JP2012168497A - Resist composition and resist pattern manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resist composition which can manufacture a resist pattern with excellent focus margin (DOF).SOLUTION: A resist composition contains a resin having a structural unit represented by formula (a), an acid generator represented by formula (B1), and a solvent, where Rrepresents an aliphatic hydrocarbon group or the like which may have a substituent; Rrepresents a sulpholane ring group represented by formula (b); R represents a hydroxy group, an alkoxy group or an aliphatic hydrocarbon group; and * represents a direct bond to R.

Description

  The present invention relates to a resist composition, a method for producing a resist pattern, and the like.

  In recent years, an optical lithography technique using a short wavelength light such as an ArF excimer laser (wavelength: 193 nm) as an exposure source has been actively studied as a semiconductor microfabrication technique. The resist composition used in such a photolithography technique includes a resin whose solubility in an alkaline aqueous solution is changed by the action of an acid, an acid generator, and a solvent.

For example, Patent Document 1 discloses a resin composed of a structural unit represented by the formula (u-A), a structural unit represented by the formula (u-B), and a structural unit represented by the formula (u-C). And a resist composition containing an acid generator represented by the formula (B2) and a solvent.

JP 2007-161707 A

  In the production of resist patterns using lithography technology, it has been demanded that resist patterns can be produced with a wider focus margin as the design dimensions become finer. In terms of producing a resist pattern with a wider focus margin, the resist composition containing the salt described in Patent Document 1 as an acid generator has room for improvement.

［式（ａ）中、
Ｒ^１は、ハロゲン原子を有してもよい炭素数１〜６のアルキル基、水素原子又はハロゲン原子を表す。
Ｒ^２は、置換基を有していてもよい炭素数１〜６の脂肪族炭化水素基、単結合又は式（ａ−１）で表される基を表す。

（式（ａ−１）中、
ｓは０又は１を表す。
Ａ¹⁰及びＡ^1１は、それぞれ独立に、置換基を有していてもよい炭素数１〜５の脂肪族炭化水素基を表す。
Ａ^1２は、置換基を有していてもよい炭素数１〜５の脂肪族炭化水素基又は単結合を表す。
Ｘ¹⁰及びＸ¹¹は、それぞれ独立に、酸素原子、カルボニル基、カルボニルオキシ基又はオキシカルボニル基を表す。）
Ｒ^３は、式（ｂ）で表されるスルホラン環基を表す。

（式（ｂ）中、
ｎは０〜７の整数を表す。
Ｒは、ヒドロキシ基、アルコキシ基又は炭素数１〜１８の脂肪族炭化水素基を表し、ｎが２以上の場合、複数のＲは同一でも異なっていてもよく、隣接する炭素原子に各々結合する２つのＲが結合して、前記炭素原子とともに環を形成してもよい。
---は、単結合又は二重結合を表す。
＊は、Ｒ^２との結合手である。）］
（Ｂ）式（Ｂ１）で表される酸発生剤

［式（Ｂ１）中、
Ｑ¹及びＱ²は、それぞれ独立に、フッ素原子又は炭素数１〜６のペルフルオロアルキル基を表す。
Ｌ^b1は、２価の炭素数１〜１７の飽和炭化水素基を表し、該飽和炭化水素基を構成するメチレン基は、酸素原子又はカルボニル基で置き換わっていてもよい。
Ｙは、置換基を有していてもよい炭素数１〜１８の脂肪族炭化水素基を表し、該脂肪族炭化水素基を構成するメチレン基は、酸素原子、スルホニル基又はカルボニル基に置き換わっていてもよい。
Ｚ⁺は、有機カチオンを表す。］
（Ｄ）溶剤 In view of the above circumstances, the present inventors have intensively studied to arrive at the present invention. That is, the present invention includes the following inventions.
[1] A resist composition containing the following (A), (B) and (D).
(A) Resin having a structural unit represented by formula (a)

[In the formula (a),
R ¹ represents a C 1-6 alkyl group, a hydrogen atom or a halogen atom which may have a halogen atom.
R ² represents an optionally substituted aliphatic hydrocarbon group having 1 to 6 carbon atoms, a single bond, or a group represented by the formula (a-1).

(In the formula (a-1),
s represents 0 or 1.
A ¹⁰ and A ¹¹ each independently represent a C 1-5 aliphatic hydrocarbon group which may have a substituent.
A ¹² represents an aliphatic hydrocarbon group having 1 to 5 carbon atoms which may have a substituent or a single bond.
X ¹⁰ and X ¹¹ each independently represent an oxygen atom, a carbonyl group, a carbonyloxy group or an oxycarbonyl group. )
R ³ represents a sulfolane ring group represented by the formula (b).

(In the formula (b),
n represents an integer of 0 to 7.
R represents a hydroxy group, an alkoxy group, or an aliphatic hydrocarbon group having 1 to 18 carbon atoms, and when n is 2 or more, a plurality of R may be the same or different and are each bonded to adjacent carbon atoms. Two Rs may combine to form a ring together with the carbon atom.
--- represents a single bond or a double bond.
* Is a bond with R ² . ]]
(B) Acid generator represented by formula (B1)

[In the formula (B1),
Q ¹ and Q ² each independently represents a fluorine atom or a C 1-6 perfluoroalkyl group.
L ^b1 represents a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, and the methylene group constituting the saturated hydrocarbon group may be replaced with an oxygen atom or a carbonyl group.
Y represents an optionally substituted aliphatic hydrocarbon group having 1 to 18 carbon atoms, and the methylene group constituting the aliphatic hydrocarbon group is replaced with an oxygen atom, a sulfonyl group or a carbonyl group. May be.
Z ⁺ represents an organic cation. ]
(D) Solvent

［式（ｂ−１）〜式（ｂ−５）中、＊は、Ｒ^２との結合手を表す。］ [2] (A)
R ^{2 in the} formula (a) is a single bond, —CH ₂ —CO—O— * or —CH ₂ —CH ₂ —O—CO— * (* is a bond to R ³ ). [1] The resist composition according to [1], which is a resin.
[3] (A)
The resist composition according to [1] or [2], wherein R ^{3 in the} formula (a) is a resin having a sulfolane ring group selected from the group consisting of the formulas (b-1) to (b-5).

[In formula (b-1) to formula (b-5), * represents a bond to R ² . ]

［式（ａ１−１）及び式（ａ１−２）中、
Ｌ^a1及びＬ^a2は、それぞれ独立に、酸素原子又は^＊−Ｏ−（ＣＨ₂）_k1−ＣＯ−Ｏ−（ｋ１は１〜７の整数を表し、＊は−ＣＯ−との結合手を表す。）を表われる基である。
Ｒ^a4及びＲ^a5は、それぞれ独立に、水素原子又はメチル基を表す。
Ｒ^a6及びＲ^a7は、それぞれ独立に、炭素数１〜８のアルキル基又は炭素数３〜１０の脂環式炭化水素基を表す。
ｍ１は０〜１４の整数を表す。
ｎ１は０〜１０の整数を表す。
ｎ２は０〜３の整数を表す。］ [4] The resist composition according to any one of [1] to [3], wherein (A) is a resin that is insoluble or hardly soluble in an alkaline aqueous solution and can be dissolved in an alkaline aqueous solution by the action of an acid.
[5] (A)
The resist composition according to claim 4, which is a resin having a structural unit represented by formula (a1-1) or formula (a1-2).

[In Formula (a1-1) and Formula (a1-2),
L ^a1 and L ^a2 each independently represent an oxygen atom or ^* —O— (CH ₂ ) _k1 —CO—O— (k1 represents an integer of 1 to 7, and * represents a bond to —CO—. .).
R ^a4 and R ^a5 each independently represent a hydrogen atom or a methyl group.
R ^a6 and R ^a7 each independently represent an alkyl group having 1 to 8 carbon atoms or an alicyclic hydrocarbon group having 3 to 10 carbon atoms.
m1 represents the integer of 0-14.
n1 represents an integer of 0 to 10.
n2 represents an integer of 0 to 3. ]

  [6] The resist composition according to any one of [1] to [5], further containing a basic compound.

[7] (1) A step of applying the resist composition according to any one of [1] to [6] on a substrate,
(2) a step of removing the solvent from the composition after coating to form a composition layer;
(3) a step of exposing the composition layer,
(4) A step of heating the composition layer after exposure,
(5) a step of developing the composition layer after heating;
A method for producing a resist pattern including:

［式（ａｍ’）中、
Ｒ^１は、ハロゲン原子を有してもよい炭素数１〜６のアルキル基、水素原子又はハロゲン原子を表す。
Ｒ^2xは、置換基を有していてもよい炭素数１〜６の脂肪族炭化水素基又は式（ａ−１）で表される基を表す。

（式（ａ−１）中、
ｓは０又は１を表す。
Ａ¹⁰及びＡ^1１は、それぞれ独立に、置換基を有していてもよい炭素数１〜５の脂肪族炭化水素基を表す。
Ａ^1２は、置換基を有していてもよい炭素数１〜５の脂肪族炭化水素基又は単結合を表す。
Ｘ¹⁰及びＸ¹¹は、それぞれ独立に、酸素原子、カルボニル基、カルボニルオキシ基又はオキシカルボニル基を表す。）
Ｒ^３は、式（ｂ）で表されるスルホラン環基を表す。

（式（ｂ）中、
ｎは０〜７の整数を表す。
Ｒは、ヒドロキシ基、アルコキシ基又は炭素数１〜１８の脂肪族炭化水素基を表し、ｎが２以上の場合、複数のＲは同一でも異なっていてもよく、隣接する炭素原子に各々結合する２つのＲが結合して、前記炭素原子とともに環を形成してもよい。
---は、単結合又は二重結合を表す。
＊は、Ｒ^２との結合手である。）］
〔９〕前記〔８〕記載の化合物に由来する構造単位を有する樹脂。 [8] A compound represented by the formula (am ′).

[In the formula (am ′),
R ¹ represents a C 1-6 alkyl group, a hydrogen atom or a halogen atom which may have a halogen atom.
R ^2x represents a C 1-6 aliphatic hydrocarbon group which may have a substituent or a group represented by the formula (a-1).

(In the formula (a-1),
s represents 0 or 1.
A ¹⁰ and A ¹¹ each independently represent a C 1-5 aliphatic hydrocarbon group which may have a substituent.
A ¹² represents an aliphatic hydrocarbon group having 1 to 5 carbon atoms which may have a substituent or a single bond.
X ¹⁰ and X ¹¹ each independently represent an oxygen atom, a carbonyl group, a carbonyloxy group or an oxycarbonyl group. )
R ³ represents a sulfolane ring group represented by the formula (b).

(In the formula (b),
n represents an integer of 0 to 7.
R represents a hydroxy group, an alkoxy group, or an aliphatic hydrocarbon group having 1 to 18 carbon atoms, and when n is 2 or more, a plurality of R may be the same or different and are each bonded to adjacent carbon atoms. Two Rs may combine to form a ring together with the carbon atom.
--- represents a single bond or a double bond.
* Is a bond with R ² . ]]
[9] A resin having a structural unit derived from the compound of [8].

  According to the resist composition of the present invention, a resist pattern can be produced with an excellent focus margin (DOF).

  In the present specification, unless otherwise specified, the following examples of substituents are applied to any chemical structural formula having the same substituents while appropriately selecting the number of carbon atoms.

The hydrocarbon group includes an aliphatic hydrocarbon group and an aromatic hydrocarbon group.
Aliphatic hydrocarbon groups include both linear (linear and branched) and cyclic, and unless otherwise defined, also include combinations of linear and cyclic aliphatic hydrocarbon groups. . Moreover, these aliphatic hydrocarbon groups may contain a carbon-carbon double bond in a part thereof, but a saturated group (aliphatic saturated hydrocarbon group) is preferable. When stereoisomers exist, all stereoisomers are included.
Of the chain aliphatic hydrocarbon groups, the monovalent one typically includes an alkyl group.
Examples of the alkyl group include a methyl group (C ₁ ), an ethyl group (C ₂ ), a propyl group (C ₃ ), a butyl group (C ₄ ), a pentyl group (C ₅ ), a hexyl group (C ₆ ), a heptyl group ( C ₇ ), octyl group (C ₈ ), decyl group (C ₁₀ ), dodecyl group (C ₁₂ ), hexadecyl group (C ₁₄ ), pentadecyl group (C ₁₅ ), hexyldecyl group (C ₁₆ ), heptadecyl group ( C ₁₇ ) and octadecyl group (C ₁₈ ).
Examples of the divalent group of chain aliphatic hydrocarbon groups include alkanediyl groups in which one hydrogen atom has been removed from an alkyl group.
Examples of alkanediyl groups include methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane-1,5-diyl group, hexane- 1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, nonane-1,9-diyl group, decane-1,10-diyl group, undecane-1,11-diyl Group, dodecane-1,12-diyl group, tridecane-1,13-diyl group, tetradecane-1,14-diyl group, pentadecane-1,15-diyl group, hexadecane-1,16-diyl group, heptadecane-1 , 17-diyl group, methylidene group, ethylidene group, propylidene group, 2-propylidene group, 1-methyl-1,3-propylene group, 2-methyl-1,3-propylene group, 2-methyl group Le-1,2-propylene group, and 1-methyl-1,4-butylene group and 2-methyl-1,4-butylene group.

  The cyclic aliphatic hydrocarbon group (hereinafter sometimes referred to as “alicyclic hydrocarbon group”) typically means a cycloalkyl group, and includes any of the monocyclic and polycyclic groups shown below. Is also included.

As a monovalent alicyclic hydrocarbon group, a monocyclic aliphatic hydrocarbon group represents 1 hydrogen atom of a cycloalkane represented by the following formulas (KA-1) to (KA-7). It is a group that has been removed.

The polycyclic aliphatic hydrocarbon group is a group in which one hydrogen atom of a cycloalkane represented by the following formulas (KA-8) to (KA-19) is removed.

  Examples of the divalent alicyclic hydrocarbon group include groups in which two hydrogen atoms have been removed from the alicyclic hydrocarbon of formula (KA-1) to formula (KA-19).

The aliphatic hydrocarbon group may have a substituent. As such a substituent, a halogen atom, a hydroxy group, an alkoxy group, an alkylthio group, an acyl group, an acyloxy group, an aryl group, an aralkyl group, and an aryloxy group may be mentioned unless otherwise limited.
Here, as a halogen atom, a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom are mentioned.
Examples of alkoxy groups include methoxy group (C ₁ ), ethoxy group (C ₂ ), propoxy group (C ₃ ), butoxy group (C ₄ ), pentyloxy group (C ₅ ), hexyloxy group (C ₆ ), heptyl Examples thereof include an oxy group (C ₇ ), an octyloxy group (C ₈ ), a decyloxy group (C ₁₀ ), and a dodecyloxy group (C ₁₂ ).
Examples of the alkylthio group include those in which an oxygen atom of an alkoxy group is replaced by a sulfur atom, such as a methylthio group, an ethylthio group, a propylthio group, a butylthio group, a pentylthio group, a hexylthio group, a heptylthio group, an octylthio group, a decylthio group, and the like. Examples include dodecylthio group.
As the acyl group, acetyl group (C ₂ ), propionyl group (C ₃ ), butyryl group (C ₄ ), valeryl group (C ₅ ), hexylcarbonyl group (C ₆ ), heptylcarbonyl group (C ₇ ), octyl An alkyl group such as a carbonyl group (C ₈ ), a decylcarbonyl group (C ₁₀ ) and a dodecylcarbonyl group (C ₁₂ ) and a carbonyl group, and an aryl group such as a benzoyl group (C ₇ ) and a carbonyl group Combined are included.
Examples of the acyloxy group include an acetyloxy group, a propionyloxy group, a butyryloxy group, and an isobutyryloxy group.
Examples of the aralkyl group include benzyl group (C ₇ ), phenethyl group (C ₈ ), phenylpropyl group (C ₉ ), naphthylmethyl group (C ₁₁ ), and naphthylethyl group (C ₁₂ ).
The aryloxy group includes phenyloxy group (C ₆ ), naphthyloxy group (C ₁₀ ), antonyloxy group (C ₁₄ ), biphenyloxy group (C ₁₂ ), phenanthryloxy group (C ₁₄ ) and full A combination of an aryl group such as an oleenyloxy group (C ₁₃ ) and an oxygen atom is exemplified.

The monovalent aromatic hydrocarbon group typically includes an aryl group.
Examples of the aryl group include a phenyl group (C ₆ ), a naphthyl group (C ₁₀ ), an antonyl group (C ₁₄ ), a biphenyl group (C ₁₂ ), a phenanthryl group (C ₁₄ ), and a fluorenyl group (C ₁₃ ). .
The aromatic hydrocarbon group may have a substituent. Unless such a substituent is particularly limited, a halogen atom, a hydroxy group, an alkoxy group, an acyl group, an acyloxy group, an alkyl group, and an aryloxy group are exemplified.

Further, "(meth) acrylic monomer" means at least one monomer having a structure of "CH ₂ = CH-CO-" or _{"CH 2 = C (CH 3)} -CO- ". Similarly, “(meth) acrylate” and “(meth) acrylic acid” mean “at least one of acrylate and methacrylate” and “at least one of acrylic acid and methacrylic acid”, respectively.

  Hereinafter, (A) a resin having a structural unit represented by the above formula (a), which is a constituent component of the resist composition of the present invention (hereinafter sometimes referred to as “the present resist composition”) (hereinafter referred to as “ Resin (A) "), (B) an acid generator represented by the formula (B1) (hereinafter sometimes referred to as" acid generator (B) "), and a basic compound (optionally contained) Hereinafter, each of the “basic compound (C)” and the (D) solvent (hereinafter, sometimes referred to as “solvent (D)”) will be described.

［式（ａ）中、
Ｒ^１は、ハロゲン原子を有してもよい炭素数１〜６のアルキル基、水素原子又はハロゲン原子を表す。
Ｒ^２は、置換基を有していてもよい炭素数１〜６の脂肪族炭化水素基、単結合又は式（ａ−１）で表される基を表す。

（式（ａ−１）中、
ｓは０又は１を表す。
Ａ¹⁰及びＡ^1１は、それぞれ独立に、置換基を有していてもよい炭素数１〜５の脂肪族炭化水素基を表す。
Ａ^1２は、置換基を有していてもよい炭素数１〜５の脂肪族炭化水素基又は単結合を表す。
Ｘ¹⁰及びＸ¹¹は、それぞれ独立に、酸素原子、カルボニル基、カルボニルオキシ基又はオキシカルボニル基を表す。）
Ｒ^３は、式（ｂ）で表されるスルホラン環基を表す。

（式（ｂ）中、
ｎは０〜７の整数を表す。
Ｒは、ヒドロキシ基、アルコキシ基又は炭素数１〜１８の脂肪族炭化水素基を表し、ｎが２以上の場合、複数のＲは同一でも異なっていてもよく、隣接する炭素原子に各々結合する２つのＲが結合して、前記炭素原子とともに環を形成してもよい。
---は、単結合又は二重結合を表す。
＊は、Ｒ^２との結合手である。）］
なお、前記式（ａ−１）で表される基を場合により、「基（ａ−１）」という。 <Resin (A)>
The resin (A) has a structural unit represented by the formula (a) (hereinafter sometimes referred to as “structural unit (a)”).

[In the formula (a),
R ¹ represents a C 1-6 alkyl group, a hydrogen atom or a halogen atom which may have a halogen atom.
R ² represents an optionally substituted aliphatic hydrocarbon group having 1 to 6 carbon atoms, a single bond, or a group represented by the formula (a-1).

(In the formula (a-1),
s represents 0 or 1.
A ¹⁰ and A ¹¹ each independently represent a C 1-5 aliphatic hydrocarbon group which may have a substituent.
A ¹² represents an aliphatic hydrocarbon group having 1 to 5 carbon atoms which may have a substituent or a single bond.
X ¹⁰ and X ¹¹ each independently represent an oxygen atom, a carbonyl group, a carbonyloxy group or an oxycarbonyl group. )
R ³ represents a sulfolane ring group represented by the formula (b).

(In the formula (b),
n represents an integer of 0 to 7.
R represents a hydroxy group, an alkoxy group, or an aliphatic hydrocarbon group having 1 to 18 carbon atoms, and when n is 2 or more, a plurality of R may be the same or different and are each bonded to adjacent carbon atoms. Two Rs may combine to form a ring together with the carbon atom.
--- represents a single bond or a double bond.
* Is a bond with R ² . ]]
In addition, the group represented by the formula (a-1) is sometimes referred to as “group (a-1)”.

In the structural unit (a), R ¹ is preferably a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, more preferably a hydrogen atom or a methyl group.

In R ² , a hydroxy group, an alkoxy group having 1 to 6 carbon atoms, and the like are preferable as a substituent that is substituted with an aliphatic hydrocarbon group.
The group (a-1) includes a partial structure containing an oxygen atom such as an oxygen atom, a carbonyl group, a carbonyloxy group, or an oxycarbonyl group, as in X ¹⁰ and X ¹¹ .
As the group (a-1),

などが挙げられる。
なかでも、構造単位（ａ）のＲ^２としては、単結合、−ＣＨ_２−ＣＯ−Ｏ−＊又は−ＣＨ_２−ＣＨ_２−Ｏ−ＣＯ−＊（ここでの＊は、Ｒ^３との結合手である）が好ましい。

Etc.
Among them, as R ² of the structural unit (a), a single bond, —CH ₂ —CO—O— * or —CH ₂ —CH ₂ —O—CO— * (where * is the same as that of R ³ ) A bond).

［式（ｂ）中、
ｎは０〜７の整数を表す。
Ｒは、ヒドロキシ基、アルコキシ基又は炭素数１〜１８の脂肪族炭化水素基を表し、ｎが２以上の場合、複数のＲは同一でも異なっていてもよい。また、隣接する炭素原子に各々結合する２つのＲが結合して、前記炭素原子とともに環を形成してもよい。
---、つまり破線と直線との組み合わせは、単結合又は二重結合を表す。
＊は、Ｒ^２との結合手である。］ The sulfolane ring group in R ³ is a sultone ring group represented by the formula (b). Again, formula (b) is shown below.

[In the formula (b),
n represents an integer of 0 to 7.
R represents a hydroxy group, an alkoxy group, or an aliphatic hydrocarbon group having 1 to 18 carbon atoms, and when n is 2 or more, a plurality of R may be the same or different. Further, two Rs bonded to adjacent carbon atoms may be bonded to form a ring together with the carbon atoms.
--- That is, a combination of a broken line and a straight line represents a single bond or a double bond.
* Is a bond with R ² . ]

In the sulfolane ring group represented by the formula (b), at least one of the three carbon-carbon bonds represented by --- is preferably a double bond, and one carbon-carbon bond is a double bond. More preferably, it is a bond.
Examples of the ring formed by combining two Rs bonded to adjacent carbon atoms together with these carbon atoms include an aliphatic ring and an aromatic ring, and an aliphatic ring is preferred.
As such a ring, a cyclohexane ring, a norbornane ring, an oxanorbornane ring and the like are suitable.

［式（ｃ−１）〜式（ｃ−５）中、＊は、Ｒ^２との結合手を表す。］ R ³ is more preferably a sulfolane ring selected from the formulas (b-1) to (b-5).

[In formula (c-1) to formula (c-5), * represents a bond with R ² . ]

Examples of the structural unit (a) include the following.

In the structural unit (a) represented by any one of the formulas (a-1) to (a-19), the partial unit (M) shown below is replaced with the partial unit (A1). Specific examples of a) can be mentioned.

［式（ａｍ）中、Ｒ^１〜Ｒ^３は前記と同義である。］ The structural unit (a) is derived from a compound represented by the following formula (am) (hereinafter sometimes referred to as “compound (am)”).

[In the formula (am), R ^{1 to} R ³ are as defined above. ]

化合物（ａ１−ａ）としては、ヒドロキシエチルメタクリレートなどが挙げられる。このヒドロキシエチルメタクリレートは市場から容易に入手できる。
化合物（ａ１−ｂ）は、式（ａ１−ｃ）で表される化合物と式（ａ１−ｄ）で表される化合物とを、溶剤中で反応させることにより得ることができる。
ここで用いる溶剤としては、アセトニトリルが好ましい。

化合物（ａ１−ｃ）のうち、例えば、市場から容易に入手できるものを例示すると、以下の化合物などが挙げられる。

In the compound (am), the compound (am) in which R ² is —CH ₂ —CH ₂ —O—CO— is represented by, for example, the compound represented by the formula (a1-a) and the formula (a1-b). It can manufacture by making the compound made to react in a solvent.
As a solvent used here, acetonitrile is preferable.

Examples of the compound (a1-a) include hydroxyethyl methacrylate. This hydroxyethyl methacrylate is readily available from the market.
Compound (a1-b) can be obtained by reacting the compound represented by formula (a1-c) with the compound represented by formula (a1-d) in a solvent.
As a solvent used here, acetonitrile is preferable.

Examples of compounds (a1-c) that can be easily obtained from the market include the following compounds.

式（ａ２−ａ）で表される化合物としては、（メタ）アクリル酸クロリドなどが挙げられる。また、式（ａ２−ｂ）で表される化合物のうち、市場から容易に入手できるものを例示すると、以下の化合物などが挙げられる。

In the compound (am), the compound (am) in which R ² is a single bond is obtained by, for example, converting a compound represented by the formula (a2-a) and a compound represented by the formula (a2-b) into a basic catalyst. It can obtain by making it react in a solvent in presence of this. As a basic catalyst, triethylamine or the like is used. Examples of the solvent include tetrahydrofuran.

Examples of the compound represented by the formula (a2-a) include (meth) acrylic acid chloride. Moreover, the following compounds etc. are mentioned when what can be easily obtained from a market among the compounds represented by a formula (a2-b) is illustrated.

According to the production method described above, various compounds (am) can be produced as shown below.

（式（ａｍ’）中、Ｒ^２ｘは置換基を有していてもよい炭素数１〜６の脂肪族炭化水素基又は基（ａ−１）であり、その他の符号は前記と同義である。） As described above, among the exemplified compounds (am), the compound represented by the formula (am ′) (hereinafter, sometimes referred to as “compound (am ′)”) is useful if it can induce the structural unit (a). And it is a novel compound, and the present invention also provides such a compound (am ′).

(In the formula (am ′), R ^2x is an ^optionally substituted aliphatic hydrocarbon group or group (a-1) having 1 to 6 carbon atoms, and the other symbols are as defined above. .)

  The compound (am ′) is represented by the formula (am-6) to the formula (am-16) and the formula (am-21) to the formula (am-32) in the specific examples of the compound (am). Is applicable.

  The content ratio of the structural unit (a) to the total structural unit (100 mol%) of the resin (A) is preferably in the range of 2 to 40 mol%, more preferably in the range of 3 to 35 mol%, and more preferably 5 to 30 A range of mol% is more preferable.

  The resin (A) contained in the resist composition is preferably one having a characteristic that a resist pattern can be produced by a synergistic effect with the acid generator (B) described later. Examples of the resin having such characteristics include those that are insoluble or hardly soluble in an alkaline aqueous solution and are converted into a resin soluble in an alkaline aqueous solution by the action of an acid. Here, "being soluble in an alkaline aqueous solution by the action of an acid" means insoluble or hardly soluble in an alkaline aqueous solution before contact with an acid, but becomes soluble in an alkaline aqueous solution after contact with an acid. To do.

Accordingly, the resin (A) has the structural unit (a) and also has a structural unit (hereinafter, sometimes referred to as “structural unit (a1)”) that can exhibit a property of being converted into a resin soluble in an alkaline aqueous solution. It is preferable. Here, a resin having the property of being converted into a resin soluble in an alkaline aqueous solution is that a part or all of the hydrophilic group in the molecule of the resin is protected by a protecting group that can be removed by contact with an acid. It means a resin from which a protecting group is eliminated by contact with an acid. A hydrophilic group protected by such a protecting group is referred to as an “acid labile group”.
The resin (A) contained in the resist composition of the present invention is preferably a resin having one or more structural units (a) and one or more structural units (a1). A mixture of a resin having no structural unit (a1) and having the structural unit (a) and a resin having the structural unit (a1) may be used. In the latter case, the resin (A) may be one or more kinds of resins composed only of the structural unit (a), and has one or more kinds of structural units (a) and one or more kinds of other structural units. It may be a resin composed of one or more structural units, or may be a mixture of these one or more resins.

  This resist composition containing such a resin (A) can produce a resist pattern with an excellent focus margin (DOF) by the action of the resin (A) and an acid generator (B1) described later. it can. In addition, a resist pattern having excellent line edge roughness can be manufactured.

<Acid labile group>
First, representative examples of the acid labile group are shown.
Examples of the hydrophilic group include a hydroxy group or a carboxy group, and a carboxy group is more preferable. As described above, the resin (A) having an acid labile group is a structural unit (a1) having an acid labile group other than the structural unit (a) (hereinafter, in some cases, a monomer for deriving the structural unit (a1)). (Referred to as “monomer (a1)”).

式（１）中、
Ｒ^a1〜Ｒ^a3は、それぞれ独立に、炭素数１〜８の脂肪族炭化水素基を表すか、Ｒ^a1及びＲ^a2が結合して、それらが結合する炭素原子とともに炭素数３〜２０の環を形成し、Ｒ^a1及びＲ^a2が結合して形成される環及び該脂肪族炭化水素基を構成するメチレン基は、酸素原子、硫黄原子又はカルボニル基に置き換わっていてもよい。 In the case where the hydrophilic group is a carboxy group, the acid labile group is a group in which the hydrogen atom of the carboxy group is replaced with an organic residue, and the atom of the organic residue bonded to the oxygen atom of the carboxy group is a tertiary carbon atom Is mentioned. Among such acid labile groups, preferred acid labile groups are, for example, those represented by the following formula (1) (hereinafter sometimes referred to as “acid labile groups (1)”).

In formula (1),
R ^{a1 to} R ^a3 each independently represents an aliphatic hydrocarbon group having 1 to 8 carbon atoms, or R ^a1 and R ^a2 are bonded to each other, and a ring having 3 to 20 carbon atoms together with the carbon atom to which they are bonded. The ring formed by combining R ^a1 and R ^a2 and the methylene group constituting the aliphatic hydrocarbon group may be replaced with an oxygen atom, a sulfur atom or a carbonyl group.

このような環の炭素数は、好ましくは３〜１２である。 In the group represented by —C (R ^a1 ) (R ^a2 ) (R ^a3 ), examples of the ring formed by combining R ^a1 and R ^a2 include the following.

The number of carbon atoms in such a ring is preferably 3-12.

As such an acid labile group (1), for example,
1,1-dialkylalkoxycarbonyl group (in formula (1), R ^{a1 to} R ^a3 are all alkyl groups, and one of these alkyl groups is preferably a tert-butyl group),
2-alkyl-2-adamantyloxycarbonyl group (in the formula (1), R ^a1 and R ^a2 are bonded to each other to form an adamantane ring together with the carbon atom to which they are bonded, and R ^a3 is an alkyl group) and 1- (1-adamantyl) -1-alkylalkoxycarbonyl group (in the formula (1), R ^a1 and R ^a2 are alkyl groups, and R ^a3 is an adamantyl group).

式（２）中、
Ｒ^b1及びＲ^b2は、それぞれ独立に、水素原子又は炭素数１〜１２の炭化水素基を表し、Ｒ^b3は、炭素数１〜２０の炭化水素基を表すか、あるいはＲ^b2及びＲ^b3は互いに結合して、それらが各々結合する炭素原子及び酸素原子とともに炭素数３〜２０の環を形成し、前記環又は炭化水素基を構成するメチレン基は、酸素原子、硫黄原子又はカルボニル基に置き換わっていてもよい。
Ｒ^b2及びＲ^b3は互いに結合して形成される環は、Ｒ^a1及びＲ^a2が互いに結合して形成される環と同様のものが挙げられる。 Examples of the acid labile group in the case where the hydrophilic group is a hydroxy group include those in which a hydrogen atom of the hydroxy group is replaced with an organic residue to become a group containing an acetal structure. Such an acid labile group is preferably, for example, one represented by the following formula (2) (hereinafter sometimes referred to as “acid labile group (2)”).

In formula (2),
R ^b1 and R ^b2 each independently represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, R ^b3 represents a hydrocarbon group having 1 to 20 carbon atoms, or R ^b2 and R ^b3 are Bonded to each other to form a ring having 3 to 20 carbon atoms together with the carbon atom and oxygen atom to which they are bonded, and the methylene group constituting the ring or hydrocarbon group is replaced with an oxygen atom, a sulfur atom or a carbonyl group. It may be.
^Examples of the ring formed by combining R ^b2 and R ^b3 with each other include the same ring formed by combining R ^a1 and R ^a2 with each other.

In the formula (2), it is preferable that at least one of R ^b1 and R ^b2 is a hydrogen atom. Examples of the acid labile group (2) include the following groups.

The monomer (a1) having an acid labile group capable of deriving the structural unit (a1) is preferably a monomer having an acid labile group and a carbon-carbon double bond, more preferably an acid labile group. It is a (meth) acrylic monomer.
The monomer (a1) is preferably a monomer having both an acid labile group (1) and / or an acid labile group (2) and a carbon-carbon double bond in the molecule, and more preferably an acid-unstable group. It is a (meth) acrylic monomer having a stable group (1).

  Among the (meth) acrylic monomers having an acid labile group (1), the acid labile group (1) preferably has a cyclic aliphatic hydrocarbon having 5 to 20 carbon atoms as a partial structure. Resin (A) obtained by polymerizing the monomer (a1) having such a sterically bulky alicyclic group, when a resist pattern is produced using a resist composition containing this resin (A), A resist pattern can be manufactured with better resolution.

式（ａ１−１）及び式（ａ１−２）中、
Ｌ^a1及びＬ^a2は、それぞれ独立に、酸素原子又は^＊−Ｏ−（ＣＨ₂）_k1−ＣＯ−Ｏ−（ｋ１は１〜７の整数を表す）で表される基を表す。ここで、＊はカルボニル基（−ＣＯ−）との結合手である。
Ｒ^a4及びＲ^a5は、それぞれ独立に、水素原子又はメチル基を表す。
Ｒ^a6及びＲ^a7は、それぞれ独立に、炭素数１〜１０の脂肪族炭化水素基を表す。
ｍ１は０〜１４の整数を表し、ｎ１は０〜１０の整数を表し、ｎ２は０〜３の整数を表す。 Among structural units (a1) derived from a (meth) acrylic monomer having an acid labile group (1) having a partial structure of a cyclic aliphatic hydrocarbon, a structure represented by the formula (a1-1) A monomer giving a unit (hereinafter sometimes referred to as “structural unit (a1-1)”) or a structural unit represented by formula (a1-2) (hereinafter sometimes referred to as “structural unit (a1-2)”) The monomer provided is preferred. In producing the resin (A), these may be used alone or in combination of two or more.

In formula (a1-1) and formula (a1-2),
L ^a1 and L ^a2 each independently represent a group represented by an oxygen atom or ^* —O— (CH ₂ ) _k1 —CO—O— (k1 represents an integer of 1 to 7). Here, * is a bond with a carbonyl group (—CO—).
R ^a4 and R ^a5 each independently represent a hydrogen atom or a methyl group.
R ^a6 and R ^a7 each independently represents an aliphatic hydrocarbon group having 1 to 10 carbon atoms.
m1 represents an integer of 0 to 14, n1 represents an integer of 0 to 10, and n2 represents an integer of 0 to 3.

In the formula (a1-1) and the formula (a1-2), L ^a1 and L ^a2 are preferably oxygen atom or k1 is an integer of from 1 to 4 * -O- (CH _{2) k1} -CO- A group represented by O—, more preferably an oxygen atom or * —O—CH ₂ —CO—O—, and still more preferably an oxygen atom.
R ^a4 and R ^a5 are each preferably a methyl group.
R ^a6 and R ^a7 are each preferably an alkyl group having 1 to 8 carbon atoms or an alicyclic hydrocarbon group having 3 to 10 carbon atoms, more preferably an alkyl group having 1 to 8 carbon atoms or 3 carbon atoms. -8 alicyclic hydrocarbon group, more preferably an alkyl group having 1 to 6 carbon atoms or an alicyclic hydrocarbon group having 3 to 6 carbon atoms.
m1 is preferably an integer of 0 to 3, more preferably 0 or 1.
n1 is preferably an integer of 0 to 3, more preferably 0 or 1.
n2 is preferably an integer of 0 to 2, more preferably 0 or 1.

Examples of the structural unit represented by the formula (a1-1) include the following.

  In the specific example of the structural unit (a1-1) represented by any of the formulas (a1-1-1) to (a1-1-38), the partial structure (M) described above is changed to the partial structure (A1). What has been replaced can also be given as a specific example of the structural unit (a1-1).

  Among the specific examples of the structural unit (a1-1), a structure represented by any one of the formula (a1-1-1), the formula (a1-1-2), and the formula (a1-1-3) The unit (a1-1) and those obtained by substituting the partial structure (M1) of the structural unit (a1-1) with the partial structure (A1) are preferable, and are represented by the formulas (a1-1-1) and (a1-1). -2) and the structural unit (a1-1) represented by either the formula (a1-1-3) is more preferable, and any one of the formula (a1-1-1) and the formula (a1-1-2) The structural unit (a1-1) represented by In addition, resin (A) which has these preferable structural units (a1-1) is 2-methyl-2-adamantyl (meth) acrylate, 2-ethyl-2-adamantyl (meta) when manufacturing resin (A). ) Acrylate or 2-isopropyl-2-adamantyl (meth) acrylate or the like may be used as a raw material for production (monomer (a1)).

式（ａ１−２−１）〜式（ａ１−２−１２）のいずれかで表される構造単位（ａ１−２）の具体例において、上述したように、部分構造（Ｍ）を部分構造（Ａ１）に置き換えたものも構造単位（ａ１−２）の具体例として挙げることができる。 Examples of the structural unit represented by the formula (a1-2) include the following.

In the specific example of the structural unit (a1-2) represented by any one of the formulas (a1-2-1) to (a1-2-12), as described above, the partial structure (M) is converted into the partial structure ( Those substituted with A1) can also be mentioned as specific examples of the structural unit (a1-2).

  Among them, the structural unit (a1-2-1), the formula (a1-2-2), the formula (a1-2-4), and the formula (a1-2-5) represented by any one of the formulas (a1-2-1), (a1-2-2), (a1-2-5) 2) or those in which the partial structure (M) of the structural unit (a1-2) is replaced by the partial structure (A1), and the compounds represented by formulas (a1-2-4) and (a1-2-4) More preferably, the structural unit represented by any one of the structural units (a1) or the partial structure (M1-2) of these structural units (a1-2) is replaced by the partial structure (A1). In order to produce the resin (A) having such a structural unit (a1-2), 2-methyl-2-cyclohexyl (meth) acrylate or the like may be used as the monomer (a1).

  When the resin (A) having the structural unit (a1-1) and / or the structural unit (a1-2) is produced, these structural units are based on the total structural units (100 mol%) of the resin (A) obtained. Is preferably in the range of 10 to 95 mol%, more preferably in the range of 15 to 90 mol%, and still more preferably in the range of 20 to 85 mol%. In order to bring the total content of the structural unit (a1-1) and / or the structural unit (a1-2) into such a range, when the resin (A) is produced, What is necessary is just to adjust the usage-amount of the monomer (a1) which induce | derived the structural unit (a1-1) and / or the structural unit (a1-2).

式（ａ１−３）中、
Ｒ^a9は、水素原子、ヒドロキシ基を有していてもよい炭素数１〜３のアルキル基、カルボキシル基、シアノ基又は基−ＣＯＯＲ^a13（ここで、Ｒ^a13は、炭素数１〜２０の脂肪族炭化水素基を表し、該脂肪族炭化水素基に含まれる水素原子は、ヒドロキシ基に置換されていてもよく、該脂肪族炭化水素基を構成するメチレン基は、酸素原子又はカルボニル基に置き換わっていてもよい）を表す。
Ｒ^a10〜Ｒ^a12は、それぞれ独立に、炭素数１〜２０の脂肪族炭化水素基を表すか、或いは、Ｒ^a10及びＲ^a11が結合して、これらが結合している炭素原子とともに、炭素数３〜２０の環を形成し、脂肪族炭化水素基及び環を構成する水素原子は、ヒドロキシ基などで置換されていてもよく、該脂肪族炭化水素基及び環を構成するメチレン基は、酸素原子又はカルボニル基に置き換わっていてもよい。 The resin (A) has a structural unit (a1) [another structural unit (a1)] having an acid labile group other than the structural unit (a1-1) and the structural unit (a1-2). Also good.
Examples of such other structural unit (a1) are derived from a monomer having a norbornene ring represented by the following formula (a1-3) (hereinafter sometimes referred to as “monomer (a1-3)”). Can be mentioned.

In formula (a1-3),
R ^a9 is a hydrogen atom, an alkyl group having 1 to 3 carbon atoms which may have a hydroxy group, a carboxyl group, a cyano group or a group —COOR ^a13 (where R ^a13 is an aliphatic group having 1 to 20 carbon atoms) Represents a hydrocarbon group, a hydrogen atom contained in the aliphatic hydrocarbon group may be substituted with a hydroxy group, and a methylene group constituting the aliphatic hydrocarbon group is replaced with an oxygen atom or a carbonyl group. May be present).
R ^{a10 to} R ^a12 each independently represents an aliphatic hydrocarbon group having 1 to 20 carbon atoms, or R ^a10 and R ^a11 are bonded to each other together with the carbon atom to which these are bonded, The aliphatic hydrocarbon group and the hydrogen atom constituting the ring forming a ring of 3 to 20 may be substituted with a hydroxy group or the like, and the methylene group constituting the aliphatic hydrocarbon group and the ring is oxygen An atom or a carbonyl group may be substituted.

  Examples of the alkyl group having a hydroxy group include a hydroxymethyl group and a 2-hydroxyethyl group.

In formula (a1-3), R ^a13 is preferably an alkyl group having 1 to 8 carbon atoms or an alicyclic hydrocarbon group having 3 to 20 carbon atoms.
The ring formed by combining R ^a10 and R ^a11 is preferably an aliphatic ring, and specific examples include a cyclohexane ring and an adamantane ring.

  As the monomer (a1-3), for example, 5-norbornene-2-carboxylic acid-tert-butyl, 5-norbornene-2-carboxylic acid 1-cyclohexyl-1-methylethyl, 5-norbornene-2-carboxylic acid 1 -Methylcyclohexyl, 5-norbornene-2-carboxylic acid 2-methyl-2-adamantyl, 5-norbornene-2-carboxylic acid 2-ethyl-2-adamantyl, 5-norbornene-2-carboxylic acid 1- (4-methyl) Cyclohexyl) -1-methylethyl, 5-norbornene-2-carboxylic acid 1- (4-hydroxycyclohexyl) -1-methylethyl, 5-norbornene-2-carboxylic acid 1-methyl-1- (4-oxocyclohexyl) Ethyl and 5-norbornene-2-carboxylic acid 1- (1-adamantyl) -1-methyl Ethyl and the like.

  When the resin (A) is produced using the monomer (a1-3), the resin (A) includes a sterically bulky structural unit (a1) derived from the monomer (a1-3). Become. Thus, if a resist pattern is manufactured with this resist composition containing resin (A) which has a three-dimensionally bulky structural unit (a1), a resist pattern can be obtained with better resolution. Furthermore, since a rigid norbornane ring can be introduced into the main chain of the resin (A) by using the monomer (a1-3), this resist composition containing the resin (A) is a resist excellent in dry etching resistance. There is a tendency that a pattern is easily obtained.

  When the resin (A) has a structural unit derived from the monomer (a1-3), it is possible to produce a resist pattern with good resolution and from the viewpoint that a resist pattern excellent in dry etching resistance can be easily obtained. The content ratio of the structural unit derived from the monomer (a1-3) to the total structural unit (100 mol%) is preferably in the range of 10 to 95 mol%, more preferably in the range of 15 to 90 mol%. The range of 85 mol% is more preferable.

式（ａ１−４）中、
Ｒ^a32は、ハロゲン原子を有してもよい炭素数１〜６のアルキル基、水素原子又はハロゲン原子を表す。
Ｒ^a33は、ハロゲン原子、ヒドロキシ基、炭素数１〜６のアルキル基、炭素数１〜６のアルコキシ基、炭素数２〜４のアシル基、炭素数２〜４のアシルオキシ基、アクリロイル基又はメタクリロイル基を表す。
ｌａは０〜４の整数を表す。ｌａが２以上である場合、複数のＲ^a33は同一でも異なっていてもよい。
Ｒ^a34及びＲ^a35は、それぞれ独立に、水素原子又は炭素数１〜１２の炭化水素基を表す。
Ｘ^a2は、単結合又は置換基を有していていもよい炭素数１〜１７の脂肪族炭化水素基を表し、該脂肪族炭化水素基を構成するメチレン基は、酸素原子、硫黄原子、カルボニル基、スルホニル基又は−Ｎ（Ｒ^ｄ）−で示される基に置き換わっていてもよい。ここで、Ｒ^ｄは、水素原子又は炭素数１〜６のアルキル基を表す。
Ｙ^a3は、置換基を有していてもよい炭素数１〜１８の炭化水素基である。 Furthermore, as the monomer having an acid labile group (2), for example, a monomer represented by the following formula (a1-4) (hereinafter sometimes referred to as “monomer (a1-4)”) may be used.

In formula (a1-4),
R ^a32 represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom.
R ^a33 is a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an acyl group having 2 to 4 carbon atoms, an acyloxy group having 2 to 4 carbon atoms, an acryloyl group, or methacryloyl. Represents a group.
la represents an integer of 0 to 4. When la is 2 or more, the plurality of R ^a33 may be the same or different.
R ^a34 and R ^a35 each independently represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms.
X ^a2 represents a C 1-17 aliphatic hydrocarbon group which may have a single bond or a substituent, and the methylene group constituting the aliphatic hydrocarbon group includes an oxygen atom, a sulfur atom, a carbonyl The group may be replaced with a group, a sulfonyl group, or a group represented by -N (R ^d )-. Here, R ^d represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
Y ^a3 is an ^optionally substituted hydrocarbon group having 1 to 18 carbon atoms.

  Examples of the alkyl group having a halogen atom include a perfluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, a perfluoropentyl group, and a perfluorohexyl group. And haloalkyl groups such as perchloromethyl group, perbromomethyl group and periodiomethyl group.

In formula (a1-4), the alkyl group is preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group, and particularly preferably a methyl group.
As the alkoxy group, a methoxy group and an ethoxy group are more preferable, and a methoxy group is particularly preferable.
The aliphatic hydrocarbon group for X ^a2 is preferably a chain aliphatic hydrocarbon group, more preferably a saturated aliphatic hydrocarbon group, and still more preferably an alkanediyl group.
The hydrocarbon group for Y ^a3 is preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms.

Examples of the monomer (a1-4) include the following monomers.

ここに示すモノマー（ａ１−４）において、以下に示す部分構造（Ｖ）を部分構造（Ｐ）に置き換えたものもモノマー（ａ１−４）の具体例として挙げることができる。

In the monomer (a1-4) shown here, the partial structure (V) shown below can be replaced with the partial structure (P) as a specific example of the monomer (a1-4).

  When the resin (A) has a structural unit derived from the monomer (a1-4), the content ratio is in the range of 10 to 95 mol% with respect to the total structural unit (100 mol%) of the resin (A). Is preferable, the range of 15-90 mol% is more preferable, and the range of 20-85 mol% is further more preferable.

[式（ａ１−５）中、
Ｒ^３１は、ハロゲン原子を有してもよい炭素数１〜６のアルキル基又は水素原子、ハロゲン原子を表す。
Ｌ^１〜Ｌ^３は、オキシ基、チオキシ基又は^＊−Ｏ−（ＣＨ₂）_k1−ＣＯ−Ｏ−で表される基を表す。ここで、ｋ１は１〜７の整数を表し、＊はカルボニル基（−ＣＯ−）との結合手である。
Ｚ^１は、単結合又は炭素数１〜６のアルカンジイル基であり、該アルカンジイル基を構成するメチレン基は、オキシ基又はカルボニル基に置き換わっていてもよい。
ｓ１及びｓ２は、それぞれ独立して、０〜４の整数を表す。] Also in the monomer (a1) having an acid labile group (2), a (meth) acrylic monomer is preferable. As such a (meth) acrylic monomer, for example, a monomer represented by the formula (a1-5) (Hereinafter referred to as “monomer (a1-5)” in some cases).

[In the formula (a1-5),
R ³¹ represents a C 1-6 alkyl group which may have a halogen atom, a hydrogen atom, or a halogen atom.
L ^{1 to} L ³ represent a group represented by an oxy group, a thioxy group, or ^* —O— (CH ₂ ) _k1 —CO—O—. Here, k1 represents an integer of 1 to 7, and * is a bond with a carbonyl group (—CO—).
Z ¹ is a single bond or an alkanediyl group having 1 to 6 carbon atoms, and the methylene group constituting the alkanediyl group may be replaced with an oxy group or a carbonyl group.
s1 and s2 each independently represents an integer of 0 to 4. ]

In formula (a1-5), R ³¹ is preferably a hydrogen atom, a methyl group and a trifluoromethyl group, more preferably a hydrogen atom and a methyl group.
L ¹ is preferably an oxygen atom.
One of L ² and L ³ is preferably an oxygen atom and the other is a sulfur atom.
s1 is preferably 1.
As for s2, 0-2 are preferable.
Z ¹ is preferably a single bond or —CH ₂ —CO—O—.

As a monomer (a1-5), the following monomers are mentioned, for example.

ここに示すモノマー（ａ１−５）において、上述した部分構造（Ｐ）を部分構造（Ｖ）に置き換えたものもモノマー（ａ１−５）の具体例として挙げることができる。

In the monomer (a1-5) shown here, one in which the partial structure (P) described above is replaced with the partial structure (V) can also be given as a specific example of the monomer (a1-5).

  When the resin (A) has a structural unit (a1) derived from the monomer (a1-5), the content is 10 to 95 mol with respect to the total structural unit (100 mol%) of the resin (A). % Range is preferable, the range of 15-90 mol% is more preferable, and the range of 20-85 mol% is more preferable.

Furthermore, a monomer for deriving another structural unit having an acid labile group (1) and a carbon-carbon double bond in the molecule may be used for the production of the resin (A).
Examples of such a monomer include the following monomers.

  When the resin (A) has a structural unit derived from another acid labile monomer, the content ratio is 10 to 95 mol% with respect to the total structural unit (100 mol%) of the resin (A), Preferably it is 15-90 mol%, More preferably, it is 20-85 mol%.

The content ratio of the structural unit having an acid labile group to the total structural unit (100 mol%) of the resin (A) is preferably in the range of 10 to 80 mol%, more preferably in the range of 20 to 60 mol%. It is.
When the resin (A) contains the structural unit (a1) having an adamantane ring, particularly the structural unit (a1-1), the structural unit (a1-1) is used with respect to the total amount (100 mol%) of the structural unit (a1). ) Is preferably 15 mol% or more. By setting it as this range, there exists a tendency for the dry etching tolerance of the resist pattern obtained from this resist composition containing resin (A) to become more favorable.

<Acid stable structural unit>
Resin (A) has, in addition to structural unit (a) and structural unit (a1), a structural unit having no acid labile group (hereinafter, sometimes referred to as “acid-stable structural unit”). Is preferred.

  When the resin (A) has an acid stable structural unit, the ratio of the content ratio of the structural unit (a1) to the content ratio of the acid stable structural unit is [structural unit (a1)] / [acid stable structural unit]. In terms of expression, it is preferably 10 to 80 mol% / 90 to 20 mol%, and more preferably 20 to 60 mol% / 80 to 40 mol%. When the content ratio of the acid stable structural unit is determined based on the content ratio of the structural unit (a1), the structural ratio is calculated by including the structural unit (a) in the acid stable structural unit.

  The acid stable structural unit is preferably a structural unit having a hydroxy group or a lactone ring. An acid stable structural unit having a hydroxy group (hereinafter sometimes referred to as “acid stable structural unit (a2)”) and / or an acid stable structural unit having a lactone ring (hereinafter sometimes referred to as “acid stable structural unit (a3)”) When the resist composition containing the resin (A) is applied to a substrate, a coating film formed on the substrate or a composition layer obtained from the coating film is placed between the resin (A) and the substrate. It becomes easy to express excellent adhesiveness. In addition, this resist composition can produce a resist pattern with good resolution.

<Acid stable structural unit (a2)>
When the acid stable structural unit (a2) is introduced into the resin (A), each of the acid stable structural units (a2) depends on the type of exposure source used when producing a resist pattern from the resist composition containing the resin (A). 1) or 2 or more types can be selected. For example, when this resist composition is used for exposure using a high energy beam such as a KrF excimer laser (wavelength: 248 nm), an electron beam or EUV light as an exposure source, the acid stable structural unit (a2) is phenolic. It is preferable to introduce an acid stable structural unit (a2-0) having a hydroxyl group into the resin (A).
When using exposure using a short wavelength ArF excimer laser (wavelength: 193 nm) as an exposure source, an acid stable structural unit represented by the formula (a2-1) described later is used as a resin ( It is preferable to introduce into A).
In the following description, the monomer that derives the acid stable structural unit (a2) is referred to as “acid stable monomer (a2)”, and the monomer that derives the acid stable structural unit (a3) is referred to as “acid stable monomer (a3)”. That's it. In addition to the acid-stable monomer (a2) and acid-stable monomer (a3) mentioned here, monomers that derive an acid-stable structural unit such as the acid-stable monomer (a4) described later are collectively referred to as “acid-stable monomer”.

式（ａ２−０）中、
Ｒ^a30は、ハロゲン原子を有してもよい炭素数１〜６のアルキル基、水素原子又はハロゲン原子を表す。
Ｒ^a31は、ハロゲン原子、ヒドロキシ基、炭素数１〜６のアルキル基、炭素数１〜６のアルコキシ基、炭素数２〜４のアシル基、炭素数２〜４のアシルオキシ基、アクリロイル基又はメタクリロイル基を表す。
ｍａは０〜４の整数を表す。ｍａが２以上の整数である場合、複数のＲ^a31は同一でも異なっていてもよい。 <Acid stable structural unit (a2-0)>
Examples of the acid stable structural unit (a2) include those represented by the following formula (a2-0) (hereinafter sometimes referred to as “acid stable structural unit (a2-0)”).

In formula (a2-0),
R ^a30 represents a C 1-6 alkyl group which may have a halogen atom, a hydrogen atom or a halogen atom.
R ^a31 is a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an acyl group having 2 to 4 carbon atoms, an acyloxy group having 2 to 4 carbon atoms, an acryloyl group, or methacryloyl. Represents a group.
ma represents an integer of 0 to 4. When ma is an integer of 2 or more, the plurality of R ^a31 may be the same or different.

In Formula (a2-0), R ^a30 is preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group, and particularly preferably a methyl group.
R ^a31 is preferably an alkoxy group having 1 to 4 carbon atoms, more preferably a methoxy group or an ethoxy group, and particularly preferably a methoxy group.
ma is preferably 0, 1 or 2, more preferably 0 or 1, and particularly preferably 0.

ここに例示する具体例において、ベンゼン環に結合しているメチル基やエチル基を、Ｒ^a31として例示したその他の置換基に置き換えたものも、酸安定モノマー（ａ２−０）の具体例である。 Examples of the monomer that gives the acid stable structural unit (a2-0) (hereinafter sometimes referred to as “acid stable monomer (a2-0)”) include the following monomers.

In the specific examples illustrated here, those in which the methyl group or ethyl group bonded to the benzene ring is replaced with other substituents exemplified as R ^a31 are also specific examples of the acid stable monomer (a2-0). .

  When the resin (A) is produced using such an acid stable monomer (a2-0), a monomer in which the phenolic hydroxyl group in the acid stable monomer (a2-0) is protected with an appropriate protecting group Can also be used. As the protecting group here, for example, an acetyl group is preferred. Since the phenolic hydroxyl group protected with an acetyl group is deprotected by contact with an acid, it is deprotected from the precursor structural unit of the acid stable structural unit (a2-0) protected with an acetyl group. By doing so, an acid stable structural unit (a2-0) is obtained. However, since the resin (A) has the structural unit (a1) having an acid labile group as described above, when the precursor structural unit in which the phenolic hydroxyl group is protected with an appropriate protecting group is deprotected. In this case, it is necessary to carry out deprotection so that the acid labile group of the structural unit (a1) is not significantly impaired.

  As the acid stable monomer (a2-0), 4-hydroxystyrene or 4-hydroxy-α-methylstyrene is particularly preferable. When using these, when manufacturing resin (A), what protected the phenolic hydroxyl group in these with a suitable protective group can also be used.

  When resin (A) has an acid stable structural unit (a2-0), the content rate is chosen from the range of 5-95 mol% with respect to all the structural units (100 mol%) of resin (A). The range of 10-80 mol% is more preferable, and the range of 15-80 mol% is more preferable.

式（ａ２−１）中、
Ｌ^a3は、酸素原子又は^＊−Ｏ−（ＣＨ₂）_k2−ＣＯ−Ｏ−（ｋ２は１〜７の整数を表す。）を表し、＊はカルボニル基（−ＣＯ−）との結合手を表す。
Ｒ^a14は、水素原子又はメチル基を表す。
Ｒ^a15及びＲ^a16は、それぞれ独立に、水素原子、メチル基又はヒドロキシ基を表す。
ｏ１は、０〜１０の整数を表す。 <Acid stable structural unit (a2-1)>
The acid stable structural unit (a2-1) is represented by the following formula (a2-1).

In formula (a2-1),
L ^a3 represents an oxygen atom or ^* —O— (CH ₂ ) _k2 —CO—O— (k2 represents an integer of 1 to 7), and * represents a bond with a carbonyl group (—CO—). Represent.
R ^a14 represents a hydrogen atom or a methyl group.
R ^a15 and R ^a16 each independently represent a hydrogen atom, a methyl group or a hydroxy group.
o1 represents an integer of 0 to 10.

In the formula (a2-1), L ^a3 is preferably an oxygen atom or a group that k2 is represented there _{-O- (CH 2) k2 -CO-} O- in an integer of from 1 to 4, more preferably, an oxygen atom or, -O-CH ₂ -CO-O- and, still more preferably an oxygen atom.
R ^a14 is preferably a methyl group.
R ^a15 is preferably a hydrogen atom.
R ^a16 is preferably a hydrogen atom or a hydroxy group.
o1 is preferably an integer of 0 to 3, more preferably 0 or 1.

As an acid stable structural unit (a2-1), the following are mentioned, for example.

式（ａ２−１−１）〜式（ａ２−１−１７）のいずれかで表される酸安定構造単位（ａ２−１）の具体例において、部分構造（Ｍ）を部分構造（Ａ１）に置き換えたものも酸安定構造単位（ａ２−１）の具体例として挙げることができる。

In the specific example of the acid stable structural unit (a2-1) represented by any one of the formulas (a2-1-1) to (a2-1-17), the partial structure (M) is changed to the partial structure (A1). The substituted one can also be given as a specific example of the acid stable structural unit (a2-1).

  Among the acid stable structural units (a2-1), any one of the formula (a2-1-1), the formula (a2-1-2), the formula (a2-1-13) and the formula (a2-1-15) The acid stable structural unit (a2-1) represented by the formula (a2-1) and the partial structure (M1) of these acid stable structural units (a2-1) are preferably replaced by the partial structure (A1). The acid stable structural unit (a2-1) represented by any one of 1), formula (a2-1-2), formula (a2-1-13) and formula (a2-1-15) is more preferred. Resins (A) having these acid stable structural units (a2-1) are 3-hydroxy-1-adamantyl (meth) acrylate, 3,5-dihydroxy-1-adamantyl (meth) acrylate or (meth) acrylic acid 1- (3,5-dihydroxy-1-adamantyloxycarbonyl) methyl or the like may be used as a monomer for producing the resin (A).

  When the resin (A) has an acid stable structural unit (a2-1), the content ratio is preferably in the range of 3 to 45 mol% with respect to all the structural units (100 mol%) of the resin (A). The range of 5-40 mol% is more preferable, and the range of 5-35 mol% is more preferable.

<Acid stable structural unit (a3)>
The lactone ring included in the acid stable structural unit (a3) may be monocyclic such as β-propiolactone ring, γ-butyrolactone ring and δ-valerolactone ring, and the monocyclic lactone ring and other It may be a condensed ring with a ring. Among these lactone rings, a γ-butyrolactone ring and a condensed ring of a γ-butyrolactone ring and another ring are preferable.

［式（ａ３−１）〜式（ａ３−３）中、
Ｌ^a4〜Ｌ^a6は、それぞれ独立して、酸素原子又は^＊−Ｏ−（ＣＨ₂）_k3−ＣＯ−Ｏ−（ｋ３は１〜７の整数を表す。）を表す。＊はカルボニル基との結合手を表す。
Ｒ^a18〜Ｒ^a20は、それぞれ独立して、水素原子又はメチル基を表す。
Ｒ^a21は炭素数１〜４の脂肪族炭化水素基を表し、ｐ１が２以上の場合、複数のＲ^a21は同一でも異なっていてもよい。
Ｒ^a22及びＲ^a23は、それぞれ独立して、カルボキシ基、シアノ基又は炭素数１〜４の脂肪族炭化水素基を表し、ｑ１が２以上の場合、複数のＲ^a22は、同一でも異なっていてもよく、ｒ１が２以上の場合、複数のＲ^a23は、同一でも異なっていてもよい。
ｐ１は、０〜５の整数を表す。
ｑ１は、０〜３の整数を表す。
ｒ１は、０〜３の整数を表す。］ The acid stable structural unit (a3) is preferably represented by the following formula (a3-1), formula (a3-2) or formula (a3-3). Resin (A) may have only 1 type among these, and may have 2 or more types. In the following description, what is represented by the formula (a3-1) is referred to as “acid-stable structural unit (a3-1)”, and what is represented by the formula (a3-2) is “acid-stable structural unit ( a3-2) ”, and the compound represented by formula (a3-3) is referred to as“ acid-stable structural unit (a3-3) ”.

[In Formula (a3-1)-Formula (a3-3),
L ^{a4 to} L ^a6 each independently represents an oxygen atom or ^* —O— (CH ₂ ) _k3 —CO—O— (k3 represents an integer of 1 to 7). * Represents a bond with a carbonyl group.
R ^{a18 to} R ^a20 each independently represents a hydrogen atom or a methyl group.
R ^a21 represents an aliphatic hydrocarbon group having 1 to 4 carbon atoms, and when p1 is 2 or more, a plurality of R ^a21 may be the same or different.
R ^a22 and R ^a23 each independently represent a carboxy group, a cyano group, or an aliphatic hydrocarbon group having 1 to 4 carbon atoms, and when q1 is 2 or more, a plurality of R ^{a22 s} are the same or different. ^{Alternatively} , when r1 is 2 or more, the plurality of R ^a23 may be the same or different.
p1 represents an integer of 0 to 5.
q1 represents an integer of 0 to 3.
r1 represents an integer of 0 to 3. ]

In formula (a3-1) to formula (a3-3), L ^{a4 to} L ^a6 are each independently an oxygen atom or k3 is an integer of 1 to 4 * —O— (CH ₂ ) _k3 —CO— A group represented by O— is preferred, an oxygen atom or * —O—CH ₂ —CO—O— is more preferred, and an oxygen atom is more preferred.
R ^{a18 to} R ^a21 are preferably methyl groups.
R ^a22 and R ^a23 are each independently preferably a carboxy group, a cyano group or a methyl group.
p1, q1 and r1 are preferably integers of 0 to 2, more preferably 0 or 1.

Examples of the acid stable structural unit (a3-1) include the following.

Examples of the acid stable structural unit (a3-2) include the following.

式（ａ３−１−１）〜式（ａ３−１−１１）のいずれかで表される酸安定構造単位（ａ３−１）、式（ａ３−２−１）〜式（ａ３−２−１１）のいずれかで表される酸安定構造単位（ａ３−２）及び式（ａ３−３−１）〜式（ａ３−３−６）のいずれかで表される酸安定構造単位（ａ３−３）において、上述したように、部分構造（Ｍ）を部分構造（Ａ１）に置き換えたものも、各々酸安定構造単位（ａ３−１）、酸安定構造単位（ａ３−２）及び酸安定構造単位（ａ３−３）の具体例として挙げることができる。また、この例示において、ラクトン環が有する置換基（Ｒ^a21〜Ｒ^a23）としてメチル基を有するものも例示したが、このメチル基を上述のような基に置き換えたものも、酸安定構造単位（ａ３）の具体例として挙げられる。 Examples of the acid stable structural unit (a3-3) include the following.

The acid stable structural unit (a3-1) represented by any one of formula (a3-1-1) to formula (a3-1-11), formula (a3-2-1) to formula (a3-2-11) The acid stable structural unit (a3-2) represented by any one of the formula (a3-3-1) and the acid stable structural unit (a3-3) represented by any one of the formulas (a3-3-1) to (a3-3-6) ), In which the partial structure (M) is replaced with the partial structure (A1), the acid stable structural unit (a3-1), the acid stable structural unit (a3-2), and the acid stable structural unit, respectively, It can be mentioned as a specific example of (a3-3). Moreover, in this illustration, those having a methyl group as an example of the substituent (R ^{a21 to} R ^a23 ) of the lactone ring are also exemplified, but those in which this methyl group is replaced with the above-described groups are also acid stable structural units ( Specific examples of a3) are mentioned.

Among the acid stable structural units (a3), α- (meth) acryloyloxy-γ-butyrolactone, β- (meth) acryloyloxy-γ-butyrolactone, α- (meth) acryloyloxy-β, β-dimethyl-γ-butyrolactone, α -(Meth) acryloyloxy-α-methyl-γ-butyrolactone, β- (meth) acryloyloxy-α-methyl-γ-butyrolactone, (meth) acrylic acid (5-oxo-4-oxatricyclo [4.2.1 .0 ^3,7] nonane-2-yl, (meth) acrylic acid 2- tetrahydro-2-oxo-3-furyl, and (meth) acrylic acid (5-oxo-4-oxa-tricyclo [4.2.1 .0 ^3,7] nonane-2-yloxy) -2-oxoethyl acid derived from such stable structural unit (a3) is preferable.

  The resin (A) has an acid stable structural unit (a3) selected from the group consisting of an acid stable structural unit (a3-1), an acid stable structural unit (a3-2), and an acid stable structural unit (a3-3). In this case, the total content is selected from the range of 5 to 70 mol%, preferably 10 to 65 mol%, preferably 10 to 60 mol, based on the total structural unit (100 mol%) of the resin (A). % Range is more preferred.

式（ａ４−３）中、
Ｒ^a25及びＲ^a26は、それぞれ独立に、水素原子、ヒドロキシ基を有していてもよい炭素数１〜３のアルキル基、シアノ基、カルボキシ基又は基−ＣＯＯＲ^a27（ここで、Ｒ^a27は、炭素数１〜１８の脂肪族炭化水素基を表し、該脂肪族炭化水素基を構成するメチレン基は、酸素原子又はカルボニル基で置き換わっていてもよい。但し−ＣＯＯＲ^a27が酸不安定基となるものは除く（即ちＲ^a27は、３級炭素原子が−Ｏ−と結合するものを含まない））を表すか、或いはＲ^a25及びＲ^a26は互いに結合して−ＣＯ−Ｏ−ＣＯ−を形成する。 <Acid-stable monomer (a4)>
For the production of the resin (A), other acid stable monomers (a4) may be used.
The acid stable monomer (a4) is represented by maleic anhydride represented by the following formula (a4-1), itaconic anhydride represented by the formula (a4-2), and formula (a4-3). And an acid-stable monomer having a norbornene ring (hereinafter sometimes referred to as “acid-stable monomer (a4-3)”).

In formula (a4-3),
R ^a25 and R ^a26 each independently represent a hydrogen atom, an alkyl group having 1 to 3 carbon atoms which may have a hydroxy group, a cyano group, a carboxy group or a group —COOR ^a27 (wherein R ^a27 represents ^{Represents a C1-C18} aliphatic hydrocarbon group, and the methylene group constituting the aliphatic hydrocarbon group may be replaced by an oxygen atom or a carbonyl group, provided that -COOR ^a27 is an acid labile group. (i.e. R ^a27 may include not those tertiary carbon atom is bonded to -O-) except those represent a), or R ^a25 and R ^a26 are bonded to each other forming a -CO-O-CO- To do.

As the alkyl group which may have a hydroxy group, a methyl group, an ethyl group, a propyl group, a hydroxymethyl group, a 2-hydroxyethyl group and the like are preferable.
The aliphatic hydrocarbon group is preferably an alkyl group having 1 to 8 carbon atoms and an alicyclic hydrocarbon group having 4 to 18 carbon atoms, more preferably an alkyl group having 1 to 6 carbon atoms and 4 to 12 carbon atoms. And a methyl group, an ethyl group, a propyl group, a 2-oxo-oxolan-3-yl group, a 2-oxo-oxolan-4-yl group, and the like are more preferable.

  Examples of the acid stable monomer (a4-3) include 2-norbornene, 2-hydroxy-5-norbornene, 5-norbornene-2-carboxylic acid, methyl 5-norbornene-2-carboxylate, and 5-norbornene-2- Examples thereof include 2-hydroxy-1-ethyl carboxylate, 5-norbornene-2-methanol, 5-norbornene-2,3-dicarboxylic acid anhydride and the like.

  The resin (A) is a structural unit derived from maleic anhydride represented by the formula (a4-1), a structural unit derived from itaconic anhydride represented by the formula (a4-2), and an acid stable monomer (a4- In the case of having a structural unit selected from the group consisting of structural units derived from 3), the total content is from 2 to 40 mol% with respect to the total structural units (100 mol%) of the resin (A). The range of 3 to 30 mol% is preferable, and the range of 5 to 20 mol% is more preferable.

In the production of the resin (A), for example, a monomer having a fluorine atom as shown below (hereinafter sometimes referred to as “acid-stable monomer (a4-4)”) may be used.

Among such acid stable monomers (a4-4), (meth) acrylic acid 5- (3,3,3-trifluoro-2-hydroxy-) having a monocyclic or polycyclic alicyclic hydrocarbon 2- [trifluoromethyl] propyl) bicyclo [2.2.1] hept-2-yl, 6- (3,3,3-trifluoro-2-hydroxy-2- [trifluoromethyl) (meth) acrylic acid ] Propyl) bicyclo [2.2.1] hept-2-yl, 4,4-bis (trifluoromethyl) -3-oxatricyclo [4.2.1.0 ^2,5 ] (meth) acrylate Nonyl is preferred.

  When the resin (A) has a structural unit derived from the acid-stable monomer (a4-4), the total content is 1 to 20 mol relative to the total structural unit (100 mol%) of the resin (A). %, Preferably in the range of 2-15 mol%, more preferably in the range of 3-10 mol%.

［式（３）中、
Ｒ¹⁰は、炭素数１〜６のフッ化アルキル基を表す。］ For the production of the resin (A), an acid stable monomer (a4-5) having a group represented by the following formula (3) can also be used.

[In Formula (3),
R ¹⁰ represents a fluorinated alkyl group having 1 to 6 carbon atoms. ]

  Examples of the fluorinated alkyl group include difluoromethyl group, perfluoromethyl group, 1,1-difluoroethyl group, 2,2-difluoroethyl group, 2,2,2-trifluoroethyl group, perfluoroethyl group, 1, 1,2,2-tetrafluoropropyl group, 1,1,2,2,3,3-hexafluoropropyl group, perfluoroethylmethyl group, 1- (trifluoromethyl) -1,2,2,2- Tetrafluoroethyl group, perfluoropropyl group, 1,1,2,2-tetrafluorobutyl group, 1,1,2,2,3,3-hexafluorobutyl group, 1,1,2,2,3, 3,4,4-octafluorobutyl group, perfluorobutyl group, 1,1-bis (trifluoro) methyl-2,2,2-trifluoroethyl group, 2- (perfluoropropyl) ethyl group, , 1,2,2,3,3,4,4-octafluoropentyl group, perfluoropentyl group, 1,1,2,2,3,3,4,4,5,5-decafluoropentyl group, 1,1-bis (trifluoromethyl) -2,2,3,3,3-pentafluoropropyl group, perfluoropentyl group, 2- (perfluorobutyl) ethyl group, 1,1,2,2,3 , 3,4,4,5,5-decafluorohexyl group, 1,1,2,2,3,3,4,4,5,5,6,6-dodecafluorohexyl group, perfluoropentylmethyl group And perfluorohexyl groups.

  In the formula (3), the fluorinated alkyl group preferably has 1 to 4 carbon atoms, more preferably a perfluoromethyl group, a perfluoroethyl group, and a perfluoropropyl group, and particularly preferably a perfluoromethyl group.

As an acid stable monomer (a4-5), what is represented by the following is mentioned, for example.

ここに示した酸安定モノマー（ａ４−５）の具体例において、上述した部分構造（Ｐ）を、部分構造（Ｖ）に置き換えたものも、酸安定モノマー（ａ４−５）の具体例として挙げることができる。

In the specific examples of the acid-stable monomer (a4-5) shown here, those obtained by replacing the partial structure (P) with the partial structure (V) are also given as specific examples of the acid-stable monomer (a4-5). be able to.

  When the resin (A) has a structural unit derived from the acid-stable monomer (a4-5), the content is 1 to 30 mol% with respect to the total structural unit (100 mol%) of the resin (A). The range of 3 to 25 mol% is preferable, and the range of 5 to 20 mol% is more preferable.

［式（４）中、
Ｒ¹¹は置換基を有してもよい炭素数６〜１２の芳香族炭化水素基を表す。
Ｒ¹²は、置換基を有してもよい炭素数１〜１２の炭化水素基を表し、該炭化水素基は、ヘテロ原子を含んでいてもよい。
Ａ^３は、単結合、−（ＣＨ_２）_ｍ10−ＳＯ_２−Ｏ−＊又は−（ＣＨ_２）_ｍ10−ＣＯ−Ｏ−＊を表し、ここに示すアルキレン鎖〔−（ＣＨ_２）_ｍ10−〕を構成するメチレン基は、酸素原子、カルボニル基又はスルホニル基に置き換わっていてもよく、当該アルキレン鎖に含まれる水素原子は、フッ素原子に置き換わっていてもよい。
ｍ１０は、１〜１２の整数を表す。］ For the production of the resin (A), an acid stable monomer (a4) having a group represented by the following formula (4) can also be used.

[In Formula (4),
R ¹¹ represents an aromatic hydrocarbon group having 6 to 12 carbon atoms which may have a substituent.
R ¹² represents an optionally substituted hydrocarbon group having 1 to 12 carbon atoms, and the hydrocarbon group may contain a hetero atom.
A ³ represents a single bond, — (CH ₂ ) _{m 10} —SO ₂ —O— * or — (CH ₂ ) _{m 10} —CO—O— *, and an alkylene chain [— (CH ₂ ) _{m 10} —] shown here. May be replaced with an oxygen atom, a carbonyl group or a sulfonyl group, and a hydrogen atom contained in the alkylene chain may be replaced with a fluorine atom.
m10 represents an integer of 1 to 12. ]

Examples of the substituent of the aromatic hydrocarbon group in R ¹¹ include an alkyl group having 1 to 4 carbon atoms, a halogen atom, a phenyl group, a nitro group, a cyano group, a hydroxy group, a phenyloxy group, and a tert-butylphenyl group. It is done.

Examples of R ¹¹ include the following. * A bond with a carbon atom.

Examples of the hetero atom that the hydrocarbon in R ¹² may contain include a halogen atom, a sulfur atom, an oxygen atom, and a nitrogen atom. Moreover, the form containing a sulfonyl group and a carbonyl group as a coupling group may be sufficient.
Examples of R ¹² containing such a heteroatom include the following groups.

Examples of A ³ include the following groups.

［式（ａ４−６）中、
Ｒ¹³は、水素原子又はメチル基を表す。
Ｒ¹¹、Ｒ¹²及びＡ^３は、前記と同義である。］ As an acid stable monomer (a4) containing group represented by Formula (4), the acid stable monomer represented by Formula (a4-6) is mentioned, for example.

[In the formula (a4-6),
R ¹³ represents a hydrogen atom or a methyl group.
R ¹¹ , R ¹² and A ³ are as defined above. ]

ここに示した酸安定モノマー（ａ４−６）の具体例において、上述したように、部分構造（Ｖ）を部分構造（Ｐ）に置き換えたものもモノマー（ａ４−６）の具体例として挙げることができる。 As an acid stable monomer (a4-6), the following are mentioned, for example.

In the specific example of the acid-stable monomer (a4-6) shown here, as described above, the partial structure (V) is replaced with the partial structure (P) as a specific example of the monomer (a4-6). Can do.

  When the resin (A) has a structural unit derived from the acid-stable monomer (a4-6), the content is 1 to 30 mol% with respect to the total structural unit (100 mol%) of the resin (A). The range of 3 to 25 mol% is preferable, and the range of 5 to 20 mol% is more preferable.

［式（ａ４−７）中、
環Ｗ^２は、炭素数３〜３６の環式脂肪族炭化水素を表す。
Ａ^４は、単結合又は炭素数１〜１７の脂肪族炭化水素基を表し、該脂肪族炭化水素基を構成するメチレン基は、酸素原子又はカルボニル基に置き換わっていてもよいが、Ａ^４のうち、酸素原子に結合している原子は炭素原子である。
Ｒ¹⁴は、水素原子、ハロゲン原子、炭素数１〜６のアルキル基又は炭素数１〜６のハロアルキル基を表す。
Ｒ¹⁵及びＲ¹⁶は、それぞれ独立に、炭素数１〜６のアルキル基又は炭素数１〜６のハロアルキル基を表す。］ Furthermore, as the acid stable monomer (a4), for example, a monomer represented by the following formula (a4-7) may be used.

[In the formula (a4-7),
Ring ^{W 2} represents a cyclic aliphatic hydrocarbon of 3 to 36 carbon atoms.
A ⁴ represents an aliphatic hydrocarbon group of a single bond or a C 1-17 methylene groups constituting the aliphatic hydrocarbon group may but be replaced by an oxygen atom or a carbonyl group, the A ⁴ Of these, the atom bonded to the oxygen atom is a carbon atom.
R ¹⁴ represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, or a haloalkyl group having 1 to 6 carbon atoms.
R ¹⁵ and R ¹⁶ each independently represents an alkyl group having 1 to 6 carbon atoms or a haloalkyl group having 1 to 6 carbon atoms. ]

で示される部分構造は、式（ＫＡ−１）〜式（ＫＡ−１９）の脂環式炭化水素を構成する水素原子の１個がＡ^４との結合手に、脂環式炭化水素の環原子である炭素原子の１つに結合している２つの水素原子が、−Ｏ−ＣＯ−Ｒ¹⁵又は−Ｏ−ＣＯ−Ｒ¹⁶との結合手に置き換わったものを挙げることができる。
Ｗ^２としては、シクロヘキサン環、アダマンタン環及びノルボルネン環が特に好ましい。 In formula (A4-7), the ring ^{W 2} has a carbon number of preferably cycloaliphatic hydrocarbons having 5 to 18, 6 to 12 more preferably in the range of. Specifically, the alicyclic hydrocarbon shown by the formula (KA-1)-the formula (KA-19) mentioned above is mentioned. That is, in formula (a4-7),

In the partial structure represented by the formula (KA-1) to (KA-19), one of the hydrogen atoms constituting the alicyclic hydrocarbon in the bond to A ⁴ is a ring of the alicyclic hydrocarbon. two hydrogen atoms bonded to one carbon atom is an atom that, there may be mentioned those replaced by bond to -O-CO-R ¹⁵ or -O-CO-R ^16.
As W ² , a cyclohexane ring, an adamantane ring and a norbornene ring are particularly preferable.

式中、
Ｘ^X1及びＸ^X2は、それぞれ独立に、単結合又は置換基を有していてもよい炭素数１〜６のアルカンジイル基を表し、Ｘ^X1及びＸ^X2がともに単結合であることはなく、式（Ｘ^ｘ−Ａ）、式（Ｘ^ｘ−Ｂ）及び式（Ｘ^ｘ−Ｃ）で表される基の総炭素数は１７以下である。 As the substituent in the aliphatic hydrocarbon group for A ⁴ , for example, a halogen atom, an alkoxy group, an alkylthio group, an acyl group, an aryl group, an aralkyl group, and an aryloxy group are preferable.
The A ^4, for example, it has suitable aliphatic hydrocarbon group formed by combining alkanediyl group and an alicyclic hydrocarbon group. Examples of such an aliphatic hydrocarbon group include groups represented by the following formula (X ^x -A), formula (X ^x -B), and formula (X ^x -C).

Where
X ^X1 and X ^X2 each independently represent a single bond or an alkanediyl group having 1 to 6 carbon atoms which may have a substituent, and X ^X1 and X ^X2 are not single bonds, The total number of carbon atoms of the groups represented by formula (X ^x -A), formula (X ^x -B), and formula (X ^x -C) is 17 or less.

Examples of the group in which the methylene group constituting the aliphatic hydrocarbon group in A ⁴ is replaced with an oxygen atom or a carbonyl group include those exemplified for the group (a-1) in the formula (a).
Among them, ^{A 4} represents a single bond or _* - represented by (* represents a binding position to -O-, s1 is an integer of _{1~6.) - (CH 2)} s1 -CO-O A group is preferable, and a group represented by a single bond or * —CH ₂ —CO—O— (* represents a bond to —O—) is more preferable.

R ¹⁴ is preferably a hydrogen atom or a methyl group.
As the halogen atom in R ^{14 to} R ¹⁶ , a fluorine atom is particularly preferable.
Of the haloalkyl groups of R ¹⁴ and R ¹⁶ , a perfluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluorobutyl group, and the like are preferable, and a perfluoromethyl group, a perfluoroethyl group, and a perfluoropropyl group are more preferable. .

Examples of the acid stable monomer (a4-7) include those shown below. R ^{14 to} R ¹⁶ and A ⁴ have the same meanings as described above.

で示されるモノマーがより好ましい。 Among these,

The monomer shown by is more preferable.

ここに示した酸安定モノマー（ａ４−７）の具体例において、上述したように、部分構造（Ｐ）を部分構造（Ｖ）に置き換えたものも、酸安定モノマー（ａ４−７）の具体例として挙げられる。 Examples of the acid stable monomer (a4-7) include the following.

In the specific example of the acid stable monomer (a4-7) shown here, as described above, the partial structure (P) is replaced with the partial structure (V). As mentioned.

［式（ａ４−７−ａ）及び式（ａ４−７−ｂ）中
Ｗ^２、Ａ^４、Ｒ^１４、Ｒ^１５及びＲ^１６は、前記と同義である。］ The acid stable monomer (a4-7) can be produced by reacting the compound represented by the formula (a4-7-a) with the compound represented by the formula (a4-7-b).
Examples of the compound represented by the formula (a4-7-a) include 1-methacryloyloxy-4-oxoadamantane described in JP-A-2002-226436. Examples of the compound represented by the formula (a4-7-b) include pentafluoropropionic anhydride, heptafluorobutyric anhydride, and trifluoroacetic anhydride. This reaction is preferably carried out by heating near the boiling point of the compound represented by the formula (a4-7-b) to be used.

[W ² , A ⁴ , R ¹⁴ , R ¹⁵ and R ¹⁶ in the formula (a4-7-a) and the formula (a4-7-b) have the same meanings as described above. ]

  When the resin (A) has a structural unit derived from the acid-stable monomer (a4-7), the content is 1 to 30 mol% with respect to the total structural unit (100 mol%) of the resin (AA). The range of 3 to 25 mol% is preferable, and the range of 5 to 20 mol% is more preferable.

<Manufacture of resin>
The resin (A) can be produced by polymerizing the compound (am) [compound (am ′)], the monomer (a1), and, if necessary, an acid stable monomer. More preferably, it can be produced by copolymerizing the compound (a ′), the monomer (a1), the acid stable monomer (a2) and / or the acid stable monomer (a3).
In the case of producing the resin (A), as the monomer (a1), the monomer (a1) having an adamantyl group [the monomer (a1) deriving the structural unit (a1-1)] and the monomer (a1) having a cyclohexyl group Among [monomer (a1) for deriving structural unit (a1-2)], it is preferable to use at least one, and it is more preferable to use monomer (a1) for deriving structural unit (a1-1). As an acid stable monomer, a monomer [acid stable monomer (a2)] for deriving acid stable structural unit (a2-1) and a monomer [acid stable monomer (a3)] for deriving acid stable structural unit (a3) are used. Is preferred. As the acid stable monomer (a3), it is preferable to use an acid stable monomer that derives at least one of an acid stable structural unit (a3-1) and an acid stable structural unit (a3-2). The resin (A) can be produced by subjecting such a monomer to a known polymerization method (for example, radical polymerization method).

  The weight average molecular weight of the resin (A) is preferably 2,500 or more and 50,000 or less, and more preferably 3,000 or more and 30,000 or less. In addition, the weight average molecular weight here is calculated | required as a conversion value of a standard polystyrene reference | standard by gel permeation chromatography analysis, and the detailed analysis conditions of this analysis are explained in full detail in the Example of this application.

式（Ｂ１）中、
Ｑ¹及びＱ²は、それぞれ独立に、フッ素原子又は炭素数１〜６のペルフルオロアルキル基を表す。
Ｌ^b1は、置換基を有していてもよい炭素数１〜１７の脂肪族炭化水素基を表し、該脂肪族炭化水素基を構成するメチレン基は、酸素原子又はカルボニル基に置き換わっていてもよい。
Ｙは、置換基を有していてもよい炭素数１〜１８の脂肪族炭化水素基を表し、該脂肪族炭化水素基を構成するメチレン基は、酸素原子、カルボニル基又はスルホニル基に置き換わっていてもよい。
Ｚ⁺は、有機カチオンを表す。 <Acid generator (B1)>
The acid generator (B1) is a sulfonate salt represented by the formula (B1). Again, formula (B1) is shown below.

In formula (B1),
Q ¹ and Q ² each independently represents a fluorine atom or a C 1-6 perfluoroalkyl group.
L ^b1 represents an ^optionally substituted aliphatic hydrocarbon group having 1 to 17 carbon atoms, and the methylene group constituting the aliphatic hydrocarbon group may be replaced by an oxygen atom or a carbonyl group. Good.
Y represents an optionally substituted aliphatic hydrocarbon group having 1 to 18 carbon atoms, and the methylene group constituting the aliphatic hydrocarbon group is replaced by an oxygen atom, a carbonyl group or a sulfonyl group. May be.
Z ⁺ represents an organic cation.

Examples of the perfluoroalkyl group include a perfluoroalkyl group in a fluorinated alkyl group.
In the formula (B1), Q ¹ and Q ² are each independently preferably a trifluoromethyl group or a fluorine atom, and both Q ¹ and Q ² are more preferably a fluorine atom.

式（ｂ１−１）〜式（ｂ１−６）中、
Ｌ^b2は、単結合又は炭素数１〜１５の脂肪族炭化水素基を表す。
Ｌ^b3は、単結合又は炭素数１〜１２の脂肪族炭化水素基を表す。
Ｌ^b4は、炭素数１〜１３の脂肪族炭化水素基を表し、Ｌ^b3及びＬ^b4の合計炭素数の上限は１３である。
Ｌ^b5は、炭素数１〜１５の脂肪族炭化水素基を表す。
Ｌ^b6及びＬ^b7は、それぞれ独立に、炭素数１〜１５の脂肪族炭化水素基を表し、Ｌ^b6及びＬ^b7の合計炭素数の上限は１６である。
Ｌ^b8は、炭素数１〜１４の脂肪族炭化水素基を表す。
Ｌ^b9及びＬ^b10は、それぞれ独立に、炭素数１〜１１の脂肪族炭化水素基を表し、Ｌ^b9及びＬ^b10の合計炭素数の上限は１２である。 Methylene group constituting the aliphatic hydrocarbon group for L ^b1 is, those which replaced by an oxygen atom or a carbonyl group, for example, represented by any one of the following formulas (b1-1) ~ formula (b1-6) Groups. Incidentally, the formula (b1-1) ~ formula (b1-6) has its left and right are described in accordance with the formula (B1), the left bond ^{is, C (Q 1) (Q} 2) coupled with and The right hand is connected to Y. The same applies to specific examples of the following formulas (b1-1) to (b1-6). * Represents a bond, one bonded to Y and the other bonded to a carbon atom of CQ ¹ Q ² .

In formula (b1-1) to formula (b1-6),
L ^b2 represents a single bond or an aliphatic hydrocarbon group having 1 to 15 carbon atoms.
L ^b3 represents a single bond or an aliphatic hydrocarbon group having 1 to 12 carbon atoms.
L ^b4 represents an aliphatic hydrocarbon group having 1 to 13 carbon atoms, and the upper limit of the total carbon number of L ^b3 and L ^b4 is 13.
L ^b5 represents an aliphatic hydrocarbon group having 1 to 15 carbon atoms.
L ^b6 and L ^b7 each independently represent an aliphatic hydrocarbon group having 1 to 15 carbon atoms, and the upper limit of the total carbon number of L ^b6 and L ^b7 is 16.
L ^b8 represents an aliphatic hydrocarbon group having 1 to 14 carbon atoms.
L ^b9 and L ^b10 each independently represent an aliphatic hydrocarbon group having 1 to 11 carbon atoms, and the upper limit of the total carbon number of L ^b9 and L ^b10 is 12.

As for bivalent group represented by a formula (b1-1), the following are mentioned, for example.

Examples of the divalent group represented by the formula (b1-2) include the following.

Examples of the divalent group represented by the formula (b1-3) include the following.

Examples of the divalent group represented by the formula (b1-4) include the following.

Examples of the divalent group represented by the formula (b1-5) include the following.

Examples of the divalent group represented by the formula (b1-6) include the following.

L ^b1 is preferably a group represented by any one of formulas (b1-1) to (b1-4), and more preferably any one of formulas (b1-1) to (b1-3). It is a group represented.
Among these, as L ^b1 , a divalent group represented by the formula (b1-1) and a divalent group represented by the formula (b1-1) in which L ^b2 is a single bond or a methylene group are more preferable. .

Examples of the substituent of the aliphatic hydrocarbon group in L ^b1 include a halogen atom, a hydroxy group, a carboxy group, an aromatic hydrocarbon group having 6 to 18 carbon atoms, an aralkyl group having 7 to 21 carbon atoms, and 2 to 2 carbon atoms. 4 acyl groups and glycidyloxy groups.

Y is preferably an alkyl group and an alicyclic hydrocarbon group, more preferably an alkyl group having 1 to 6 carbon atoms and an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and an alicyclic hydrocarbon having 3 to 12 carbon atoms. The group is particularly preferred.
Examples of the substituent of the aliphatic hydrocarbon group in Y include, for example, a halogen atom (excluding a fluorine atom), a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, A aralkyl group having 7 to 21 carbon atoms, an acyl group having 2 to 4 carbon atoms, a glycidyloxy group or a group represented by — (CH ₂ ) _j2 —O—CO—R ^b1 (wherein R ^b1 is the number of carbon atoms) Represents a hydrocarbon group of 1 to 16. j2 represents an integer of 0 to 4). Here, the aromatic hydrocarbon group and the aralkyl group may further have, for example, an alkyl group, a halogen atom or a hydroxy group.
Examples of the group in which the methylene group constituting the aliphatic hydrocarbon group of Y is replaced by an oxygen atom, a sulfonyl group or a carbonyl group include a cyclic ether group (one or two of the methylene groups constituting the alicyclic hydrocarbon group). One is replaced by an oxygen atom), a cyclic ketone group (a group in which one or two of the methylene groups constituting the alicyclic hydrocarbon group are replaced by a carbonyl group), a sultone ring group (which forms an alicyclic hydrocarbon group) Of two methylene groups adjacent to each other are groups in which oxygen atoms and sulfonyl groups are replaced, respectively, and lactone ring groups (methylene groups constituting alicyclic hydrocarbon groups are adjacent to each other). , Groups in which oxygen atoms and carbonyl groups are substituted, respectively).

A preferred group of the alicyclic hydrocarbon group of Y is an alicyclic hydrocarbon group represented by any of the following formulas (Y1) to (Y5), and among these, the formula (Y1), The alicyclic hydrocarbon group represented by any one of the formula (Y2), the formula (Y3) and the formula (Y5) is more preferable, and the alicyclic represented by any one of the formula (Y1) and the formula (Y2). A hydrocarbon group is particularly preferred.

なかでも、Ｙとしては、ヒドロキシアダマンチル基が特に好ましい。 Specific examples of the alicyclic hydrocarbon group having a substituent are as follows.

Among these, as Y, a hydroxyadamantyl group is particularly preferable.

As a sulfonate anion which comprises an acid generator (B1), what is represented by a formula (b1-1-1)-a formula (b1-1-9) is mentioned, for example. In the sulfonate anion represented by any one of formulas (b1-1-1) to (b1-1-9), L ^b1 is preferably a group represented by formula (b1-1). R ^b2 and R ^b3 are each independently defined as a substituent that may optionally be present in the aliphatic hydrocarbon group of Y, preferably an aliphatic hydrocarbon group having 1 to 4 carbon atoms, A methyl group is particularly preferred.

  Specific examples of the sulfonate anion represented by any one of the formulas (b1-1-1) to (b1-1-9) include sulfonate anions described in JP 2010-204646 A, for example. be able to.

As the sulfonate anion, L ^b1 is preferably a group represented by the formula (b1-1), and Y is an alicyclic hydrocarbon group represented by the formula (Y1) or the formula (Y2). .
Examples of the sulfonate anion in which Y is an unsubstituted alicyclic hydrocarbon group include those represented by any of the following formulas (b1-s-1) to (b1-s-9).

Examples of the sulfonate anion in which Y is an alicyclic hydrocarbon group having a hydroxy group include those represented by any of the following formulas (b1-s-10) to (b1-s-18). .

Examples of the sulfonate anion in which Y is a cyclic ketone group include those represented by any of the following formulas (b1-s-19) to (b1-s-29).

Examples of the sulfonate anion in which Y is an alicyclic hydrocarbon group having an aromatic group include those represented by any of the following formulas (b1-s-30) to (b1-s-35). It is done.

Examples of the sulfonate anion in which Y is the lactone ring group or the sulfonic acid ring group include those represented by any of the following formulas (b1-s-36) to (b1-s-41). It is done.

Y may be an alkyl group. Examples of such a sulfonate anion include those represented by the following formula (b1-s-42).

Examples of the organic cation (Z ⁺ ) in the acid generator (B1) include an onium cation, a sulfonium cation, an iodonium cation, an ammonium cation, a benzothiazolium cation, and a phosphonium cation. Among these, a sulfonium cation and an iodonium cation are preferable, a sulfonium cation and an iodonium cation are preferable, and an organic cation represented by any of the following formulas (b2-1) to (b2-4) is more preferable. .

In formula (b2-1) to formula (b2-4),
R ^{b4 to} R ^b6 each independently represents a hydrocarbon group having 1 to 30 carbon atoms, and among these hydrocarbon groups, an alkyl group having 1 to 30 carbon atoms and an alicyclic carbonization having 3 to 18 carbon atoms. A hydrogen group and an aromatic hydrocarbon group having 6 to 18 carbon atoms are preferred. R ^b4 and R ^b5 may be combined to form a ring that may have a hetero atom. The alkyl group may have a hydroxy group, an alkoxy group having 1 to 12 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and the alicyclic hydrocarbon group includes a halogen atom and a carbon number. It may have 2 to 4 acyl groups or glycidyloxy groups, and the aromatic hydrocarbon group is a halogen atom, a hydroxy group, an alkyl group having 1 to 18 carbon atoms, or a saturated cyclic carbonization having 3 to 18 carbon atoms. You may have a hydrogen group or a C1-C12 alkoxy group.
R ^b7 and R ^b8 each independently represent a hydroxy group, an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms.
m2 and n2 each independently represent an integer of 0 to 5.
R ^b9 and R ^b10 each independently represent an alkyl group having 1 to 18 carbon atoms or an alicyclic hydrocarbon group having 3 to 18 carbon atoms.
R ^b11 represents a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms.
R ^{b9 to} R ^b11 are each independently an aliphatic hydrocarbon group, and when the aliphatic hydrocarbon group is an alkyl group, the number of carbon atoms is preferably 1 to 12, and the aliphatic hydrocarbon group Is an alicyclic hydrocarbon group, the carbon number thereof is preferably 3 to 18, and more preferably 4 to 12.
R ^b12 represents a hydrocarbon group having 1 to 18 carbon atoms. Among these hydrocarbon groups, the aromatic hydrocarbon group is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or 1 to 12 carbon atoms. It may have an alkylcarbonyloxy group.
R ^b9 and R ^b10 and / or R ^b11 and R ^b12 may be independently bonded to each other to form a 3- to 12-membered ring (preferably a 3- to 7-membered ring). In the 3-membered ring to 12-membered ring (preferably 3-membered ring to 7-membered ring), an alicyclic hydrocarbon or a methylene group constituting the alicyclic hydrocarbon is replaced with an oxygen atom, a sulfur atom or a carbonyl group. It is a ring.

R ^{b13 to} R ^b18 each independently represent a hydroxy group, an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms.
L ^b11 represents an oxygen atom or a sulfur atom.
o2, p2, s2, and t2 each independently represents an integer of 0 to 5.
q2 and r2 each independently represents an integer of 0 to 4.
u2 represents 0 or 1.
When o2 is 2 or more, the plurality of R ^b13 may be the same or different. When p2 is 2 or more, the plurality of R ^b14 may be the same or different. When s2 is 2 or more, The plurality of R ^b15 may be the same or different, and when t2 is 2 or more, the plurality of R ^b15 may be the same or different.

  Examples of the alkylcarbonyloxy group include a methylcarbonyloxy group, an ethylcarbonyloxy group, an n-propylcarbonyloxy group, an isopropylcarbonyloxy group, an n-butylcarbonyloxy group, a sec-butylcarbonyloxy group, a tert-butylcarbonyloxy group, Examples thereof include a pentylcarbonyloxy group, a hexylcarbonyloxy group, an octylcarbonyloxy group, and a 2-ethylhexylcarbonyloxy group.

Examples of the ring formed by combining the combination of R ^b9 and R ^b10 include, for example, thiolane-1-ium ring (tetrahydrothiophenium ring), thian-1-ium ring, and 1,4-oxathian-4-ium. A ring etc. are mentioned.
^Examples of the ring formed by combining the combination of R ^b11 and R ^b12 include an oxocycloheptane ring, an oxocyclohexane ring, an oxonorbornane ring, and an oxoadamantane ring.

  Specific examples of the organic cation represented by the formulas (b2-1) to (b2-4) include those described in JP2010-204646A.

式（ｂ２−１−１）中、
Ｒ^b19〜Ｒ^b21は、それぞれ独立に、ハロゲン原子（より好ましくはフッ素原子）、ヒドロキシ基、炭素数１〜１８の脂肪族炭化水素基又は炭素数１〜１２のアルコキシ基を表し、該脂肪族炭化水素基は、ハロゲン原子、ヒドロキシ基、炭素数１〜１２のアルコキシ基、炭素数６〜１８の芳香族炭化水素基、炭素数２〜４のアシル基又はグリシジルオキシ基を有していてもよい。Ｒ^b19〜Ｒ^b21から選ばれる２つが一緒になってヘテロ原子を有してもよい環を形成してもよい。
ｖ２、ｗ２及びｘ２は、それぞれ独立に０〜５の整数（好ましくは０又は１）を表す。
ｖ２が２以上のとき、複数のＲ^b19〜Ｒ^b21はそれぞれ独立であり、ｗ２が２以上のとき、複数のＲ^b20は同一でも異なっていてもよく、ｘ２が２以上のとき、複数のＲ^b21は同一でも異なっていてもよい。 Among them, a cation (b2-1) is preferable, an organic cation represented by the following formula (b2-1-1) [hereinafter referred to as “cation (b2-1-1)”] is more preferable, and a triphenylsulfonium cation (In formula (b2-1-1), v2 = w2 = x2 = 0) or tolylsulfonium cation (in formula (b2-1-1), v2 = w2 = x2 = 1, R ¹⁹ , R ²⁰ and R ²¹ are all methyl groups).

In formula (b2-1-1),
R ^{b19 to} R ^b21 each independently represents a halogen atom (more preferably a fluorine atom), a hydroxy group, an aliphatic hydrocarbon group having 1 to 18 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms; The hydrocarbon group may have a halogen atom, a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, an acyl group having 2 to 4 carbon atoms, or a glycidyloxy group. Good. ^{Two members} selected from R ^b19 to R ^b21 may be combined to form a ring which may have a hetero atom.
v2, w2 and x2 each independently represent an integer of 0 to 5 (preferably 0 or 1).
When v2 is 2 or more, the plurality of R ^{b19 to} R ^b21 are independent from each other. When w2 is 2 or more, the plurality of R ^b20 may be the same or different. When x2 is 2 or more, a plurality of R ^{b19 b21} may be the same or different.

In the formula (b2-1-1), the aliphatic hydrocarbon group preferably has 1 to 12 carbon atoms, and the alkyl group having 1 to 12 carbon atoms and the alicyclic hydrocarbon group having 4 to 18 carbon atoms. Is more preferable.
R ^b19 , R ^b20 and R ^b21 are preferably each independently a halogen atom (more preferably a fluorine atom), a hydroxy group, an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. .

Examples of the cation (b2-1-1) include the following compounds.

Examples of the cation (b2-2) include the following.

Examples of the cation (b2-3) include the following.

  The acid generator (B1) is a combination of a sulfonate anion and an organic cation. As shown in Table 1, for example, the sulfonate anion and the organic cation can be arbitrarily combined. In Table 1, the sulfonate anion represented by the formula (b1-s-1) is represented as “(b1-s-1)” according to the formula number, and the formula (b2-c-1) Is represented as “(b2-c-1)” or the like according to the formula number.

  More preferred acid generators (B1) include salts represented by formulas (B1-1) to (B1-20), and more preferably formulas (B1-1) and formulas containing a triphenylsulfonium cation. Any of (B1-2), Formula (B1-3), Formula (B1-6), Formula (B1-11), Formula (B1-12), Formula (B1-13), and Formula (B1-14) The acid generator (B1) represented by these is mentioned.

<Basic compound (C)>
The basic compound (C) means a compound having a property of capturing an acid, particularly a compound having a property of capturing an acid generated from the acid generator (B) already described.

［式（Ｃ１）中、
Ｒ^c1〜Ｒ^c3は、それぞれ独立に、水素原子、炭素数１〜６のアルキル基、炭素数５〜１０の脂環式炭化水素基又は炭素数６〜１０の芳香族炭化水素基を表し、該アルキル基及び該脂環式炭化水素基に含まれる水素原子は、ヒドロキシ基、アミノ基又は炭素数１〜６のアルコキシ基で置換されていてもよく、該芳香族炭化水素基に含まれる水素原子は、炭素数１〜６のアルキル基、炭素数１〜６のアルコキシ基、炭素数５〜１０の脂環式炭化水素又は炭素数６〜１０の芳香族炭化水素基で置換されていてもよい。］ The basic compound (C) is preferably a basic nitrogen-containing organic compound, and examples thereof include amines and basic ammonium salts. As the amine, either an aliphatic amine or an aromatic amine may be used. Aliphatic amines include primary amines, secondary amines and tertiary amines. The basic compound (C) is preferably a compound represented by the formula (C1) to a compound represented by the formula (C8), more preferably a compound represented by the formula (C1-1). It is done.

[In the formula (C1),
R ^{c1 to} R ^c3 each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alicyclic hydrocarbon group having 5 to 10 carbon atoms, or an aromatic hydrocarbon group having 6 to 10 carbon atoms, The hydrogen atom contained in the alkyl group and the alicyclic hydrocarbon group may be substituted with a hydroxy group, an amino group or an alkoxy group having 1 to 6 carbon atoms, and hydrogen contained in the aromatic hydrocarbon group The atom may be substituted with an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alicyclic hydrocarbon having 5 to 10 carbon atoms, or an aromatic hydrocarbon group having 6 to 10 carbon atoms. Good. ]

［式（Ｃ１−１）中、
Ｒ^c2及びＲ^c3は、上記と同義である。
Ｒ^c4は、炭素数１〜６のアルキル基、炭素数１〜６のアルコキシ基、炭素数５〜１０の脂環式炭化水素又は炭素数６〜１０の芳香族炭化水素基を表す。
ｍ３は０〜３の整数を表し、ｍ３が２以上のとき、複数のＲ^c4は、同一でも異なっていてもよい。］

[In the formula (C1-1),
R ^c2 and R ^c3 are as defined above.
R ^c4 represents an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alicyclic hydrocarbon having 5 to 10 carbon atoms, or an aromatic hydrocarbon group having 6 to 10 carbon atoms.
m3 represents an integer of 0 to 3, and when m3 is 2 or more, the plurality of R ^c4 may be the same or different. ]

［式（Ｃ２）、式（Ｃ３）及び式（Ｃ４）中、
Ｒ^c5、Ｒ^c6、Ｒ^c7及びＲ^c8は、それぞれ独立に、Ｒ^c1と同じ意味を表す。
Ｒ^c9は、炭素数１〜６のアルキル基、炭素数３〜６の脂環式炭化水素基又は炭素数２〜６のアルカノイル基を表す。
ｎ４３は０〜８の整数を表し、ｎ４３が２以上のとき、複数のＲ^c9は、同一でも異なっていてもよい。］

[In Formula (C2), Formula (C3) and Formula (C4),
R ^c5 , R ^c6 , R ^c7 and R ^c8 each independently represent the same meaning as R ^c1 .
R ^c9 represents an alkyl group having 1 to 6 carbon atoms, an alicyclic hydrocarbon group having 3 to 6 carbon atoms, or an alkanoyl group having 2 to 6 carbon atoms.
n43 represents an integer of 0 to 8, and when n43 is 2 or more, the plurality of R ^c9 may be the same or different. ]

  Examples of the alkanoyl group include acetyl group, 2-methylacetyl group, 2,2-dimethylacetyl group, propionyl group, butyryl group, isobutyryl group, pentanoyl group, and 2,2-dimethylpropionyl group.

［式（Ｃ５）及び式（Ｃ６）中、
Ｒ^c10、Ｒ^c11、Ｒ^c12、Ｒ^c13及びＲ^c16は、それぞれ独立に、Ｒ^c1と同じ意味を表す。
Ｒ^c14、Ｒ^c15及びＲ^c17は、それぞれ独立に、Ｒ^c4と同じ意味を表す。
ｏ３及びｐ３は、それぞれ独立に０〜３の整数を表し、ｏ３が２以上であるとき、複数のＲ^c14は同一でも異なっていてもよく、ｐ３が２以上であるとき、複数のＲ^c15は同一でも異なっていてもよい。
Ｌ^c1は、炭素数１〜６のアルカンジイル基、−ＣＯ−、−Ｃ（＝ＮＨ）−、−Ｓ−又はこれらを組合せた２価の基を表す。］

[In Formula (C5) and Formula (C6),
R ^c10 , R ^c11 , R ^c12 , R ^c13 and R ^c16 each independently represent the same meaning as R ^c1 .
R ^c14 , R ^c15 and R ^c17 each independently represent the same meaning as R ^c4 .
o3 and p3 each independently represent an integer of 0 to 3. When o3 is 2 or more, the plurality of R ^c14 may be the same or different. When p3 is 2 or more, the plurality of R ^c15 is It may be the same or different.
L ^c1 represents an alkanediyl group having 1 to 6 carbon atoms, —CO—, —C (═NH) —, —S—, or a divalent group obtained by combining these. ]

［式（Ｃ７）及び式（Ｃ８）中、
Ｒ^c18、Ｒ^c19及びＲ^c20は、それぞれ独立に、Ｒ^c4と同じ意味を表す。
ｑ３、ｒ３及びｓ３は、それぞれ独立に０〜３の整数を表し、ｑ３が２以上であるとき、複数のＲ^c18は同一でも異なっていてもよく、ｒ３が２以上であるとき、複数のＲ^c19は同一でも異なっていてもよく、ｓ３が２以上であるとき、複数のＲ^c20は同一でも異なっていてもよい。
Ｌ^c2は、単結合又は炭素数１〜６のアルカンジイル基、−ＣＯ−、−Ｃ（＝ＮＨ）−、−Ｓ−又はこれらを組合せた２価の基を表す。］

[In Formula (C7) and Formula (C8),
R ^c18, R ^c19 and R ^c20 in each occurrence independently represent the same meaning as R ^c4.
q3, r3 and s3 each independently represents an integer of 0 to 3, and when q3 is 2 or more, a plurality of R ^c18 may be the same or different. When r3 is 2 or more, a plurality of Rc18 ^c19 may be the same or different, and when s3 is 2 or more, a plurality of ^Rc20 may be the same or different.
L ^c2 represents a single bond or an alkanediyl group having 1 to 6 carbon atoms, —CO—, —C (═NH) —, —S—, or a divalent group obtained by combining these. ]

Examples of the compound represented by the formula (C1) include 1-naphthylamine, 2-naphthylamine, aniline, diisopropylaniline, 2-, 3- or 4-methylaniline, 4-nitroaniline, N-methylaniline, N, N- Dimethylaniline, diphenylamine, hexylamine, heptylamine, octylamine, nonylamine, decylamine, dibutylamine, dipentylamine, dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, triethylamine, trimethylamine, tripropylamine, tributylamine, tri Pentylamine, trihexylamine, triheptylamine, trioctylamine, trinonylamine, tridecylamine, methyldibutylamine, methyldipentylamine, methyl Hexylamine, methyldicyclohexylamine, methyldiheptylamine, methyldioctylamine, methyldinonylamine, methyldidecylamine, ethyldibutylamine, ethyldipentylamine, ethyldihexylamine, ethyldiheptylamine, ethyldioctylamine, ethyldinonyl Amine, ethyldidecylamine, dicyclohexylmethylamine, tris [2- (2-methoxyethoxy) ethyl] amine, triisopropanolamine ethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4′-diamino-1,2-diphenyl Ethane, 4,4′-diamino-3,3′-dimethyldiphenylmethane, 4,4′-diamino-3,3′-diethyldiphenylmethane and the like,
Among these, diisopropylaniline is preferable, and 2,6-diisopropylaniline is particularly preferable.

Examples of the compound represented by the formula (C2) include piperazine.
Examples of the compound represented by the formula (C3) include morpholine.
Examples of the compound represented by the formula (C4) include piperidine and hindered amine compounds having a piperidine skeleton described in JP-A No. 11-52575.
Examples of the compound represented by the formula (C5) include 2,2′-methylenebisaniline.
Examples of the compound represented by the formula (C6) include imidazole and 4-methylimidazole.
Examples of the compound represented by the formula (C7) include pyridine and 4-methylpyridine.
Examples of the compound represented by the formula (C8) include 1,2-di (2-pyridyl) ethane, 1,2-di (4-pyridyl) ethane, 1,2-di (2-pyridyl) ethene, 1, 2-di (4-pyridyl) ethene, 1,3-di (4-pyridyl) propane, 1,2-di (4-pyridyloxy) ethane, di (2-pyridyl) ketone, 4,4′-dipyridyl sulfide 4,4′-dipyridyl disulfide, 2,2′-dipyridylamine, 2,2′-dipiconylamine, bipyridine and the like.

  As ammonium salts, tetramethylammonium hydroxide, tetraisopropylammonium hydroxide, tetrabutylammonium hydroxide, tetrahexylammonium hydroxide, tetraoctylammonium hydroxide, phenyltrimethylammonium hydroxide, 3- (trifluoromethyl) phenyltrimethyl Examples include ammonium hydroxide, tetra-n-butylammonium salicylate, and choline.

  Among these, diisopropylaniline is preferable, and 2,6-diisopropylaniline is particularly preferable.

<Solvent (D)>
The solvent (D) contained in the resist composition may be used on the substrate in the production of a resist pattern, which will be described later, according to the type and amount of the resin used and the type and amount of the acid generator (B). An optimal one can be appropriately selected from the viewpoint that the coating property when applying the resist composition is improved.

  Solvents (D) include glycol ether esters such as ethyl cellosolve acetate, methyl cellosolve acetate and propylene glycol monomethyl ether acetate; glycol ethers such as propylene glycol monomethyl ether; ethyl lactate, butyl acetate, amyl acetate and ethyl pyruvate Esters; ketones such as acetone, methyl isobutyl ketone, 2-heptanone and cyclohexanone; and cyclic esters such as γ-butyrolactone. Only 1 type may be used for a solvent (D) and it may use 2 or more types together.

<Other ingredients>
The resist composition may contain components other than the resin (A), the acid generator (B), the solvent (D), and the basic compound (C) used as necessary, as necessary. Good. This component is referred to as “component (F)”. Such component (F) is an additive widely used in the present technical field, such as a sensitizer, a dissolution inhibitor, a surfactant, a stabilizer, and a dye.

<Preparation of the present resist composition>
In the resist composition, the resin (A), the acid generator (B) and the solvent (D) are mixed, or the resin (A), the acid generator (B), the basic compound (C) and the solvent (D). Can be prepared by mixing. The component (F) may be mixed as necessary.
The mixing order is arbitrary and is not particularly limited. The temperature at the time of mixing can select an appropriate temperature range from the range of 10-40 degreeC according to the kind etc. of resin (A) to be used, the solubility with respect to solvents (D), such as resin (A).
An appropriate mixing time can be selected from 0.5 to 24 hours depending on the mixing temperature. The mixing means is not particularly limited, and stirring and mixing can be used.

  As described above, the content of the solvent (D) can be appropriately adjusted according to the type of the resin (A), but is preferably 90% by mass or more based on the total mass of the resist composition. In the present resist composition in which the content ratio of the solvent (D) is 90% by mass, the content ratio of the solid content with respect to the total mass of the present resist composition corresponds to 10% by mass. Here, the “solid content” refers to a material obtained by removing the solvent from the present resist composition. The solid content can be measured by a known analysis means such as liquid chromatography and gas chromatography.

The resist composition containing the solvent (D) in such a content ratio is suitable as a thin film resist capable of forming a composition layer having a thickness of about 30 to 300 nm, for example, in a resist pattern manufacturing method described later. From this viewpoint, the content ratio of the solvent (D) with respect to the total mass of the resist composition is more preferably 92% by mass or more, and still more preferably 94% by mass or more. The upper limit of the content rate of a solvent (D) is 99.9 mass% or less, for example, Preferably it is 99 mass% or less.
The content ratio of the solvent (D) can be controlled by the amount of the solvent (D) used in preparing the resist composition. After preparing the resist composition, the resist composition is subjected to, for example, liquid chromatography. It can also be obtained by using a known analysis means such as chromatography or gas chromatography.

  A preferable range of the content ratio of the resin (A) to the resist composition is selected from the total amount of the resin (A) with respect to the total mass of the solid content of the resist composition. For example, the resin content relative to the total mass of the solid content is preferably 80% by mass or more.

  A preferable range of the mass of the acid generator (B) is selected with respect to the total mass of the resin (A) contained in the resist composition. For example, the acid generator (B) is preferably 1 part by mass or more and more preferably 3 parts by mass or more with respect to 100 parts by mass of the resin (A). The acid generator (B) is preferably 40 parts by mass or less, more preferably 35 parts by mass or less, relative to 100 parts by mass of the resin (A).

  When using a basic compound (C) for this resist composition, it is preferable that the content rate of the basic compound (C) with respect to the total mass of solid content is about 0.01-1 mass%, for example.

  The suitable content of each of the resin (A), the acid generator (B) and the basic compound (C) used as necessary can be controlled by the amount of each used in preparing the resist composition. It is. After preparing the resist composition, the resist composition can be obtained by subjecting the resist composition to known analysis means such as gas chromatography and liquid chromatography.

  When component (F) is used in the present resist composition, an appropriate content can be adjusted depending on the type of component (F).

  After mixing the resin (A), the acid generator (B), the solvent (D), and the basic compound (C) or the component (F) used as necessary at a preferable content, the pore size is about 0.2 μm. This resist composition can be prepared by filtering using the above filter.

<Method for producing resist pattern>
Then, the manufacturing method of the resist pattern using this resist composition is demonstrated.
The method for producing a resist pattern of the present invention comprises:
(1) a step of applying the resist composition on a substrate;
(2) forming a composition layer on the substrate by removing the solvent from the resist composition applied on the substrate;
(3) a step of exposing the composition layer,
(4) A step of heating the composition layer after exposure,
(5) A step of developing the composition layer after heating is included.

  Application of the resist composition on the substrate in the step (1) can be performed by a coating apparatus widely used for applying a resist material for semiconductor microfabrication, such as a spin coater. In this way, a coating film made of a resist composition is formed on the substrate. The film thickness of the coating film can be adjusted by variously adjusting the conditions of the coating apparatus (coating conditions), and by performing appropriate preliminary experiments, the coating conditions can be adjusted so that the coating film has a desired film thickness. You can choose. Various substrates to be subjected to microfabrication can be selected as the substrate before applying the resist composition. Note that the substrate may be washed or an antireflection film may be formed before applying the resist composition. For the formation of the antireflection film, for example, a commercially available composition for organic antireflection film can be used.

In the step (2), the solvent (D) is removed from the coating film. Such solvent removal is performed by, for example, a heating unit using a heating device such as a hot plate, a decompression unit using a decompression unit, or a combination of these units. The conditions of the heating means and the decompression means are adjusted according to the type of the solvent (D) contained in the resist composition. For example, in the heating means (hot plate heating) using a hot plate, the surface temperature of the hot plate is set. What is necessary is just to set it as the range of about 50-200 degreeC. In the decompression means, after the substrate on which the coating film is formed is sealed in an appropriate decompressor, the internal pressure of the decompressor may be set to about 1 to 1.0 × 10 ⁵ Pa. In this way, a composition layer is formed on the substrate.

Step (3) is a step of exposing the composition layer, and preferably the composition layer can be exposed using an exposure machine. At this time, exposure is performed through a mask corresponding to a desired pattern to be finely processed. As an exposure light source of the exposure machine, an ultraviolet light emitting device such as a KrF excimer laser (wavelength 248 nm), an ArF excimer laser (wavelength 193 nm), an F ₂ laser (wavelength 157 nm), a solid laser light source (YAG Various lasers such as those that emit laser light from a far ultraviolet region or a vacuum ultraviolet region by converting the wavelength of laser light from a semiconductor laser or the like can be used. The exposure machine may be an immersion exposure machine.

  As described above, by exposing through a mask, an exposed portion (exposed portion) and an unexposed portion (unexposed portion) are generated in the composition layer. In the composition layer of the exposed portion, the acid generator (B) contained in the composition layer generates an acid upon receiving exposure energy, and further, an acid labile group in the resin (A) is generated by the action with the generated acid. Causes a deprotection reaction, and as a result, the resin (A) in the composition layer of the exposed portion becomes soluble in an alkaline aqueous solution. On the other hand, since the exposure energy is not received in the unexposed area, the resin (A) remains insoluble or hardly soluble in the alkaline aqueous solution. Thus, the solubility with respect to aqueous alkali solution differs remarkably between the composition layer in an exposed part, and the composition layer in an unexposed part.

  In the step (4), a heat treatment is performed in order to promote a deprotecting group reaction that may occur in the exposed portion and / or its progress. For the heat treatment, a heating means using a hot plate shown in the step (2) is employed. In the hot plate heating in the step (4), the surface temperature of the hot plate is preferably about 50 to 200 ° C, more preferably about 70 to 150 ° C.

Step (5) is a step of developing the heated composition layer, and preferably the heated composition layer is developed with a developing device. In this development, the composition layer after heating is brought into contact with an alkaline aqueous solution to dissolve the composition layer in the exposed portion in the alkaline aqueous solution, leaving the composition layer in the unexposed portion on the substrate. Thereby, a resist pattern is manufactured on the substrate.
The alkaline aqueous solution used here is referred to as “alkaline developer”, and those used in this technical field can be used. Examples of the alkaline aqueous solution include an aqueous solution of tetramethylammonium hydroxide and an aqueous solution of (2-hydroxyethyl) trimethylammonium hydroxide (commonly called choline).

  The obtained resist pattern is preferably rinsed with ultrapure water or the like to further remove moisture remaining on the substrate and the resist pattern.

  According to the resist pattern manufacturing method including the steps (1) to (5) as described above, this resist composition can manufacture a resist pattern with an excellent focus margin (DOF). In addition, steps (1) to (5) are included by adjusting the content of each of the resin (A), acid generator (B) and basic compound (C) contained in the resist composition. The resist pattern manufacturing method also has an effect that an excellent line edge roughness (LER) resist pattern can be obtained.

<Application>
The resist composition of the present invention comprises a resist composition for KrF excimer laser exposure, a resist composition for ArF excimer laser exposure, a resist composition for EB or a resist composition for EUV exposure machines, and further for immersion exposure. It is suitable as a resist composition.

Hereinafter, the present invention will be described more specifically with reference to examples. In the examples, “%” and “parts” representing the content or amount used are based on mass unless otherwise specified. The composition ratio of the resin (A) (copolymerization ratio of the structural unit derived from each monomer used for the production of the resin (A) to the resin (A)) is the amount of unreacted monomer in the reaction liquid after the polymerization is finished. It measured using the chromatography, and computed by calculating | requiring the monomer amount used for superposition | polymerization from the obtained result. The weight average molecular weight of the resin (A) is a value determined by gel permeation chromatography.
The analysis conditions of gel permeation chromatography are as follows.
Column: TSKgel Multipore HXL-M x 3 + guardcolumn (manufactured by Tosoh Corporation)
Eluent: Tetrahydrofuran Flow rate: 1.0 mL / min
Detector: RI detector Column temperature: 40 ° C
Injection volume: 100 μl
Molecular weight standard: Standard polystyrene (manufactured by Tosoh Corporation)

  The structure of the compound was confirmed by measuring the molecular peak using mass spectrometry (LC is model 1100 manufactured by Agilent, and MASS is LC / MSD manufactured by Agilent).

式（Ｉ１−１）で表される化合物７．００部及びアセトニトリル３５．００部を、反応器中に仕込み、２３℃で３０分間攪拌し、４０℃程度に昇温した。得られた溶液に、式（Ｉ１−２）で表される化合物７．０２部を添加し、１−クロロブタン１４０部および触媒としてチタニウムイソプロポキシド０．６部を、７０℃程度まで昇温し、さらに、２時間攪拌した。得られた反応液を冷却、ろ過し、ろ液を回収することにより、式（Ｉ１−３）で表される化合物を含む溶液を得た。式（Ｉ１−３）で表される化合物を含む溶液に、式（Ｉ１−４）で表される化合物５．０６部を添加し、２３℃で２４時間攪拌した。得られた反応混合物を濃縮した。得られた濃縮物をカラム分取（固定床：メルク製シリカゲル６０−２００メッシュ、展開溶媒：ｎ−ヘプタン／酢酸エチル＝５／１）することにより、式（Ｍ−Ｄ）で表される化合物５．９８部を得た。
ＭＳ（質量分析）：２７４．１（分子イオンピーク） Synthesis example 1
[Synthesis of Compound Represented by Formula (MD); Examples for Production of Compound (am ′)]

7.00 parts of the compound represented by the formula (I1-1) and 35.00 parts of acetonitrile were charged into a reactor, stirred at 23 ° C. for 30 minutes, and heated to about 40 ° C. 7.02 parts of a compound represented by the formula (I1-2) is added to the obtained solution, and 140 parts of 1-chlorobutane and 0.6 parts of titanium isopropoxide as a catalyst are heated to about 70 ° C. The mixture was further stirred for 2 hours. The obtained reaction liquid was cooled and filtered, and the filtrate was recovered to obtain a solution containing the compound represented by the formula (I1-3). To the solution containing the compound represented by the formula (I1-3), 5.06 parts of the compound represented by the formula (I1-4) was added and stirred at 23 ° C. for 24 hours. The resulting reaction mixture was concentrated. The resulting concentrate is subjected to column fractionation (fixed bed: Merck silica gel 60-200 mesh, developing solvent: n-heptane / ethyl acetate = 5/1), whereby the compound represented by the formula (MD) 5.98 parts were obtained.
MS (mass spectrometry): 274.1 (molecular ion peak)

以下、ここに示す樹脂合成用の化合物を、その式符号に応じて「モノマー（ａ１−１−２）」などという。 Resin Synthesis The compounds used for resin synthesis are shown below.

Hereinafter, the compound for resin synthesis shown here is referred to as “monomer (a1-1-2)” or the like according to the formula code.

Synthesis Example 2 [Synthesis of Resin A1]
Using monomer (a1-1-2), monomer (a2-1-1), monomer (a3-1-1) and monomer (MD), the molar ratio (monomer (a1-1-2): monomer (A2-1-1): monomer (a3-1-1): monomer (MD)) was mixed so that the ratio was 40: 20: 30: 10, and the dioxane was 1.5 mass times the total monomer amount. To make a solution. To this solution, 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added to the total monomer amount, respectively, and these were heated at 73 ° C. for about 5 hours. did. The obtained reaction mixture was poured into a large amount of methanol / water mixed solvent to precipitate the resin, and this resin was filtered. The obtained resin was dissolved again in dioxane to obtain a solution, and this solution was poured into a methanol / water mixed solvent to precipitate the resin, followed by reprecipitation operation of filtering the resin twice, and the weight average. Resin A1 (copolymer) having a molecular weight of 9.5 × 10 ³ was obtained in a yield of 85%. This resin A1 has the following structural units.

Synthesis Example 3 [Synthesis of Resin A2]
Monomer (MA), monomer (MB), and monomer (MC) were used, and the molar ratio (monomer (MA): monomer (MB): monomer (MC)) was 39. 4: 30.3: 30.3 The mixture was mixed and 1.5 mass times MIK (4-methyl-2-pentanone) of the total monomer amount was added to obtain a solution. To this solution, 1 mol% and 3 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added to the total monomer amount, respectively, and these were heated at 80 ° C. for about 8 hours. did. The obtained reaction mixture was poured into a large amount of methanol / water mixed solvent to precipitate the resin, and this resin was filtered.
The resin thus obtained is dissolved again in methanol, and the resulting solution is poured into a methanol / water mixed solvent to precipitate the resin, followed by two reprecipitation operations of filtering the resin, and a weight average molecular weight of 9. 2 × 10 ³ resin A2 (copolymer) was obtained with a yield of 70%.
This resin A2 has the following structural units.

Synthesis Example 4 [Synthesis of Resin A3]
As the monomer, the monomer (a1-1-2), the monomer (a2-1-1), the monomer (a3-1-1) and the monomer (ME) are used, and the molar ratio (monomer (a1-1-2) ): Monomer (a2-1-1): Monomer (a3-1-1): Monomer (ME)) is mixed so as to be 30: 20: 40: 10, and 1.5 mass of the total monomer amount. Double dioxane was added to make a solution. To this solution, azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added in an amount of 0.8 mol% and 2.4 mol%, respectively, based on the total monomer amount, and these were added at 75 ° C. Heated for about 5 hours. The obtained reaction mixture was poured into a large amount of methanol / water mixed solvent to precipitate the resin, and this resin was filtered. The obtained resin was again dissolved in dioxane, and the resulting solution was poured into a methanol / water mixed solvent to precipitate the resin, followed by two reprecipitation operations of filtering the resin, and a weight average molecular weight of 1.1. × 10 ⁴ of the resin A3 (copolymer) was obtained in 66% yield. This resin A3 has the following structural units.

Synthesis Example 5 [Synthesis of Resin X1]
Monomer (H) was used as a monomer, and 1.5 mass times dioxane of the total monomer amount was added to prepare a solution. To this solution, 0.7 mol% and 2.1 mol% of azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile), respectively, as initiators were added with respect to the total monomer amount, and these were added at 75 ° C. Heated for about 5 hours. The obtained reaction mixture was poured into a large amount of methanol / water mixed solvent to precipitate the resin, and this resin was filtered. The obtained resin was again dissolved in dioxane, and the resulting solution was poured into a methanol / water mixed solvent to precipitate the resin, followed by two reprecipitation operations of filtering the resin, and a weight average molecular weight of 1.8. A × 10 ⁴ resin X1 (copolymer) was obtained in a yield of 77%. This resin X1 has the following structural units.

Examples and Comparative Examples <Preparation of Resist Composition>
The components shown in Table 2 were mixed and dissolved in the following solvents, and further filtered through a fluororesin filter having a pore size of 0.2 μm to prepare a resist composition.

<Resin>
A1 and A2: Resin A1 and Resin A2 obtained in the above-described resin synthesis example
<Acid generator>

<Basic compound: Quencher>
C1: 2,6-Diisopropylaniline <Solvent>
Propylene glycol monomethyl ether acetate 268.0 parts Propylene glycol monomethyl ether 20.0 parts 2-heptanone 20.0 parts γ-butyrolactone 3.0 parts

<Immersion exposure evaluation of resist composition>
An organic antireflective coating composition [ARC-29; manufactured by Nissan Chemical Industries, Ltd.] was applied onto a 12-inch silicon wafer and baked at 205 ° C. for 50 seconds to obtain a thickness of 78 nm. An organic antireflection film was formed. Next, the above resist composition was spin-coated on the organic antireflection film so that the film thickness after drying was 110 nm. The obtained silicon wafer was pre-baked (PB) for 50 seconds on a direct hot plate at the temperature described in the “PB” column of Table 2.
Using the ArF excimer stepper for immersion exposure [XT: 1900 Gi; manufactured by ASML, NA = 1.30, 35 Y-axis polarized light], the exposure amount was changed stepwise for the obtained wafer. Was subjected to immersion exposure.
After the exposure, post-exposure baking (PEB) was performed for 50 seconds on the hot plate at the temperature described in the “PEB” column of Table 2, and further with a 2.38 mass% tetramethylammonium hydroxide aqueous solution for 60 seconds. Paddle development was performed.

  In each resist film, the exposure amount at which the 45 nm line and space pattern becomes an exposure amount of 1: 1 was defined as the effective sensitivity.

<Focus margin (DOF) evaluation>
Focus margin (DOF): When the focus is moved in the effective sensitivity, a range (42.75 to 47.25 nm) in which the line width is 45 nm ± 5% is used as the line width index. The results of DOF are shown in Table 3.

  This resist composition (Examples 1 and 2) was able to produce a resist pattern with an excellent focus margin (DOF). On the other hand, in the resist composition of Comparative Example 1, the focus margin (DOF) at the time of producing the resist pattern was poor.

<Immersion exposure evaluation of resist composition>
An organic antireflective coating composition [ARC-29; manufactured by Nissan Chemical Industries, Ltd.] was applied onto a 12-inch silicon wafer and baked at 205 ° C. for 60 seconds to obtain a thickness of 78 nm. An organic antireflection film was formed. Next, the above resist composition was spin-coated on the organic antireflection film so that the film thickness after drying was 85 nm. The obtained silicon wafer was pre-baked (PB) for 60 seconds on a direct hot plate at the temperature described in the “PB” column of Table 2.
Using the ArF excimer stepper for immersion exposure [XT: 1900 Gi; manufactured by ASML, NA = 1.35, 3/4 Annular XY polarized light], the exposure amount was changed stepwise on the obtained wafer. The andspace pattern was subjected to immersion exposure.
After the exposure, post exposure bake (PEB) is performed on the hot plate at the temperature described in the “PEB” column of Table 2 for 60 seconds, and further with a 2.38 mass% tetramethylammonium hydroxide aqueous solution for 60 seconds. Paddle development was performed.

  In each resist film, the exposure amount at which the 50 nm line and space pattern becomes an exposure amount of 1: 1 was defined as the effective sensitivity.

<Line edge roughness evaluation (LER)>
The wall surface of the resist pattern after the lithography process was observed with a scanning electron microscope, and the unevenness fluctuation width on the side wall of the resist pattern was determined. The results are shown in Table 4.

  The resist composition of the present invention is useful for fine processing of semiconductors and has high industrial utility value.

Claims (9)

A resist composition containing the following (A), (B) and (D).
(A) A resin having a structural unit represented by the formula (a).

[In the formula (a),
R ¹ represents a C 1-6 alkyl group, a hydrogen atom or a halogen atom which may have a halogen atom.
R ² represents an optionally substituted aliphatic hydrocarbon group having 1 to 6 carbon atoms, a single bond, or a group represented by the formula (a-1).

(In the formula (a-1),
s represents 0 or 1.
A ¹⁰ and A ¹¹ each independently represent a C 1-5 aliphatic hydrocarbon group which may have a substituent.
A ¹² represents an aliphatic hydrocarbon group having 1 to 5 carbon atoms which may have a substituent or a single bond.
X ¹⁰ and X ¹¹ each independently represent an oxygen atom, a carbonyl group, a carbonyloxy group or an oxycarbonyl group. )
R ³ represents a sulfolane ring group represented by the formula (b).

(In the formula (b),
n represents an integer of 0 to 7.
R represents a hydroxy group, an alkoxy group, or an aliphatic hydrocarbon group having 1 to 18 carbon atoms, and when n is 2 or more, a plurality of R may be the same or different and are each bonded to adjacent carbon atoms. Two Rs may combine to form a ring together with the carbon atom.
--- represents a single bond or a double bond.
* Is a bond with R ² . ]]
(B) Acid generator represented by formula (B1)

[In the formula (B1),
Q ¹ and Q ² each independently represents a fluorine atom or a C 1-6 perfluoroalkyl group.
L ^b1 represents a divalent saturated hydrocarbon group having 1 to 17 carbon atoms, and the methylene group constituting the saturated hydrocarbon group may be replaced with an oxygen atom or a carbonyl group.
Y represents an optionally substituted aliphatic hydrocarbon group having 1 to 18 carbon atoms, and the methylene group constituting the aliphatic hydrocarbon group is replaced with an oxygen atom, a sulfonyl group or a carbonyl group. May be.
Z ⁺ represents an organic cation. ]
(D) Solvent Said (A) is
R ^{2 in the} formula (a) is a single bond, —CH ₂ —CO—O— * or —CH ₂ —CH ₂ —O—CO— * (* is a bond to R ³ ). The resist composition according to claim 1, which is a resin. Said (A) is
The resist composition according to claim 1, wherein R ^{3 in the} formula (a) is a resin having a sulfolane ring group selected from the group consisting of the formulas (b-1) to (b-5).

[In formula (b-1) to formula (b-5), * represents a bond to R ² . ]   The resist composition according to any one of claims 1 to 3, wherein (A) is a resin that is insoluble or hardly soluble in an aqueous alkali solution and is soluble in an aqueous alkali solution by the action of an acid. Said (A) is
The resist composition according to claim 4, which is a resin having a structural unit represented by formula (a1-1) or formula (a1-2).

[In Formula (a1-1) and Formula (a1-2),
L ^a1 and L ^a2 each independently represent an oxygen atom or ^* —O— (CH ₂ ) _k1 —CO—O— (k1 represents an integer of 1 to 7, and * represents a bond to —CO—. .).
R ^a4 and R ^a5 each independently represent a hydrogen atom or a methyl group.
R ^a6 and R ^a7 each independently represent an alkyl group having 1 to 8 carbon atoms or an alicyclic hydrocarbon group having 3 to 10 carbon atoms.
m1 represents the integer of 0-14.
n1 represents an integer of 0 to 10.
n2 represents an integer of 0 to 3. ] Furthermore, the resist composition in any one of Claims 1-5 containing a basic compound.
(1) The process of apply | coating the resist composition in any one of Claims 1-6 on a board | substrate,
(2) a step of removing the solvent from the composition after coating to form a composition layer;
(3) a step of exposing the composition layer,
(4) A step of heating the composition layer after exposure,
(5) a step of developing the composition layer after heating;
A method for producing a resist pattern including: A compound represented by the formula (am ′).

[In the formula (am ′),
R ¹ represents a C 1-6 alkyl group, a hydrogen atom or a halogen atom which may have a halogen atom.
R ^2x represents a C 1-6 aliphatic hydrocarbon group which may have a substituent or a group represented by the formula (a-1).

(In the formula (a-1),
s represents 0 or 1.
A ¹⁰ and A ¹¹ each independently represent a C 1-5 aliphatic hydrocarbon group which may have a substituent.
A ¹² represents an aliphatic hydrocarbon group having 1 to 5 carbon atoms which may have a substituent or a single bond.
X ¹⁰ and X ¹¹ each independently represent an oxygen atom, a carbonyl group, a carbonyloxy group or an oxycarbonyl group. )
R ³ represents a sulfolane ring group represented by the formula (b).

(In the formula (b),
n represents an integer of 0 to 7.
R represents a hydroxy group, an alkoxy group, or an aliphatic hydrocarbon group having 1 to 18 carbon atoms, and when n is 2 or more, a plurality of R may be the same or different and are each bonded to adjacent carbon atoms. Two Rs may combine to form a ring together with the carbon atom.
--- represents a single bond or a double bond.
* Is a bond with R ² . ]]   A resin having a structural unit derived from the compound according to claim 8.