルキル基であり；Ａ”は酸素原子もしくは硫黄原子を含んでいてもよい炭素数１〜５のアルキレン基、酸素原子または硫黄原子であり、ｎ’は０〜２の整数であり、ｍ’は０または１である。］

Wherein, Ra ^'21 each independently represent a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, hydroxyl group, -COOR - in ", OC (= O) R ", a hydroxyalkyl group or a cyano group Yes; R "is a hydrogen atom or an alkyl group; A" is an alkylene group having 1 to 5 carbon atoms, which may contain an oxygen atom or a sulfur atom, an oxygen atom or a sulfur atom, and n'is 0 to 2. And m'is 0 or 1. ]

In the general formulas (a2-r-1) to (a2-r-7), A "may contain an oxygen atom (-O-) or a sulfur atom (-S-) and has 1 to 5 carbon atoms. As the alkylene group having 1 to 5 carbon atoms in A ″, a linear or branched alkylene group is preferable, and a methylene group, an ethylene group, an n-propylene group, etc. Examples include an isopropylene group. When the alkylene group contains an oxygen atom or a sulfur atom, specific examples thereof include a group in which -O- or -S- is interposed between the terminal or carbon atom of the alkylene group, for example, -O-CH _{2. -, - CH 2 -O-CH} 2 -, - S-CH 2 -, - CH 2 -S-CH 2 - , and the like. The A ", alkylene group or -O- is preferable of 1 to 5 carbon atoms, more preferably an alkylene group having 1 to 5 carbon atoms, the most preferred .ra ^'21 are each independently a methylene group, an alkyl group, an alkoxy It is a group, a halogen atom, an alkyl halide group, -COOR ", -OC (= O) R", a hydroxyalkyl group or a cyano group.
The alkyl group in ra ^'21, preferably an alkyl group having 1 to 5 carbon atoms.
The alkoxy group in the ra ^'21, preferably an alkoxy group having 1 to 6 carbon atoms.
The alkoxy group is preferably linear or branched. Specifically, groups of the the Ra 'group and an oxygen atom mentioned as the alkyl group in ²¹ (-O-) are linked and the like.
As the halogen atom in ra ^'21, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a fluorine atom is preferable.
'Examples of the halogenated alkyl group for ^21, the Ra' Ra part or all of the hydrogen atoms of the alkyl group in ²¹ can be mentioned it has been substituted with the aforementioned halogen atoms. As the alkyl halide group, an alkyl fluorinated group is preferable, and a perfluoroalkyl group is particularly preferable.

Specific examples of the groups represented by the general formulas (a2-r-1) to (a2-r-7) are given below.

In the present invention, the structural unit (a2) is preferably a group represented by the general formula (a2-r-1) or (a2-r-2), respectively, and the chemical formula (r-lc-1-1) or The groups represented by (r-lc-2-7) are more preferable.

The "carbonate-containing cyclic group" refers to a cyclic group containing a ring (carbonate ring) containing -OC (= O) -O- in its cyclic skeleton. The carbonate ring is counted as the first ring, and when it has only a carbonate ring, it is called a monocyclic group, and when it has another ring structure, it is called a polycyclic group regardless of its structure. The carbonate-containing cyclic group may be a monocyclic group or a polycyclic group.
The carbonate ring-containing cyclic group as cyclic hydrocarbon group of R ^1, any can be used without being particularly limited. Specific examples thereof include groups represented by the following general formulas (ax3-r-1) to (ax3-r-3).

［式中、Ｒａ’^ｘ３１はそれぞれ独立に水素原子、アルキル基、アルコキシ基、ハロゲン原子、ハロゲン化アルキル基、水酸基、−ＣＯＯＲ”、−ＯＣ（＝Ｏ）Ｒ”、ヒドロキシアルキル基またはシアノ基であり；Ｒ”は水素原子またはアルキル基であり；Ａ”は酸素原子もしくは硫黄原子を含んでいてもよい炭素数１〜５のアルキレン基、酸素原子または硫黄原子でありｑ’は０または１である。］

[In the formula, ^Ra'x31 is independently a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, an alkyl halide group, a hydroxyl group, -COOR ", -OC (= O) R", a hydroxyalkyl group or a cyano group. Yes; R "is a hydrogen atom or an alkyl group; A" is an alkylene group having 1 to 5 carbon atoms, which may contain an oxygen atom or a sulfur atom, an oxygen atom or a sulfur atom, and q'is 0 or 1. is there. ]

A "in the general formulas (ax3-r-1) to (ax3-r-3) is the same as A" in the general formula (a2-r-1).
Alkyl group in ra ^'31, an alkoxy group, a halogen atom, a halogenated alkyl group, -COOR ", - OC (= O) R", The hydroxyalkyl group, each of the general formulas (a2-r-1) ~ ( a2-r-7) as in the same as those exemplified in the description of the Ra ^'21 of the like.

Specific examples of the groups represented by the general formulas (ax3-r-1) to (ax3-r-3) are given below.

The "heterocyclic group" refers to a cyclic group containing one or more atoms other than carbon in addition to carbon, and is a heterocyclic group listed in (r-hr-1) to (r-hr-16) described later, respectively. Examples include a cyclic group and a nitrogen-containing heterocycle. Examples of the nitrogen-containing heterocyclic group include a cycloalkyl group having 3 to 8 carbon atoms which may be substituted with one or two oxo groups. As the cycloalkyl group, for example, 2,5-dioxopyrrolidine and 2,6-dioxopiperidine are preferable.

The structural unit (a2) contained in the component (A) may be one type or two or more types.
In the present invention, the structural unit (a2), -SO 2 _- is preferably one having a containing cyclic group or a lactone-containing cyclic group, those having a lactone-containing cyclic group are particularly preferred.
When the component (A) has the constituent unit (a2), the ratio of the constituent unit (a2) is preferably 1 to 80 mol% with respect to the total of all the constituent units constituting the component (A). It is more preferably 5 to 70 mol%, further preferably 10 to 65 mol%, and particularly preferably 10 to 60 mol%. By setting it to the lower limit value or more, the effect of containing the constituent unit (a2) can be sufficiently obtained, and by setting it to the upper limit value or less, it is possible to balance with other constituent units, and various lithography characteristics and patterns can be obtained. The shape becomes good.

(Structural unit (a3))
The structural unit (a3) is a structural unit containing a polar group-containing aliphatic hydrocarbon group (however, excluding those corresponding to the above-mentioned structural units (a1) and (a2)).
It is considered that the component (A) having the constituent unit (a3) enhances the hydrophilicity of the component (A) and contributes to the improvement of the resolution.
Examples of the polar group include a hydroxyl group, a cyano group, a carboxy group, a hydroxyalkyl group in which a part of hydrogen atoms of the alkyl group is replaced with a fluorine atom, and the like, and 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 cyclic aliphatic hydrocarbon group (cyclic group). The cyclic group may be a monocyclic group or a polycyclic group, and for example, in the resin for the resist composition for ArF excimer laser, it can be appropriately selected and used from a large number of proposed ones. The cyclic group is preferably a polycyclic group, and more preferably has 7 to 30 carbon atoms.
Among them, a structural unit derived from 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 a group obtained by removing two or more hydrogen atoms from a bicycloalkane, a tricycloalkane, a tetracycloalkane, or the like. Specific examples thereof include groups obtained by removing two or more hydrogen atoms from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Among these polycyclic groups, there are a group in which two or more hydrogen atoms are removed from adamantane, a group in which two or more hydrogen atoms are removed from norbornane, and a group in which two or more hydrogen atoms are removed from tetracyclododecane. Industrially preferable.

The structural unit (a3) is not particularly limited as long as it contains a polar group-containing aliphatic hydrocarbon group, and any unit can be used.
The structural unit (a3) is a structural unit derived from an acrylic acid ester in which a hydrogen atom bonded to a carbon atom at the α-position may be substituted with a substituent and includes a polar group-containing aliphatic hydrocarbon group. Constituent units are preferred.
As the structural unit (a3), 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, it is derived from the hydroxyethyl ester of acrylic acid. When the hydrocarbon group is a polycyclic group, the structural unit represented by the following formula (a3-1), the structural unit represented by the formula (a3-2), and the formula ( The structural unit represented by a3-3) is preferably mentioned.

［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。］

[In the formula, R is the same as above, j is an integer of 1-3, k is an integer of 1-3, t'is an integer of 1-3, and l is an integer of 1-5. And s is an integer of 1-3. ]

In the 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 3- and 5-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 in particular, the hydroxyl group is preferably bonded to the 3-position of the adamantyl group.

In formula (a3-2), k is preferably 1. The cyano group is preferably attached to the 5- or 6-position of the norbornyl group.
In formula (a3-3), t'is preferably 1. l is preferably 1. s is preferably 1. In these, it is preferable that a 2-norbornyl group or a 3-norbornyl group is bonded to the terminal of the carboxy group of acrylic acid. The fluorinated alkyl alcohol is preferably bonded to the 5 or 6 position of the norbornyl group.

The structural unit (a3) contained in the component (A) may be one kind or two or more kinds.
The proportion of the constituent unit (a3) in the component (A) is preferably 5 to 50 mol%, preferably 5 to 40 mol%, based on the total of all the constituent units constituting the base material component (A). More preferably, 5 to 25 mol% is further preferable.
By setting the ratio of the constituent unit (a3) to the lower limit value or more, the effect of containing the constituent unit (a3) can be sufficiently obtained, and by setting it to the upper limit value or less, a balance with other constituent units can be obtained. It will be easier.

(Structural unit (a4))
The structural unit (a4) is a structural unit containing an acid non-dissociative cyclic group. Since the component (A) has the structural unit (a4), the dry etching resistance of the resist pattern to be formed is improved. In addition, the hydrophobicity of the component (A) is increased. The improvement of hydrophobicity is considered to contribute to the improvement of resolution, resist pattern shape, etc., especially in the case of organic solvent development.
The "acid non-dissociative cyclic group" in the structural unit (a4) is contained in the structural unit as it is without dissociation even if the acid acts when an acid is generated from the component (B) described later by exposure. The remaining cyclic group.
As the structural unit (a4), for example, a structural unit derived from an acrylic acid ester containing an acid non-dissociative aliphatic cyclic group is preferable. As the cyclic group, for example, the same ones as those exemplified in the case of the above-mentioned structural unit (a1) can be exemplified, such as for ArF excimer laser, for KrF excimer laser (preferably for ArF excimer laser), and the like. A large number of conventionally known ones used for the base material component of the resist composition of the above can be used.
In particular, at least one selected from a tricyclodecyl group, an adamantyl group, a tetracyclododecyl group, an isobornyl group, and a norbornyl group is preferable in that it is easily available industrially. These polycyclic groups may have a linear or branched alkyl group having 1 to 5 carbon atoms as a substituent.
As the structural unit (a4), specifically, those having the structures of the following general formulas (a4-1) to (a4-7) can be exemplified.

［式中、Ｒ^αは、水素原子、メチル基またはトリフルオロメチル基を示す。］

[In the formula, R ^α represents a hydrogen atom, a methyl group or a trifluoromethyl group. ]

The structural unit (a4) contained in the component (A) may be one kind or two or more kinds.
When the constituent unit (a4) is contained in the component (A), the ratio of the constituent unit (a4) is preferably 1 to 30 mol% with respect to the total of all the constituent units constituting the component (A). More preferably, it is 10 to 20 mol%.

The component (A) is obtained by polymerizing a monomer that induces each structural unit by a known radical polymerization using a radical polymerization initiator such as azobisisobutyronitrile (AIBN) or dimethyl azobisisobutyrate. be able to.
Further, the component (A1), during the polymerization, by using a combination of chain transfer agent such as _{HS-CH 2 -CH 2 -CH 2} -C (CF 3) 2 -OH, end -C (CF ₃ ) _2- OH group may be introduced into the. In this way, the copolymer in which the hydroxyalkyl group in which a part of the hydrogen atom of the alkyl group is replaced with the fluorine atom is introduced can reduce development defects and LER (line edge roughness: non-uniform unevenness of the line side wall). It is effective in reducing the amount of water.

In the present invention, the weight average molecular weight (Mw) (polystyrene conversion standard by gel permeation chromatography) of the component (A) is not particularly limited, and is preferably 1000 to 50000, more preferably 1500 to 30000, and 2000. ~ 20000 is the most preferable. When it is not more than the upper limit value of this range, it has sufficient solubility in a resist solvent to be used as a resist, and when it is more than the lower limit value of this range, the dry etching resistance and the cross-sectional shape of the resist pattern are good.

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

≪Other ingredients≫
In the present embodiment, the resist composition may further contain other components in addition to the component (A) or in addition to the components (A) and (B).
Examples of other components include (D) component, (E) component, (F) component, and (S) component, which will be described later.

Ingredient (D):
In the present embodiment, the resist composition may further contain an acid diffusion control agent component (hereinafter, also referred to as “(D) component”).
The component (D) acts as a quencher (acid diffusion control agent) that traps the acid generated by exposure from the component (B) and the like.
The component (D) in the present embodiment may be a photodisintegrating base (D1) (hereinafter referred to as “component (D1)”) that is decomposed by exposure and loses acid diffusion controllability, and the component (D1). It may be a nitrogen-containing organic compound (D2) (hereinafter, referred to as “(D2) component”) that does not correspond to the above.

-Component (D1) Component By using a resist composition containing the component (D1), it is possible to improve the contrast between the exposed portion and the non-exposed portion when forming a resist pattern.
The component (D1) is not particularly limited as long as it is decomposed by exposure and loses acid diffusion controllability, and is a compound represented by the following general formula (d1-1) (hereinafter, “component (d1-1)”). The compound represented by the following general formula (d1-2) (hereinafter referred to as "(d1-2) component") and the compound represented by the following general formula (d1-3) (hereinafter referred to as "(d1-d1-) component"). 3) One or more compounds selected from the group consisting of "components") are preferable.
The components (d1-1) to (d1-3) do not act as a quencher because they decompose in the exposed portion and lose the acid diffusion controllability (basicity), but act as a quencher in the unexposed portion.

［式中、Ｒｄ^１〜Ｒｄ^４は置換基を有していてもよい環式基、置換基を有していてもよい鎖状のアルキル基、または置換基を有していてもよい鎖状のアルケニル基である。ただし、式（ｄ１−２）中のＲｄ^２における、Ｓ原子に隣接する炭素原子にはフッ素原子は結合していないものとする。Ｙｄ^１は単結合、または２価の連結基である。Ｍ^ｍ＋はそれぞれ独立にｍ価の有機カチオンである。］

[In the formula, Rd ^{1 to} Rd ⁴ have a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain which may have a substituent. Alkyl group of. However, it is assumed that the fluorine atom is not bonded to the carbon atom adjacent to the S atom in Rd ² in the formula (d1-2). Yd ¹ is a single bond or divalent linking group. M ^{m +} are independently m-valent organic cations. ]

{(D1-1) component}
.. In the anion part formula (d1-1), Rd ¹ has a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a substituent. It is a chain alkenyl group which may be used, and examples thereof include the same group as R ¹⁰¹ .
Among these, Rd ¹ may have an aromatic hydrocarbon group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a substituent. Chained hydrocarbon groups are preferred. As the substituent that these groups may have, a hydroxyl group, a fluorine atom or a fluorinated alkyl group is preferable.
As the aromatic hydrocarbon group, a phenyl group or a naphthyl group is more preferable.
The aliphatic cyclic group is more preferably a group obtained by removing one or more hydrogen atoms from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.
As the chain hydrocarbon group, a chain alkyl group is preferable. The chain alkyl group preferably has 1 to 10 carbon atoms, and specifically, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, and a nonyl group. Linear alkyl groups such as groups and decyl groups; 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl group , 2-Ethylbutyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group and other branched alkyl groups;

When the chain-like alkyl group is a fluorinated alkyl group having a fluorine atom or a fluorinated alkyl group as a substituent, the fluorinated alkyl group preferably has 1 to 11 carbon atoms, more preferably 1 to 8 carbon atoms. The alkylated fluorinated group, more preferably from 4 to 4, may contain an atom other than the fluorine atom. Examples of atoms other than fluorine atoms include oxygen atoms, carbon atoms, hydrogen atoms, sulfur atoms, nitrogen atoms and the like.
Rd ¹ is preferably a fluorinated alkyl group in which some or all of the hydrogen atoms constituting the linear alkyl group are substituted with fluorine atoms, and Rd ¹ is a hydrogen atom constituting the linear alkyl group. It is preferable that all of them are fluorinated alkyl groups (linear perfluoroalkyl groups) substituted with fluorine atoms.

A preferable specific example of the anion portion of the component (d1-1) is shown below.

.. In the cation part equation (d1-1), M ^{m +} is an m-valent organic cation.
The organic cation of M ^{m +} is not particularly limited, and examples thereof include the same cations represented by the general formulas (ca-1) to (ca-4), respectively, and the above formula (ca-1-). The cations represented by 1) to (ca-1-63) are preferable.
As the component (d1-1), one type may be used alone, or two or more types may be used in combination.

{(D1-2) component}
.. In the anion part formula (d1-2), Rd ² has a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a substituent. It is a chain alkenyl group which may be present, and examples thereof include the same group as R ¹⁰¹ .
However, it is assumed that the carbon atom adjacent to the S atom in Rd ² does not have a fluorine atom bonded (fluorine-substituted). As a result, the anion of the component (d1-2) becomes an appropriate weak acid anion, and the quenching ability of the component (D) is improved.
Rd ² is preferably an aliphatic cyclic group which may have a substituent, and is a group obtained by removing one or more hydrogen atoms from adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane and the like. (It may have a substituent); It is more preferable that it is a group obtained by removing one or more hydrogen atoms from a camphor or the like.
The hydrocarbon group of Rd ² may have a substituent, and the substituent may be a hydrocarbon group (aromatic hydrocarbon group, aliphatic hydrocarbon group) in Rd ¹ of the above formula (d1-1). Examples include the same substituents that may have.

A preferable specific example of the anion portion of the component (d1-2) is shown below.

· · In the cation part formula (d1-2), M ^{m +} is an m-valent organic cation, which is the same as M ^{m +} in the above formula (d1-1).
As the component (d1-2), one type may be used alone, or two or more types may be used in combination.

{(D1-3) component}
.. In the anion part formula (d1-3), Rd ³ has a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a substituent. It may be a chain alkenyl group, the same as that of R ^101, and is preferably a cyclic group containing a fluorine atom, a chain alkyl group, or a chain alkenyl group. Of these, an alkyl fluorinated group is preferable, and the same group as the alkyl fluorinated group of Rd ¹ is more preferable.

In formula (d1-3), Rd ⁴ may have a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a substituent. It is a chain alkenyl group, and the same group as R ¹⁰¹ can be mentioned.
Of these, an alkyl group, an alkoxy group, an alkenyl group, or a cyclic group which may have a substituent is preferable.
The alkyl group in Rd ⁴ is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, or an isobutyl group. , Tert-Butyl group, pentyl group, isopentyl group, neopentyl group and the like. A part of the hydrogen atom of the alkyl group of Rd ⁴ may be substituted with a hydroxyl group, a cyano group or the like.
The alkoxy group in Rd ⁴ is preferably an alkoxy group having 1 to 5 carbon atoms, and specifically, the alkoxy group having 1 to 5 carbon atoms is a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, or n-. Examples thereof include a butoxy group and a tert-butoxy group. Of these, a methoxy group and an ethoxy group are preferable.

Examples of the alkenyl group in Rd ⁴ include those similar to those in R ^101, and a vinyl group, a propenyl group (allyl group), a 1-methylpropenyl group, and a 2-methylpropenyl group are preferable. These groups may further have an alkyl group having 1 to 5 carbon atoms or an alkyl halide group having 1 to 5 carbon atoms as a substituent.

Examples of the cyclic group in Rd ⁴ include those similar to those in R ¹⁰¹ above, and one or more hydrogen atoms are removed from cycloalkanes such as cyclopentane, cyclohexane, adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. An alicyclic group or an aromatic group such as a phenyl group or a naphthyl group is preferable. When Rd ⁴ is an alicyclic group, the resist composition is well dissolved in an organic solvent, so that the lithography characteristics are improved. Further, when Rd ⁴ is an aromatic group, the resist composition has excellent light absorption efficiency and good sensitivity and lithography characteristics in lithography using EUV or the like as an exposure light source.

In formula (d1-3), Yd ¹ is a single bond or a divalent linking group.
The divalent linking group in Yd ¹ is not particularly limited, but includes a divalent hydrocarbon group (aliphatic hydrocarbon group, aromatic hydrocarbon group) which may have a substituent and a hetero atom 2 Examples include valuation linkage groups. Examples of these are the same as those mentioned in the description of the divalent linking group of Ya ²¹ in the above formula (a2-1).
Yd ¹ is preferably a carbonyl group, an ester bond, an amide bond, an alkylene group, or a combination thereof. The alkylene group is more preferably a linear or branched alkylene group, and even more preferably a methylene group or an ethylene group.

A preferable specific example of the anion portion of the component (d1-3) is shown below.

· · In the cation part formula (d1-3), M ^{m +} is an m-valent organic cation, which is the same as M ^{m +} in the formula (d1-1).
As the component (d1-3), one type may be used alone, or two or more types may be used in combination.

As the component (D1), only one of the above components (d1-1) to (d1-3) may be used, or two or more of them may be used in combination.
The content of the component (D1) is preferably 0.5 to 10 parts by mass, more preferably 0.5 to 8 parts by mass, and 1 to 8 parts by mass with respect to 100 parts by mass of the component (A). It is more preferably parts by mass.
When the content of the component (D1) is at least a preferable lower limit value, particularly good lithography characteristics and a resist pattern shape can be obtained. On the other hand, when it is not more than the upper limit value, the sensitivity can be maintained well and the throughput is also excellent.

The method for producing the above-mentioned components (d1-1) and (d1-2) is not particularly limited, and can be produced by a known method.

The content of the component (D1) is preferably 0.5 to 10.0 parts by mass, and more preferably 0.5 to 8.0 parts by mass with respect to 100 parts by mass of the component (A). , 1.0 to 8.0 parts by mass is more preferable. When it is at least the lower limit of the above range, particularly good lithography characteristics and resist pattern shape can be obtained. When it is not more than the upper limit value of the above range, the sensitivity can be maintained well and the throughput is also excellent.

-Component (D2) The component (D) may contain a nitrogen-containing organic compound component (hereinafter referred to as "component (D2)") that does not correspond to the above component (D1).
The component (D2) is not particularly limited as long as it acts as an acid diffusion control agent and does not correspond to the component (D1), and any known component may be used. Of these, aliphatic amines, particularly secondary aliphatic amines and tertiary aliphatic amines, are preferable.
The aliphatic amine is an amine having one or more aliphatic groups, and the aliphatic group preferably has 1 to 12 carbon atoms.
Examples of the aliphatic amine include amines (alkylamines or alkylalcoholamines) in which at least one hydrogen atom of ammonia NH ₃ is replaced with an alkyl group or a hydroxyalkyl group having 12 or less carbon atoms, or a cyclic amine.
Specific examples of alkylamines and alkylalcohol 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-pentylamine, tri-n-hexylamine , Tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decylamine, tri-n-dodecylamine and other trialkylamines; diethanolamine, triethanolamine, diisopropanolamine, tri Alkyl alcohol amines such as isopropanolamine, di-n-octanolamine and tri-n-octanolamine can be mentioned. Among these, trialkylamines having 5 to 10 carbon atoms are more preferable, and tri-n-pentylamine or tri-n-octylamine is particularly preferable.

Examples of the cyclic amine include a heterocyclic compound containing a nitrogen atom as a hetero atom. The heterocyclic compound may be a monocyclic compound (aliphatic monocyclic amine) or a polycyclic compound (aliphatic polycyclic amine).
Specific examples of the aliphatic monocyclic amine include piperidine and piperazine.
The aliphatic polycyclic amine preferably has 6 to 10 carbon atoms, and specifically, 1,5-diazabicyclo [4.3.0] -5-nonene and 1,8-diazabicyclo [5. 4.0] -7-undecene, hexamethylenetetramine, 1,4-diazabicyclo [2.2.2] octane and the like can be mentioned.

Other aliphatic amines include tris (2-methoxymethoxyethyl) amine, tris {2- (2-methoxyethoxy) ethyl} amine, tris {2- (2-methoxyethoxymethoxy) ethyl} amine, and tris {2. -(1-methoxyethoxy) ethyl} amine, tris {2- (1-ethoxyethoxy) ethyl} amine, tris {2- (1-ethoxypropoxy) ethyl} amine, tris [2- {2- (2-hydroxy) Examples thereof include ethoxy) ethoxy} ethyl] amine and triethanolamine triacetate, and triethanolamine triacetate is preferable.

Further, as the component (D2), an aromatic amine may be used.
Aromatic amines include aniline, pyridine, 4-dimethylaminopyridine, pyrrole, indol, pyrazole, imidazole or derivatives thereof, diphenylamine, triphenylamine, tribenzylamine, 2,6-diisopropylaniline, N-tert-butoxy. Examples thereof include carbonylpyrrolidine.

The component (D2) may be used alone or in combination of two or more.
The component (D2) is usually used in the range of 0.01 to 5.0 parts by mass with respect to 100 parts by mass of the component (A). Within the above range, the shape of the resist pattern, stability over time, and the like are improved.

As the component (D), one type may be used alone, or two or more types may be used in combination.
When the resist composition contains the component (D) in the present embodiment, the component (D) is preferably 0.1 to 15 parts by mass with respect to 100 parts by mass of the component (A), and is 0.3. It is more preferably ~ 12 parts by mass, and further preferably 0.5 to 12 parts by mass.
When it is at least the lower limit of the above range, the lithography characteristics such as LWR are further improved when the resist composition is prepared. Moreover, a better resist pattern shape can be obtained. When it is not more than the upper limit value of the above range, the sensitivity can be maintained well and the throughput is also excellent.

(E) Ingredient:
In the present embodiment, the resist composition contains an organic carboxylic acid, an oxo acid of phosphorus, and a derivative thereof as optional components for the purpose of preventing deterioration of sensitivity, improving the shape of the resist pattern, stability over time, and the like. At least one compound (E) selected from the group consisting of (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 the oxo acid of phosphorus include phosphoric acid, phosphonic acid, phosphinic acid and the like, and among these, phosphonic acid is particularly preferable.
Examples of the derivative of the oxo acid of phosphorus include an ester in which the hydrogen atom of the oxo acid is replaced with a hydrocarbon group, and the hydrocarbon group includes an alkyl group having 1 to 5 carbon atoms and 6 to 6 carbon atoms. Examples include 15 aryl groups.
Examples of the phosphoric acid derivative include phosphoric acid esters such as phosphoric acid di-n-butyl ester and phosphoric acid diphenyl ester.
Examples of the phosphonic acid derivative 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 derivative of phosphinic acid include phosphinic acid ester and phenylphosphinic acid.
As the component (E), one type may be used alone, or two or more types may be used in combination.
The component (E) is usually used in the range of 0.01 to 5.0 parts by mass with respect to 100 parts by mass of the component (A).

(F) component:
In the present embodiment, the resist composition may contain a fluorine additive (hereinafter referred to as "component (F)") in order to impart water repellency to the resist film.
Examples of the component (F) include JP-A-2010-002870, JP-A-2010-032994, JP-A-2010-277043, JP-A-2011-13569, and JP-A-2011-128226. The described fluorine-containing polymer compound can be used.
More specifically, as the component (F), a polymer having a structural unit (f1) represented by the following formula (f1-1) can be mentioned. The polymer is a polymer (copolymer) consisting of only the structural unit (f1) represented by the following formula (f1-1); the structural unit (f1) represented by the following formula (f1-1) and the above. Copolymer with the structural unit (a1); the structural unit (f1) represented by the following formula (f1-1), the structural unit derived from acrylic acid or methacrylic acid, and the structural unit (a1). It is preferably a copolymer. Here, as the structural unit (a1) copolymerized with the structural unit (f1) represented by the following formula (f1-1), 1-ethyl-1-cyclooctyl (meth) acrylate and 2-methyl- 2-adamantyl (meth) acrylate or a structural unit represented by the above formula (a1-2-01) is preferable.

［式中、Ｒは前記同様であり、Ｒｆ^１０２およびＲｆ^１０３はそれぞれ独立して水素原子、ハロゲン原子、炭素数１〜５のアルキル基、又は炭素数１〜５のハロゲン化アルキル基を表し、Ｒｆ^１０２およびＲｆ^１０３は同じであっても異なっていてもよい。ｎｆ^１は１〜５の整数であり、Ｒｆ^１０１はフッ素原子を含む有機基である。］

[In the formula, R is the same as described above, and Rf ¹⁰² and Rf ¹⁰³ independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms, or an alkyl halide group having 1 to 5 carbon atoms, respectively. Rf ¹⁰² and Rf ¹⁰³ may be the same or different. nf ¹ is an integer of ¹ to 5, and Rf ¹⁰¹ is an organic group containing a fluorine atom. ]

In the formula (f1-1), R is the same as described above. As R, a hydrogen atom or a methyl group is preferable.
In the formula (f1-1), examples of the halogen atom of Rf ¹⁰² and Rf ¹⁰³ include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like, and a fluorine atom is particularly preferable. Examples of the alkyl group having 1 to 5 carbon atoms of Rf ¹⁰² and Rf ¹⁰³ include those similar to the above-mentioned alkyl group having 1 to 5 carbon atoms of R, and a methyl group or an ethyl group is preferable. As the alkyl halide group having 1 to 5 carbon atoms of Rf ¹⁰² and Rf ¹⁰³ , specifically, a group in which a part or all of hydrogen atoms of the alkyl group having 1 to 5 carbon atoms is substituted with a halogen atom is used. Can be mentioned. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like, and a fluorine atom is particularly preferable. Among them, as Rf ¹⁰² and Rf ¹⁰³ , a hydrogen atom, a fluorine atom, or an alkyl group having 1 to 5 carbon atoms is preferable, and a hydrogen atom, a fluorine atom, a methyl group, or an ethyl group is preferable.
In the formula (f1-1), nf ¹ is an integer of ¹ to 5, preferably an integer of 1 to 3, and more preferably 1 or 2.

In the formula (f1-1), Rf ¹⁰¹ is preferably an organic group containing a fluorine atom and preferably a hydrocarbon group containing a fluorine atom.
The hydrocarbon group containing a fluorine atom may be linear, branched or cyclic, and preferably has 1 to 20 carbon atoms, and more preferably 1 to 15 carbon atoms. , 1 to 10 carbon atoms are particularly preferable.
Further, as for the hydrocarbon group containing a fluorine atom, it is preferable that 25% or more of the hydrogen atoms in the hydrocarbon group are fluorinated, more preferably 50% or more is fluorinated, and 60% or more is fluorinated. It is particularly preferable that it is fluorinated because the hydrophobicity of the resist film during immersion exposure is increased.
Among ^these, as ^{Rf 101,} particularly preferably a fluorinated hydrocarbon group having 1 to 6 carbon atoms, a methyl _{group, -CH 2 -CF 3, -CH 2} -CF 2 -CF 3, -CH (CF 3) 2 , -CH _2- CH _2- CF ₃ , -CH _2- CH _2- CF _2- CF _2- CF _2- CF ₃ are most preferable.

The weight average molecular weight (Mw) (polystyrene conversion standard by gel permeation chromatography) of the component (F) is preferably 1000 to 50000, more preferably 5000 to 40,000, and most preferably 1000 to 30000. When it is not more than the upper limit value of this range, it has sufficient solubility in a resist solvent to be used as a resist, and when it is more than the lower limit value of this range, the dry etching resistance and the cross-sectional shape of the resist pattern are good.
The dispersity (Mw / Mn) of the component (F) is preferably 1.0 to 5.0, more preferably 1.0 to 3.0, and most preferably 1.2 to 2.5.

As the component (F), one type may be used alone, or two or more types may be used in combination.
The component (F) is usually used in a ratio of 0.5 to 10 parts by mass with respect to 100 parts by mass of the component (A).

In the present embodiment, the resist composition is further optionally miscible with additives such as additional resins for improving the performance of resist films, dissolution inhibitors, plasticizers, stabilizers, colorants, anti-halation. Agents, dyes and the like can be appropriately added and contained.

(S) component:
In the present embodiment, the resist composition can be produced by dissolving the material in an organic solvent (hereinafter, also referred to as “component (S)”).
The component (S) may be any component as long as it can dissolve each component to be used to form a uniform solution, and any one of those conventionally known as a solvent for chemically amplified resist may be used. Two or more kinds can be appropriately selected and used.
For example, lactones such as γ-butyrolactone; ketones such as acetone, methyl ethyl ketone (MEK), cyclohexanone, methyl-n-pentyl ketone (2-heptanone), methyl isopentyl ketone, etc .; ethylene glycol, diethylene glycol, propylene glycol, di Polyhydric alcohols such as propylene glycol; compounds having an ester bond such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, or dipropylene glycol monoacetate, the polyhydric alcohols or the compound having the ester bond. Derivatives of polyhydric alcohols such as monoalkyl ethers such as monomethyl ethers, monoethyl ethers, monopropyl ethers and monobutyl ethers, or compounds having an ether bond such as monophenyl ethers [among these, propylene glycol monomethyl ether acetate (PGMEA) ), Propylene glycol monomethyl ether (PGME)]; Cyclic ethers such as dioxane, methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methoxy Esters such as methyl propionate, ethyl ethoxypropionate; anisole, ethylbenzyl ether, cresylmethyl ether, diphenyl ether, dibenzyl ether, phenetol, butylphenyl ether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, xylene, Examples thereof include aromatic organic solvents such as simene and mesityrene, and dimethyl sulfoxide (DMSO).
These organic solvents may be used alone or as a mixed solvent of two or more kinds.
Of these, PGMEA, PGME, γ-butyrolactone, and EL are preferable.
Further, a mixed solvent in which PGMEA and a polar solvent are mixed is also preferable. The compounding ratio (mass ratio) may be appropriately determined in consideration of the compatibility between PGMEA and the polar solvent, but is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. It is preferably within the range.
More specifically, when EL or cyclohexanone is blended as the polar solvent, the mass ratio of PGMEA: EL or cyclohexanone is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. .. When PGME is blended as the polar solvent, the mass ratio of PGMEA: PGME is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2, and even more preferably 3: 7 to 7 :. It is 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 mass ratio of the former and the latter is preferably 70:30 to 95: 5 as the mixing ratio.
The amount of the component (S) used is not particularly limited, and is appropriately set according to the coating film thickness at a concentration that can be applied to a substrate or the like. Generally, the resist composition is used so that the solid content concentration is in the range of 1 to 20% by mass, preferably 2 to 15% by mass.

The resist compositions of the present invention include additives that are more miscible as desired, such as additional resins for improving the performance of resist films, dissolution inhibitors, plasticizers, stabilizers, colorants, antihalation agents, etc. Dyes and the like can be appropriately added and contained.

≪Resist pattern formation method≫
The resist pattern forming method according to the second aspect of the present invention is 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 a step of exposing the resist film. It includes a step of developing to form a resist pattern.
The resist pattern forming method of the present invention can be carried out, for example, as follows.
First, the resist composition of the present invention is applied onto a support with a spinner or the like, and a bake (post-apply bake (PAB)) treatment is performed, for example, under a temperature condition of 80 to 150 ° C. for 40 to 120 seconds, preferably 60. Apply for ~ 90 seconds to form a resist film.
Next, the resist film is exposed or masked through a mask (mask pattern) on which a predetermined pattern is formed by using an exposure device such as an ArF exposure device, an electron beam drawing device, or an EUV exposure device. After selective exposure such as drawing by direct irradiation of an electron beam without intervention, baking (post-exposure baking (PEB)) treatment is performed, for example, under a temperature condition of 80 to 150 ° C. for 40 to 120 seconds, preferably 60 to 60 to. Apply for 90 seconds.
Next, the resist film is developed.
In the case of an alkaline developing process, an alkaline developing solution is used, and in the case of a solvent developing process, a developing solution containing an organic solvent (organic developing solution) is used for the developing process.
After the development treatment, a rinsing treatment is preferably performed. In the case of the alkaline development process, the rinsing treatment is preferably a water rinse using pure water, and in the case of the solvent development process, it is preferable to use a rinsing solution containing an organic solvent.
In the case of the solvent development process, after the development treatment or the rinsing treatment, a treatment for removing the developing solution or the rinsing solution adhering to the pattern with a supercritical fluid may be performed.
Drying is performed after the development treatment or the rinsing treatment. In some cases, a baking process (post-baking) may be performed after the development process. In this way, a resist pattern can be obtained.

The support is not particularly limited, and conventionally known ones can be used. For example, a substrate for an electronic component, a substrate on which a predetermined wiring pattern is formed, and the like can be exemplified. More specifically, silicon wafers, metal substrates such as copper, chromium, iron, and aluminum, glass substrates, and the like can be mentioned. As the material of the wiring pattern, for example, copper, aluminum, nickel, gold and the like can be used.
Further, the support may be one in which an inorganic and / or organic film is provided on the substrate as described above. Examples of the inorganic film include an inorganic antireflection film (inorganic BARC). Examples of the organic film include an organic film such as an organic antireflection film (organic BARC) and a lower organic film in a multilayer resist method.
Here, in the multilayer resist method, at least one layer of an organic film (lower layer organic film) and at least one layer of a resist film (upper layer resist film) are provided on a substrate, and a resist pattern formed on the upper layer resist film is used as a mask. It is a method of patterning an lower organic film, and is said to be able to form a pattern having a high aspect ratio. That is, according to the multilayer resist method, since the required thickness can be secured by the lower organic film, the resist film can be thinned and a fine pattern having a high aspect ratio can be formed.
The multilayer resist method basically includes a method of forming a two-layer structure of an upper resist film and a lower organic film (two-layer resist method), and one or more intermediate layers between the upper resist film and the lower organic film. It can be divided into a method of forming a multilayer structure of three or more layers provided with (metal thin film, etc.) (three-layer resist method).

Wavelength used for the exposure is not particularly limited, ArF excimer laser, KrF excimer laser, _{F 2} excimer laser, EUV (extreme ultraviolet), VUV (vacuum ultraviolet), EB (electron beam), X-rays, and soft X-rays It can be done using radiation. The resist composition is highly useful for KrF excimer laser, ArF excimer laser, EB or EUV.

The exposure method of the resist film may be a normal exposure (dry exposure) performed in an inert gas such as air or nitrogen, or an immersion exposure (Liquid Imaging Lithography).
In immersion exposure, the space between the resist film and the lens at the lowest position of the exposure apparatus is previously filled with a solvent (immersion medium) having a refractive index larger than the refractive index of air, and exposure (immersion exposure) is performed in that state. This is an exposure method.
As the immersion medium, a solvent having a refractive index larger than that of air and smaller than that of the resist film to be exposed 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 fluorine-based compounds 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 main components. Examples thereof include liquids, which have a boiling point of 70 to 180 ° C., and more preferably 80 to 160 ° C. It is preferable that the fluorine-based inert liquid has a boiling point in the above range because the medium used for immersion can be removed by a simple method after the end of exposure.
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.
Further, specifically, the perfluoroalkyl ether compound may include perfluoro (2-butyl-tetrahydrofuran) (boiling point 102 ° C.), and the perfluoroalkylamine compound may include perfluorotributylamine (perfluorotributylamine). Boiling point 174 ° C.).
As the immersion medium, water is preferably used from the viewpoints of cost, safety, environmental problems, versatility and the like.

Examples of the alkaline developer used in the developing process in the alkaline developing process include an aqueous solution of 0.1 to 10 mass% tetramethylammonium hydroxide (TMAH).
The organic solvent contained in the organic developer used in the developing process in the solvent developing process may be any known organic solvent as long as it can dissolve the component (A) (component (A) before exposure). It can be selected as appropriate. Specifically, polar solvents such as ketone solvents, ester solvents, alcohol solvents, amide solvents, ether solvents and the like, and hydrocarbon solvents can be used.
A known additive can be added to the organic developer, if necessary. Examples of the additive include a surfactant. The surfactant is not particularly limited, and for example, an ionic or nonionic fluorine-based and / or silicon-based surfactant can be used.
When a surfactant is blended, the blending amount is usually 0.001 to 5% by mass, preferably 0.005 to 2% by mass, and 0.01 to 0.% With respect to the total amount of the organic developer. 5% by mass is more preferable.

The developing process can be carried out by a known developing method. For example, a method of immersing the support in a developing solution for a certain period of time (dip method), or a method in which the developing solution is raised on the surface of the support by surface tension and stopped for a certain period of time. (Paddle method), spraying the developer on the surface of the support (spray method), applying the developer on the support rotating at a constant speed while scanning the developer dispensing nozzle. Examples include a method of continuing (dynamic dispense method).

The rinsing treatment (cleaning treatment) using the rinsing liquid can be carried out by a known rinsing method. Examples of the method include a method of continuously spraying a rinse liquid on a support rotating at a constant speed (rotary coating method), a method of immersing the support in the rinse liquid for a certain period of time (dip method), and a support surface. A method of spraying a rinse solution (spray method) and the like can be mentioned.

The resist composition of the present invention contains the component (B1) as the component (B). Since the component (B1) has high decomposition efficiency of the cation portion, it is presumed that the resist composition of the present invention can form a resist pattern having good lithography characteristics such as sensitivity and a good shape. In addition, the component (B1) has a high effect of suppressing dissolution in the developing solution. Therefore, even when the blending amount of the component (B1) is increased for the purpose of increasing the sensitivity, it is presumed that the film of the formed resist pattern is less likely to be reduced.

≪Compound≫
A third aspect of the present invention is a compound represented by the following general formula (b1).

［式中、Ｗ^ｂは、置換基を有していてもよい炭化水素基である。Ｒ^ｂ１〜Ｒ^ｂ８は、それぞれ独立に、電子吸引性基又は水素原子である。但し、Ｒ^ｂ１〜Ｒ^ｂ８の内の少なくとも１つは電子吸引性基である。Ｒ^ｓ１〜Ｒ^ｓ４は、それぞれ独立に、置換基である。ｎ_ｂ１〜ｎ_ｂ４は、それぞれ独立に、０〜３の整数である。Ｚ^ｎ−は、ｎ価のアニオンであり、ｎは１以上の整数である。］

[In the formula, W ^b is a hydrocarbon group which may have a substituent. R ^{b1 to} R ^b8 are each independently an electron-withdrawing group or a hydrogen atom. However, at least one of R ^{b1 to} R ^b8 is an electron-withdrawing group. R ^{s1 to} R ^s4 are independent substituents. n _{b1 to} n _b4 are independently integers of 0 to 3. Z ⁿ⁻ is an n-valent anion, and n is an integer of 1 or more. ]

The description of the compound of the third aspect of the present invention is the same as the description of the component (B1) described in the resist composition of the first aspect of the present invention.

≪Compound manufacturing method≫
A method for producing the compound (component (B1)) according to the third aspect of the present invention will be described. The method for producing the component (B1) is not particularly limited, and it can be produced by using a known method. For example, the compound (P1) represented by the following formula (P1), the trimethylsilyl trifliolomethanesulfonate, the compound (P2-1) represented by the following formula (P2-1) and / or the following formula (P2-). After the compound (P2-2) represented by 2) is reacted (Grinard reaction) to obtain the compound (P3) represented by the following formula (P3), for example, the compound represented by the following formula (P4) By exchanging salt with (P4), the compound (P5) represented by the following formula (P5) can be obtained as the component (B1).

［式中、Ｗ^ｂ、Ｒ^ｂ１〜Ｒ^ｂ８、Ｒ^ｓ１〜Ｒ^ｓ４、ｎ_ｂ１〜ｎ_ｂ４は、前記と同様である。Ｚ⁻は、１価のアニオンであり、Ｘはハロゲン原子である。］

[In the formula, W ^b , R ^{b1 to} R ^b8 , R ^{s1 to} R ^s4 , and n _{b1 to} n _b4 are the same as described above. Z ⁻ is a monovalent anion and X is a halogen atom. ]

As the compound (P1), the compound (P2-1) and the compound (P2-2), commercially available ones may be used, or those synthesized by a known production method may be used.
The solvent used may be any solvent as long as the above compound (P1), the above compound (P2-1) and the above compound (P2-2) are soluble and do not react with them. For example, dichloromethane, dichloroethane, chloroform, etc. Examples thereof include tetrahydrofuran, N, N-dimethylformamide, acetonitrile, propionitrile and the like.

After completion of the reaction, the compound in the reaction solution may be isolated and purified. Conventionally known methods can be used for isolation and purification. For example, concentration, solvent extraction, distillation, crystallization, recrystallization, chromatography and the like can be used alone or in combination of two or more thereof.

The structures of the compounds obtained as described above are: 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, elemental analysis method, X-ray crystal diffraction method and other general organic analysis methods.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples.

<Manufacturing of compounds>
(Example 1)
[Synthesis of compound P-2]
To a three-necked flask equipped with a reflux tube and a thermometer, 0.64 g (26.4 mmol) of magnesium and 19.4 g of tetrahydrofuran (THF) were added, and the mixture was heated to 40 ° C. with stirring. To this, 4.85 g (24.0 mmol) of 3-trifluoromethyl-1-bromobenzene was slowly added dropwise so that the reaction solution temperature did not exceed 50 ° C. After completion of the dropping, stirring was continued for 1 hour to obtain compound P-2.

[Synthesis of compound PAG-1]
3.26 g (10.0 mmol) of compound P-1 and 13.1 g of THF were added to a three-necked flask equipped with a three-way cock and a thermometer, and the mixture was cooled to −20 ° C. with stirring. To this, 6.67 g (30.0 mmol) of trimethylsilyl trifuriolomethanesulfonate was added, and the mixture was aged for 30 minutes. Compound P-2 was slowly added dropwise thereto so that the temperature of the reaction solution did not exceed 0 ° C., and the mixture was aged for 3 hours.
After aging, 32.6 g of pure water was slowly added dropwise so that the temperature of the reaction solution did not exceed 0 ° C., the temperature was raised to room temperature, the aqueous phase was removed, and the mixture was further washed 4 times with 16.3 g of pure water. ..
Next, 4.16 g of compound P-4 and 32.6 g of pure water were added to the organic phase and stirred to extract the organic phase. This organic phase was washed 6 times with 32.6 g of pure water, and then added dropwise to a large amount of t-butyl methyl ether to precipitate. The precipitate (powder) was separated by filtration and dried to obtain 6.77 g of compound PAG-1.

The obtained compound PAG-1 was subjected to NMR analysis and confirmed to be the target compound. The results of the NMR analysis are shown below.
^{1 1} H-NMR (DMSO-d ₆ , 400 MHz) δ 1.64-1.96 (m, 30H), 4.55 (t, 4H), 7.76-8.12 (m, 20H), 8. 24 (s, 2H)
¹⁹ F-NMR (DMSO-d ₆ , 400 MHz) δ-59.1 (s, 6F), -112.2 (s, 4F)

(Example 2)
Compound PAG-2 was obtained in the same manner as in Example 1 except that compound P-4 was changed to a compound having a corresponding anion (sodium salt).

The obtained compound PAG-2 was subjected to NMR analysis and confirmed to be the target compound. The results of the NMR analysis are shown below.
^{1 1} H-NMR (DMSO-d ₆ , 400 MHz) δ 1.73-2.21 (m, 8H), 2.47-2.49 (m, 2H), 3.88 (t, 2H), 4. 46 (t, 2H), 4.78 (m, 2H), 7.76-8.12 (m, 20H), 8.24 (s, 2H)
¹⁹ F-NMR (DMSO-d ₆ , 400 MHz) δ-59.1 (s, 6F), -112.2 (s, 4F)

(Example 3)
Compound PAG-3 was obtained in the same manner as in Example 1 except that compound P-4 was changed to a compound having a corresponding anion (sodium salt).

The obtained compound PAG-3 was subjected to NMR analysis and confirmed to be the target compound. The results of the NMR analysis are shown below.
^{1 1} H-NMR (DMSO-d ₆ , 400 MHz) δ 7.76-8.12 (m, 20H), 8.24 (s, 2H)
¹⁹ F-NMR (DMSO-d ₆ , 400 MHz) δ-59.1 (s, 6F), -77.3 (s, 6F), -111.5 (s, 4F), -118.1 (s,, 4F), -122.4 (s, 4F)

(Example 4)
Compound PAG-4 was obtained in the same manner as in Example 1 except that compound P-4 was changed to a compound having a corresponding anion (sodium salt).

The obtained compound PAG-4 was subjected to NMR analysis and confirmed to be the target compound. The results of the NMR analysis are shown below.
^{1 1} H-NMR (DMSO-d ₆ , 400 MHz) δ 0.75 (d, 6H), 1.13-1.40 (m, 14H), 1.49 (dt, 2H), 1.62-2. 47 (m, 36H), 2.83 (t, 2H),
2.92-3.10 (m, 4H), 4.06-4.23 (m, 4H), 4.87-5.11 (m, 2H), 7.76-8.12 (m, 20H) ), 8.24 (s, 2H)
¹⁹ F-NMR (DMSO-d ₆ , 400 MHz) δ-59.1 (s, 6F), -108.6 (d, 2F), -116.5 (d, 2F), -204.2 (s, 2F)

(Example 5)
Compound PAG-5 was obtained in the same manner as in Example 1 except that compound P-4 was changed to a compound having a corresponding anion (sodium salt).

The obtained compound PAG-5 was subjected to NMR analysis and confirmed to be the target compound. The results of the NMR analysis are shown below.
^{1 1} H-NMR (DMSO-d ₆ , 400 MHz) δ 1.64-1.96 (m, 30H), 4.55 (t, 4H),
7.73-7.92 (m, 10H), 7.95 (s, 2H), 8.03-8.19 (m, 10H)
¹⁹ F-NMR (DMSO-d ₆ , 400 MHz) δ-107.7 (s, 2F), -112.2 (s, 4F)

(Example 6)
Compound PAG-6 was obtained in the same manner as in Example 1 except that compound P-4 was changed to a compound having a corresponding anion (sodium salt).

The obtained compound PAG-6 was subjected to NMR analysis and confirmed to be the target compound. The results of the NMR analysis are shown below.
^{1 1} H-NMR (DMSO-d ₆ , 400 MHz) δ 1.64-1.96 (m, 30H), 4.55 (t, 4H), 7.92 (s, 4H), 8.00-8. 18 (m, 16H)
¹⁹ F-NMR (DMSO-d ₆ , 400 MHz) δ-107.7 (s, 4F), -112.2 (s, 4F)

(Example 7)
Compound PAG-7 was obtained in the same manner as in Example 1 except that compound P-4 was changed to a compound having a corresponding anion (sodium salt).

The obtained compound PAG-7 was subjected to NMR analysis and confirmed to be the target compound. The results of the NMR analysis are shown below.
^{1 1} H-NMR (DMSO-d ₆ , 400 MHz) δ 1.64-1.96 (m, 30H), 4.55 (t, 4H), 7.89 (s, 4H), 8.01 (s,, 4H), 8.07 (s, 8H)
¹⁹ F-NMR (DMSO-d ₆ , 400 MHz) δ-105.7 (s, 8F), -112.2 (s, 4F)

<Preparation of resist composition>
(Examples 8 to 21, Comparative Examples 1 to 12)
Each component shown in Tables 1 and 2 was mixed and dissolved to prepare a resist composition.

Each abbreviation in Tables 1 and 2 has the following meanings. The value in [] is the blending amount (part by mass).
(A) -1: A polymer represented by the following chemical formula (A) -1. The weight average molecular weight (Mw) in terms of standard polystyrene determined by GPC measurement is 7600, and the molecular weight dispersion (Mw / Mn) is 1.92. ^{13 The} copolymerization composition ratio (ratio of each structural unit in the structural formula (molar ratio)) determined by C-NMR is l / m / n = 45/30/25.
(A) -2: A polymer represented by the following chemical formula (A) -2. The weight average molecular weight (Mw) in terms of standard polystyrene determined by GPC measurement is 9000, and the molecular weight dispersion (Mw / Mn) is 1.94. ^{13 The} copolymerization composition ratio (ratio of each structural unit in the structural formula (molar ratio)) determined by C-NMR is l / m / n = 45/30/25.
(A) -3: A polymer represented by the following chemical formula (A) -3. The weight average molecular weight (Mw) in terms of standard polystyrene determined by GPC measurement is 6800, and the molecular weight dispersion (Mw / Mn) is 1.64. ^{13 The} copolymerization composition ratio (ratio of each structural unit in the structural formula (molar ratio)) determined by C-NMR is l / m = 60/40.
(A) -4: A polymer represented by the following chemical formula (A) -4. The weight average molecular weight (Mw) in terms of standard polystyrene determined by GPC measurement is 5500, and the molecular weight dispersion (Mw / Mn) is 1.54. ^{13 The} copolymerization composition ratio (ratio of each structural unit in the structural formula (molar ratio)) determined by C-NMR is l / m = 60/40.

(B) -1 to (B) -7: The above-mentioned compound PAG-1 to compound PAG-7.
(B) -8 to (B) -13: Compounds represented by the following chemical formulas (B) -8 to (B) -13, respectively.

(D) -1: A compound represented by the following chemical formula (D) -1.
(S) -1: Mixed solvent of propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether = 20/80 (mass ratio).

<Formation of resist pattern>
The resist composition of each example was applied onto an 8-inch silicon substrate treated with hexamethyldisilazane (HMDS) using a spinner, and prebaked on a hot plate at a temperature of 110 ° C. for 60 seconds. The PAB) treatment was performed and dried to form a resist film having a film thickness of 30 nm.
Next, for the resist film, an electron beam drawing device JEOL-JBX-9300FS (manufactured by JEOL Ltd.) was used, and the target size was set to a 1: 1 line-and-space pattern with a line width of 50 to 16 nm at an acceleration voltage of 100 kV. (Hereinafter referred to as "LS pattern"), drawing (exposure) was performed.
After drawing, heat treatment (PEB) was performed after drawing on a hot plate at a temperature of 110 ° C. for 60 seconds, and then at 23 ° C., a 2.38 mass% tetramethylammonium hydroxide (TMAH) aqueous solution "NMD". -3 ”(trade name, manufactured by Tokyo Ohka Kogyo Co., Ltd.) was used for 60 seconds of alkaline development. Then, water rinse was performed for 60 seconds using pure water.
As a result, a 1: 1 LS pattern with a line width of 50 to 16 nm was formed.

[Evaluation of Optimal Exposure (Eop)]
The optimum exposure amount Eop (μC / cm ² ) at which the target size LS pattern is formed was determined by the above <resist pattern formation>. The results are shown in Tables 3 to 4 as "Eop (μC / cm ² )".

[Evaluation of resolution]
Scanning electron microscope with respect to the limit resolution in the above Eop, specifically, the minimum dimension of the pattern that resolves without collapsing when the exposure amount is gradually increased from the optimum exposure amount Eop to form an LS pattern. It was obtained using S-9380 (manufactured by Hitachi High-Technologies Corporation). The results are shown in Tables 3 to 4 as "resolution (nm)".

[Evaluation of LWR (Linewise Roughness)]
For the LS pattern formed in the above <Formation of resist pattern>, 3σ, which is a scale indicating LWR, was determined.
"3σ" is obtained by measuring 400 line positions in the longitudinal direction of the line using a scanning electron microscope (acceleration voltage 800V, trade name: S-9380, manufactured by Hitachi High-Technologies Corporation) and obtaining from the measurement results. It shows a triple value (3σ) (unit: nm) of the standard deviation (σ).
The smaller the value of 3σ, the smaller the roughness of the side wall of the line, which means that an LS pattern having a more uniform width was formed. The results are shown in Tables 3 to 4 as "LWR (nm)".

[Evaluation of resist pattern shape]
The cross-sectional shape of the LS pattern formed in the above <Formation of resist pattern> was observed by a length measuring SEM (scanning electron microscope, accelerating voltage 800V, trade name: SU-8000, manufactured by Hitachi High-Technologies Corporation). The results are shown in Tables 3 to 4 as "shapes".

As shown in the above results, the resist patterns formed using the resist compositions of Examples 8 to 21 have higher resolution and LWR than the resist patterns formed using the resist compositions of Comparative Examples 1 to 12. It was confirmed that the lithography characteristics such as the above were better and the shape was good.

Claims (13)

A resist composition that generates an acid upon exposure and changes its solubility in a developing solution by the action of the acid.
Contains an acid generator component (B) that generates acid upon exposure
The resist composition, wherein the acid generator component (B) contains a compound (B1) represented by the following general formula (b1).

[In the formula, W ^b is a hydrocarbon group which may have a substituent. R ^{b1 to} R ^b8 are each independently an electron-withdrawing group or a hydrogen atom. ^However, the R ^b1 of the R b1 ^{to R b8,} and ^{R b5} or ^{R b6,} but at least electron-withdrawing group. R ^{s1 to} R ^s4 are independent substituents. n _{b1 to} n _b4 are independently integers of 0 to 3. Z ⁿ⁻ is an n-valent anion, and n is an integer of 1 or more. ] The resist composition according to claim 1, wherein the compound (B1) is an aromatic hydrocarbon group in which W ^b in the formula (b1) may have a substituent. In the compound (B1), Z ^{n− in the} formula (b1) is an anion represented by the following general formula (b1-a1), an anion represented by the general formula (b1-a2), or a general formula (b1-a2). The resist composition according to claim 1 or 2 , which is an anion represented by b1-a3).

[In the formula, R ¹⁰¹ and R ^{104 to} R ¹⁰⁸ each independently have a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a substituent. It is a chain alkenyl group that may have. R ¹⁰⁴ and R ¹⁰⁵ may be coupled to each other to form a ring. R ¹⁰² is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. Y ¹⁰¹ is a divalent linking group or a single bond containing an oxygen atom. V ^{101 to} V ¹⁰³ are each independently a single bond, an alkylene group or a fluorinated alkylene group. L ^{101 to} L ¹⁰² are each independently a single bond or an oxygen atom. L ^{103 to} L ¹⁰⁵ are each independently single-bonded, -CO- or -SO _2- . ] The resist composition according to any one of claims 1 to 3 , further comprising a base material component (A) whose solubility in a developing solution is changed by the action of an acid. The resist composition according to claim 4 , wherein the content of the compound (B1) is 5 to 45 parts by mass with respect to 100 parts by mass of the base material component (A). The resist composition according to claim 4 or 5 , wherein the base material component (A) contains a polymer compound (A1) having a structural unit containing an acid-degradable group whose polarity is increased by the action of an acid. The resist composition according to claim 6 , wherein the polymer compound (A1) further has a structural unit containing a hydroxystyrene skeleton. The resist composition according to claim 6 or 7 , wherein the polymer compound (A1) further has a structural unit containing a lactone-containing cyclic group, a -SO ₂ -containing cyclic group, or a carbonate-containing cyclic group. The resist composition according to claim 7 or 8 , wherein the polymer compound (A1) further has a structural unit represented by the following general formula (a9-1).

[In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or an alkyl halide group having 1 to 5 carbon atoms. Ya ⁹¹ is a single bond or divalent linking group. Ya ⁹² is a divalent linking group. R ⁹¹ is a hydrocarbon group which may have a substituent. ] A step of forming a resist film using the resist composition according to any one of claims 1 to 9 on a support, a step of exposing the resist film, and a step of developing the resist film after the exposure. A resist pattern forming method including a step of forming a resist pattern. A compound represented by the following general formula (b1).

[In the formula, W ^b is a hydrocarbon group which may have a substituent. R ^{b1 to} R ^b8 are each independently an electron-withdrawing group or a hydrogen atom. ^However, the R ^b1 of the R b1 ^{to R b8,} and ^{R b5} or ^{R b6,} but at least electron-withdrawing group. R ^{s1 to} R ^s4 are independent substituents. n _{b1 to} n _b4 are independently integers of 0 to 3. Z ⁿ⁻ is an n-valent anion, and n is an integer of 1 or more. ] The compound according to claim 11 , wherein W ^b in the formula (b1) is an aromatic hydrocarbon group which may have a substituent. Z ^{n− in the} formula (b1) is represented by the anion represented by the following general formula (b1-a1), the anion represented by the general formula (b1-a2), or the general formula (b1-a3). The compound according to claim 11 or 12 , which is an anion.

[In the formula, R ¹⁰¹ and R ^{104 to} R ¹⁰⁸ each independently have a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a substituent. It is a chain alkenyl group that may have. R ¹⁰⁴ and R ¹⁰⁵ may be coupled to each other to form a ring. R ¹⁰² is a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. Y ¹⁰¹ is a divalent linking group or a single bond containing an oxygen atom. V ^{101 to} V ¹⁰³ are each independently a single bond, an alkylene group or a fluorinated alkylene group. L ^{101 to} L ¹⁰² are each independently a single bond or an oxygen atom. L ^{103 to} L ¹⁰⁵ are each independently single-bonded, -CO- or -SO _2- . ]