JP6246492B2 - Resist composition and method for producing resist pattern - Google Patents

Description

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

Patent Document 1 describes a resist composition containing, as a resin, a resin composed of a structural unit represented by the formula (u-A) and a structural unit represented by the formula (u-C).

Patent Document 2 discloses a resin composed of a structural unit represented by the formula (u-L) and a structural unit represented by the formula (u-A) as a resin, and a structure represented by the formula (u-A). A resist composition containing a unit, a structural unit represented by the formula (u-H), and a resin composed of the structural unit represented by the formula (u-B) is described.
Further, it is known that when a resist pattern is formed from a resist composition by photolithography, a positive resist pattern is obtained when developed with an alkaline developer, and a negative resist pattern is obtained when developed with an organic solvent ( Non-patent document 1).

JP 2000-122294 A JP 2010-197413 A

Published by Techno Times Inc. Monthly Display '11 June p. 31

  The objective of this invention is providing the resist composition which can manufacture the resist pattern which is the outstanding line edge roughness (LER).

The present invention includes the following inventions.
[1] (A1) a resin having a structural unit represented by formula (I),
(A2) a resin comprising a structural unit represented by formula (II) and a structural unit having an acid labile group, and
(B) A resist composition containing an acid generator.
[In the formula (I),
R ¹ represents a hydrogen atom or a methyl group.
A ¹ represents an alkanediyl group having 1 to 6 carbon atoms.
A ¹³ represents a divalent aliphatic hydrocarbon group having 1 to 18 carbon atoms which may have a halogen atom.
X ¹² represents * —CO—O— or * —O—CO—, and * represents a bond to A ¹³ .
A ¹⁴ represents an aliphatic hydrocarbon group having 1 to 17 carbon atoms which may have a halogen atom. ]
[In the formula (II),
R ²¹ represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom.
A ²¹ represents a single ^{bond, * -A 22 -O-, * -A} 22 -CO-O-, * -A 22 -CO-O-A 23 -CO-O- or ^* -A ²² -O-CO -A ²³ represent a -O-.
* Represents a bond with -O-.
A ²² and A ²³ each independently represents an alkanediyl group having 1 to 6 carbon atoms. ]
[2] The resist composition according to [1], wherein A ¹³ is a C 1-6 perfluoroalkanediyl group.
[3] The resist composition according to [1] or [2], further containing a solvent.
[4] (1) A step of applying the resist composition according to any one of [1] to [3] on a substrate,
(2) The process of drying the composition after application | coating and forming a composition layer,
(3) a step of exposing the composition layer,
(4) A method for producing a resist pattern, comprising: a step of heating the composition layer after exposure; and (5) a step of developing the composition layer after heating.

  According to the resist composition of the present invention, a resist pattern with good line edge roughness and few defects can be produced.

In the present specification, "(meth) acrylic monomer" means at least one monomer having a "CH ₂ = CH-CO-" or _{"CH 2 = C (CH 3)} -CO- " structure of To do. 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.

<Resist composition>
The resist composition of the present invention comprises:
(A) resin (hereinafter sometimes referred to as “resin (A)”), and
(B) An acid generator (hereinafter may be referred to as “acid generator (B)”).
It is preferable that the resist composition of the present invention further contains a solvent (E).
The resist composition of the present invention preferably further contains a basic compound (C).

<Resin (A)>
The resin (A) contained in the resist composition of the present invention is
(A1) a resin having a structural unit represented by formula (I) and (A2) a resin comprising a structural unit represented by formula (II) and a structural unit having an acid labile group.
In the present specification, the “acid labile group” is a group having a leaving group and forming a hydrophilic group (for example, a hydroxy group or a carboxy group) by leaving the leaving group by contact with an acid. Means.
Moreover, resin (A) may contain resin other than resin (A1) and (A2) which are mentioned later.

<Resin (A1)>
The resin (A1) has a structural unit represented by the formula (I) (hereinafter sometimes referred to as “structural unit (I)”).
[In the formula (I),
R ¹ represents a hydrogen atom or a methyl group.
A ¹ represents an alkanediyl group having 1 to 6 carbon atoms.
A ¹³ represents an aliphatic hydrocarbon group having 1 to 18 carbon atoms which may have a halogen atom.
X ¹² represents * —CO—O— or * —O—CO—, and * represents a bond to A ¹³ .
A ¹⁴ represents an aliphatic hydrocarbon group having 1 to 17 carbon atoms which may have a halogen atom. ]

In the formula (I), as the alkanediyl group of A ¹ , methylene group, ethylene group, propane-1,3-diyl group, propane-1,2-diyl group, butane-1,4-diyl group, pentane- Linear alkanediyl groups such as 1,5-diyl group and hexane-1,6-diyl group; 1-methylpropane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2- Examples thereof include branched alkanediyl groups such as methylpropane-1,2-diyl group, 1-methylbutane-1,4-diyl group, and 2-methylbutane-1,4-diyl group.

Examples of the halogen atom for A ¹³ include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Of these, a fluorine atom is preferred.
The aliphatic hydrocarbon group for A ¹³ includes either a chain or a cyclic group, and a divalent aliphatic hydrocarbon group in which these are combined. The aliphatic hydrocarbon may have a carbon-carbon unsaturated bond, but is preferably a saturated aliphatic hydrocarbon group.
The aliphatic hydrocarbon group which may have a halogen atom for A ¹³ is preferably a saturated aliphatic hydrocarbon group which may have a fluorine atom.
Examples of the divalent aliphatic hydrocarbon group that may have a chain halogen atom (preferably a fluorine atom) include a methylene group, a difluoromethylene group, an ethylene group, a perfluoroethylene group, a propanediyl group, and a perfluoropropanediyl group. Group, butanediyl group, perfluorobutanediyl group, pentanediyl group, perfluoropentanediyl group, dichloromethylene group and dibromomethylene group.
The divalent aliphatic hydrocarbon group which may have a cyclic halogen atom (preferably a fluorine atom) may be monocyclic or polycyclic. Examples of the monocyclic aliphatic hydrocarbon group include a cyclohexanediyl group, a perfluorocyclohexanediyl group, and a perchlorocyclohexanediyl group. Examples of the polycyclic divalent aliphatic hydrocarbon group include an adamantanediyl group, a norbornanediyl group, and a perfluoroadamantanediyl group.

The aliphatic hydrocarbon group for A ¹⁴ includes either a chain or a cyclic group, and an aliphatic hydrocarbon group in which these are combined. The aliphatic hydrocarbon may have a carbon-carbon unsaturated bond, but is preferably a saturated aliphatic hydrocarbon group.
The aliphatic hydrocarbon group which may have a halogen atom for A ¹⁴ is preferably a saturated aliphatic hydrocarbon group which may have a fluorine atom.
Examples of the aliphatic hydrocarbon group which may have a chain halogen atom (preferably a fluorine atom) include trifluoromethyl group, difluoromethyl group, methyl group, perfluoroethyl group, 1,1,1-trifluoro Ethyl group, 1,1,2,2-tetrafluoroethyl group, ethyl group, perfluoropropyl group, 1,1,1,2,2-pentafluoropropyl group, propyl group, perfluorobutyl group, 1,1,2 2,3,3,4,4-octafluorobutyl group, butyl group, perfluoropentyl group, 1,1,1,2,2,3,4,4-nonafluoropentyl group and pentyl group, hexyl Group, perfluorohexyl group, heptyl group, perfluoroheptyl group, octyl group, perfluorooctyl group, trichloromethyl group and tribromomethyl group, etc. It is below.
The aliphatic hydrocarbon group which may have a cyclic halogen atom (preferably a fluorine atom) may be monocyclic or polycyclic. Examples of the group containing a monocyclic aliphatic hydrocarbon group include a cyclopropylmethyl group, a cyclopropyl group, a cyclobutylmethyl group, a cyclopentyl group, a cyclohexyl group, a perfluorocyclohexyl group, and a perchlorocyclohexyl group. Examples of the group containing a polycyclic aliphatic hydrocarbon group include an adamantyl group, an adamantylmethyl group, a norbornyl group, a norbornylmethyl group, a perfluoroadamantyl group, and a perfluoroadamantylmethyl group.

In the formula (I), A ¹ is preferably an ethylene group.
The aliphatic hydrocarbon group for A ¹³ preferably has 1 to 6 carbon atoms, and more preferably 2 to 3 carbon atoms.
The aliphatic hydrocarbon group for A ¹⁴ preferably has 3 to 12 carbon atoms, and more preferably 3 to 10 carbon atoms. Among them, A ¹⁴ is preferably a group containing an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and more preferably a cyclopropylmethyl group, a cyclopentyl group, a cyclohexyl group, a norbornyl group, and an adamantyl group.

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

In the above structural unit, a structural unit in which the methyl group corresponding to R ¹ is replaced by a hydrogen atom can also be given as a specific example of the structural unit (I).

The structural unit (I) is derived from a compound represented by the formula (I ′) (hereinafter sometimes referred to as “compound (I ′)”).
[In Formula (I ′), R ¹ , A ¹³ , X ¹² and A ¹⁴ represent the same meaning as described above. ]

The compound represented by the formula (I ′) can be produced, for example, by reacting the compound represented by the formula (Is-1) with the carboxylic acid represented by the formula (Is-2). .
This reaction is usually performed in the presence of a solvent. As the solvent, tetrahydrofuran, toluene and the like are used. In addition, you may coexist a well-known esterification catalyst (for example, an acid catalyst, a carbodiimide catalyst, etc.) in the case of reaction.
The compound represented by the formula (Is-1) may be a commercially available product or a product produced by a known method. Here, the known method includes, for example, a method of condensing (meth) acrylic acid or a derivative thereof (for example, (meth) acrylic acid chloride etc.) and an appropriate diol (HO-A ¹ -OH). It is done. Examples of commercially available products include hydroxyethyl methacrylate.
The carboxylic acid represented by the formula (Is-2) can be produced by a known method. Examples of the carboxylic acid represented by the formula (Is-2) include the following compounds. Moreover, it can also be used as a carboxylic acid amine salt.

The resin (A1) may have a structural unit different from the structural unit (I).
As the structural unit different from the structural unit (I), a structural unit derived from an acid labile monomer (a1) described later, a structural unit derived from an acid stable monomer described later, a structural unit represented by the formula (IIIA), Examples include structural units derived from known monomers used in the field, structural units represented by the formula (II) described below, and the like. A structural unit represented by the formula (IIIA) is preferable.

[In the formula (IIIA),
R ¹¹ represents a hydrogen atom or a methyl group.
Ring W ² represents a hydrocarbon ring having 6 to 10 carbon atoms.
A ¹² represents —O—, ^* —CO—O—, or ^* —O—CO— ( ^* represents a bond to ring W ¹ ).
R ¹² represents a C 1-6 alkyl group having a fluorine atom. ]

Examples of the hydrocarbon ring of ring W ² include an alicyclic hydrocarbon ring, and a saturated alicyclic hydrocarbon ring is preferable.
Examples of the saturated alicyclic hydrocarbon ring include the following rings.

As the ring W ² , for example, an adamantane ring or a cyclohexane ring is preferable, and an adamantane ring is more preferable.
As a C1-C6 alkyl group which has a fluorine atom of R < ¹² >, the fluorinated alkyl group mentioned above and the following group are mentioned, for example.

As the structural unit represented by the formula (IIIA), for example, the structural unit represented by the following is preferable.
In the above structural unit, a structural unit in which a methyl group corresponding to R ¹¹ is replaced with a hydrogen atom can also be given as a specific example of the structural unit (IIIA).
Among these, a structural unit represented by the formula (IIIA-1) or a structural unit in which a methyl group corresponding to R ¹¹ is replaced with a hydrogen atom is particularly preferable.

The content ratio of the structural unit (I) in the resin (A1) is preferably in the range of 5 to 100 mol%, more preferably in the range of 10 to 100 mol%, based on all the structural units of the resin (A1). The range of ˜100 mol% is further preferred, the range of 80˜100 mol% is particularly preferred, and it is particularly preferred that only substantially the structural unit (I) is present. When the content ratio of the structural unit (I) is within the above range, a resist pattern with excellent line edge roughness (LER) can be produced, and in particular, a resist pattern with few defects can be produced.
When the resin (A1) has the structural unit (IIIA), the content ratio of the structural unit (IIIA) in the resin (A1) is in the range of 1 to 95 mol% with respect to all the structural units of the resin (A1). The range of 2 to 80 mol% is more preferable, the range of 5 to 70 mol% is more preferable, the range of 5 to 50 mol% is particularly preferable, and the range of 5 to 30 mol% is particularly preferable.
Resin (A1) having structural units (I) and / or (IIIA) in such a content ratio is compound (I ′), structural unit (IIIA) relative to the total molar amount of all monomers used in the production of resin (A1). It can be produced by adjusting the molar amount of the monomer used for deriving.
Each structural unit (I) and / or (IIIA) constituting the resin (A1) may be one kind or a combination of two or more kinds, and optionally, an acid stable monomer (a1), an acid stable monomer, which will be described later, It can be produced by a known polymerization method (for example, radical polymerization method) by combining one or more monomers known in the art.
The weight average molecular weight of the resin (A1) is preferably 5,000 or more (more preferably 7,000 or more, more preferably 10,000 or more), 80,000 or less (more preferably 50,000 or less, further preferably Is 30,000 or less). A weight average molecular weight 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 specification.

<Resin (A2)>
The resin (A2) has a structural unit represented by the formula (II) (hereinafter sometimes referred to as “structural unit (II)”) and a structural unit having an acid labile group.

<Structural unit (II)>
[In the formula (II),
R ²¹ represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom.
A ²¹ represents a single ^{bond, * -A 22 -O-, * -A} 22 -CO-O-, * -A 22 -CO-O-A 23 -CO-O- or ^* -A ²² -O-CO -A ²³ represent a -O-.
* Represents a bond with -O-.
A ²² and A ²³ each independently represents an alkanediyl group having 1 to 6 carbon atoms. ]

Examples of the halogen atom for R ²¹ in formula (II) include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.
Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, and n-hexyl group. It is a C1-C4 alkyl group, More preferably, it is a methyl group or an ethyl group.
Examples of the alkyl group having a halogen atom include trifluoromethyl group, perfluoroethyl group, perfluoropropyl group, perfluoroisopropyl group, perfluorobutyl group, perfluorosec-butyl group, perfluorotert-butyl group, perfluoropentyl group, perfluorohexyl group, A trichloromethyl group, a tribromomethyl group, a triiodomethyl group, etc. are mentioned.
R ²¹ is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and more preferably a hydrogen atom, a methyl group or an ethyl group.

Examples of the alkanediyl group of A ²² and A ²³ include a methylene group, an ethylene group, a propane-1,3-diyl group, a propane-1,2-diyl group, a butane-1,4-diyl group, and a pentane-1,5. -Diyl group and hexane-1,6-diyl group, butane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1, Examples include 4-diyl group and 2-methylbutane-1,4-diyl group.
A ²¹ is preferably a single bond or ^* —A ²² —CO—O—, and more preferably a single bond, —CH ₂ —CO—O— or —C ₂ H ₄ —CO—O—. .

As structural unit (II), the following are mentioned, for example.

Regarding the structural units represented by formula (aa-1) to formula (aa-6), structural units in which the methyl group corresponding to R ²¹ is replaced with a hydrogen atom are also given as specific examples of structural unit (II). Can do.

The structural unit (II) is derived from a compound represented by the formula (II ′) (hereinafter sometimes referred to as “compound (I ′)”).
[In formula (II ′), R ²¹ and A ²¹ represent the same meaning as described above. ]

In the compound (II ′), A ²¹ is * —CH ₂ —CO—O— (* represents a bond to —CO—O—), and the compound represented by the formula (II′-1) is The compound represented by the formula (II′-1-a) and the compound represented by the formula (II′-1-b) can be obtained by reacting in a solvent. Here, methylene chloride, tetrahydrofuran, acetonitrile, and the like are preferably used as the solvent.
[Wherein R ²¹ represents the same meaning as described above. ]

The compound represented by the formula (II′-1-a) is obtained by reacting the compound represented by the formula (II′-1-c) with the compound represented by the formula (II′-1-d). Can be obtained. This reaction is preferably carried out in the presence of a solvent such as methylene chloride, tetrahydrofuran and acetonitrile.
[Wherein R ²¹ represents the same meaning as described above. ]
In this reaction, a condensation catalyst such as dicyclohexylcarbodiimide may be used.

Examples of the compound represented by the formula (II′-1-c) include the following compounds.

Various compounds (II ′) can be obtained by substituting the compound represented by the formula (II′-1-c) with a desired compound represented by A ²¹ or R ²¹ . The compounds represented by formula (II′-1-c) and formula (II′-1-d) are easily available from the market.
Examples of compound (II ′) include the following.

Regarding the compound (II ′) represented by each of the formulas (aa′-1) to (aa′-6), the structural unit in which the methyl group corresponding to R ²¹ is replaced by a hydrogen atom is also represented by the compound (II ′). Specific examples can be given.

  The content of the structural unit (II) in the resin (A2) is in the range of 1 to 80 mol%, preferably in the range of 2 to 75 mol%, with respect to all the structural units of the resin (A2). More preferably, it is the range of 3-70 mol%, More preferably, it is the range of 5-65 mol%.

<Structural unit having acid labile group>
A structural unit having an acid labile group (hereinafter sometimes referred to as “acid labile structural unit”) is derived from a monomer having an acid labile group (hereinafter sometimes referred to as “acid labile monomer (a1)”). .
Examples of the acid labile group include a group represented by the formula (1) and a group represented by the formula (2).

[In the formula (1), R ^a1 , R ^a2 and R ^a3 each independently represent an alkyl group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms or a combination thereof. R ^a1 and R ^a2 are bonded to each other to form a divalent hydrocarbon group having 2 to 20 carbon atoms. * Represents a bond. ]
[In Formula (2), R ^{a1 ′} and R ^{a2 ′} each independently represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and R ^{a3 ′} represents a hydrocarbon group having 1 to 20 carbon atoms. R ^{a2 ′} and R ^{a3 ′} are bonded to each other to form a divalent hydrocarbon group having 2 to 20 carbon atoms, and —CH ₂ — contained in the hydrocarbon group and the divalent hydrocarbon group. May be replaced by -O- or -S-. ]

^Examples of the alkyl group represented by R ^a1 , R ^a2 and R ^a3 include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group.
The alicyclic hydrocarbon group represented by R ^a1 , R ^a2 and R ^a3 may be monocyclic or polycyclic, and the hydrogen atom contained in the alicyclic hydrocarbon group is an alkyl group. May be substituted. In this case, the carbon number of the alicyclic hydrocarbon group is 20 or less including the carbon number of the alkyl group.
Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following groups (* represents a bond).
Examples of the alicyclic hydrocarbon group substituted with an alkyl group include a methylcyclohexyl group, a dimethylcyclohexyl group, and a methylnorbornyl group.
In the formula (1), the alicyclic hydrocarbon group represented by R ^a1 , R ^a2 and R ^a3 preferably has 3 to 16 carbon atoms.

Examples of —C (R ^a1 ) (R ^a2 ) (R ^a3 ) in the case where R ^a1 and R ^a2 are bonded to each other to form a divalent hydrocarbon group include the following groups. The divalent hydrocarbon group preferably has 3 to 12 carbon atoms. In each formula, R ^a3 has the same meaning as described above, and * represents a bond to —O—.

Examples of the group represented by the formula (1) include a 1,1-dialkylalkoxycarbonyl group (in the formula (1), R ^a1 , R ^a2 and R ^a3 are alkyl groups, preferably tert-butoxycarbonyl). Group), 2-alkyladamantan-2-yloxycarbonyl group (in the formula (1), R ^a1 , R ^a2 and a carbon atom form an adamantyl group, and R ^a3 is an alkyl group) and 1- (adamantane) -1-yl) -1-alkylalkoxycarbonyl group (in the formula (1), R ^a1 and R ^a2 are alkyl groups, and R ^a3 is an adamantyl group).

Examples of the hydrocarbon group for R ^{a1 ′} , R ^{a2 ′} and R ^{a3 ′} include an alkyl group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group obtained by combining these.
Examples of the alkyl group and alicyclic hydrocarbon group are the same as those described above.
Aromatic hydrocarbon groups include phenyl, naphthyl, anthryl, p-methylphenyl, p-tert-butylphenyl, p-adamantylphenyl, tolyl, xylyl, cumenyl, mesityl, biphenyl Groups, phenanthryl groups, 2,6-diethylphenyl groups, aryl groups such as 2-methyl-6-ethylphenyl, and the like.
Examples of the divalent hydrocarbon group formed by combining R ^{a2 ′} and R ^{a3 ′} include a divalent aliphatic hydrocarbon group.

In Formula (2), it is preferable that at least one of R ^{a1 ′} and R ^{a2 ′} is a hydrogen atom.
Specific examples of the group represented by the formula (2) include the following groups. * Represents a bond.

  The acid labile monomer (a1) is preferably a monomer having an acid labile group and an ethylenically unsaturated bond, more preferably a (meth) acrylic monomer having an acid labile group.

  Among the (meth) acrylic monomers having an acid labile group, those having an alicyclic hydrocarbon group having 5 to 20 carbon atoms are preferable. If the resin composition (A2) having a structural unit derived from an acid labile monomer (a1) having a bulky structure such as an alicyclic hydrocarbon group is used in the resist composition, the resolution of the resist pattern can be improved. it can.

  As a structural unit derived from a (meth) acrylic monomer having an acid labile group (1), a structural unit represented by the formula (a1-1) or a structural unit represented by the formula (a1-2) is preferable. Can be mentioned. These may be contained independently and 2 or more types may be contained. In this specification, the structural unit represented by the formula (a1-1) and the structural unit represented by the formula (a1-2) are represented by the structural unit (a1-1) and the structural unit (a1-2), respectively. The monomer that derives the structural unit (a1-1) and the monomer that derives the structural unit (a1-2) may be referred to as a monomer (a1-1) and a monomer (a1-2), respectively.

[In Formula (a1-1) and Formula (a1-2),
L ^a1 and L ^a2 each independently represent —O— or ^* —O— (CH ₂ ) _k1 —CO—O—, k1 represents an integer of 1 to 7, and * represents a bond to —CO—. Represents a hand.
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 18 carbon atoms.
m1 represents the integer of 0-14.
n1 represents an integer of 0 to 10.
n1 ′ represents an integer of 0 to 3. ]

L ^a1 and L ^a2 are preferably —O— or ^* —O— (CH ₂ ) _k1 —CO—O—, and more preferably —O—. k1 is preferably an integer of 1 to 4, more preferably 1.
R ^a4 and R ^a5 are preferably methyl groups.
The alkyl group for R ^a6 and R ^a7 preferably has 6 or less carbon atoms.
The alicyclic hydrocarbon group for R ^a6 and R ^a7 may be monocyclic or polycyclic, and the hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with an alkyl group. . In this case, the carbon number of the alicyclic hydrocarbon group is 10 or less including the carbon number of the alkyl group. Specific examples include the same groups as the alicyclic hydrocarbon groups represented by R ^a1 , R ^a2 and R ^a3 in formula (1).
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.
n1 ′ is preferably 0 or 1.

As a monomer (a1-1), the monomer described in Unexamined-Japanese-Patent No. 2010-204646 is mentioned. Among these, a monomer represented by any one of formula (a1-1-1) to formula (a1-1-8) is preferable, and any one of formula (a1-1-1) to formula (a1-1-4) is preferable. The monomer represented by is more preferable.

Examples of the monomer (a1-2) include 1-ethylcyclopentan-1-yl (meth) acrylate, 1-ethylcyclohexane-1-yl (meth) acrylate, and 1-ethylcycloheptan-1-yl (meth). Examples include acrylate, 1-methylcyclopentan-1-yl (meth) acrylate, and 1-isopropylcyclopentan-1-yl (meth) acrylate. Monomers represented by the formula (a1-2-1) to the formula (a1-2-12) are preferred, and the formula (a1-2-3) to the formula (a1-2-4) or the formula (a1-2-9) The monomer represented by formula (a1-2-10) is more preferable, and the monomer represented by formula (a1-2-3) or formula (a1-2-9) is more preferable.

  When the resin (A2) includes the structural unit represented by the formula (a1-1) and / or the structural unit represented by the formula (a1-2), the total content thereof is the total structure of the resin (A2). It is 10-95 mol% normally with respect to a unit, Preferably it is 15-90 mol%, More preferably, it is 20-85 mol%.

As another acid labile monomer (a1), for example, a monomer represented by formula (a1-5) which is a (meth) acrylic monomer having an acid labile group (hereinafter referred to as “monomer (a1-5)”) May be used).
In formula (a1-5),
R ³¹ represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom.
Z ¹ represents a single bond or a * — [CH ₂ ] _k4 —CO—L ⁴ — group. Here, k4 represents an integer of 1 to 4. * Represents a bond with L ¹ .
L ¹ , L ² , L ³ and L ⁴ each independently represent —O— or —S—.
s1 represents an integer of 1 to 3.
s1 ′ represents an integer of 0 to 3.

In formula (a1-5), R ³¹ is preferably a hydrogen atom, a methyl group, or a trifluoromethyl 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.
s1 ′ is preferably an integer of 0 to 2.
Z ¹ is preferably a single bond or * —CH ₂ —CO—O—.

Examples of the monomer (a1-5) include the following monomers.

  When the resin (A2) has a structural unit derived from the monomer (a1-5), the content is preferably from 1 to 50 mol%, more preferably from 3 to 45 mol, based on all structural units of the resin (A2). % Is more preferable, and 5 to 40 mol% is more preferable.

<Acid stable monomer>
As an acid stable monomer, Preferably, the monomer which has a hydroxyl group or a lactone ring is mentioned. Acid-stable monomer having a hydroxy group (hereinafter sometimes referred to as “acid-stable monomer having a hydroxy group (a2)”) or acid-stable monomer having a lactone ring (hereinafter referred to as “acid-stable monomer having a lactone ring (a3)”) If a resin having a structural unit derived from (sometimes) is used, the resolution of the resist pattern and the adhesion to the substrate can be improved.

<Acid-stable monomer having a hydroxy group (a2)>
When the resist composition is used for high energy beam exposure such as KrF excimer laser exposure (248 nm), electron beam or EUV (ultra-ultraviolet light), the acid-stable monomer (a2) having a hydroxy group is preferably a hydroxystyrene. An acid stable monomer having a certain phenolic hydroxy group is used. When using short-wavelength ArF excimer laser exposure (193 nm) or the like, the acid-stable monomer (a2) having a hydroxy group is preferably an acid-stable monomer having a hydroxyadamantyl group represented by the formula (a2-1). use. The acid-stable monomer (a2) having a hydroxy group may be used alone or in combination of two or more.

Examples of the acid stable monomer having a hydroxyadamantyl group include a monomer represented by the formula (a2-1).
In formula (a2-1),
L ^a3 represents —O— or ^* —O— (CH ₂ ) _k2 —CO—O—,
k2 represents an integer of 1 to 7. * Represents a bond with -CO-.
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, -O -, - O- (CH 2) f1 -CO-O- and is (wherein f1 is an integer from 1 to 4), more preferably Is —O—.
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 monomer (a2-1) which has a hydroxyadamantyl group, the monomer described in Unexamined-Japanese-Patent No. 2010-204646 is mentioned, for example. A monomer represented by any one of formula (a2-1-1) to formula (a2-1-6) is preferable, and represented by any one of formula (a2-1-1) to formula (a2-1-4). The monomer represented by Formula (a2-1-1) or Formula (a2-1-3) is more preferable.

  When the resin (A2) includes a structural unit derived from the monomer represented by the formula (a2-1), the content is usually 3 to 45 mol% with respect to all the structural units of the resin (A2). , Preferably it is 3-40 mol%, More preferably, it is 3-35 mol%, More preferably, it is 3-20 mol%.

<Acid-stable monomer having a lactone ring (a3)>
The lactone ring possessed by the acid stable monomer (a3) may be, for example, a monocycle such as a β-propiolactone ring, γ-butyrolactone ring, or δ-valerolactone ring, and a monocyclic lactone ring and other rings The condensed ring may be used. Among these lactone rings, a γ-butyrolactone ring or a condensed ring of γ-butyrolactone ring and another ring is preferable.

  The acid-stable monomer (a3) having a lactone ring is preferably represented by the formula (a3-1), the formula (a3-2) or the formula (a3-3). These 1 type may be used independently and may use 2 or more types together.

In formula (a3-1), formula (a3-2) and formula (a3-3),
L ^a4 , L ^a5 and L ^a6 each independently represent —O— or ^* —O— (CH ₂ ) _k3 —CO—O—.
k3 represents an integer of 1 to 7. * Represents a bond with -CO-.
R ^a18 , R ^a19 and R ^a20 each independently represents a hydrogen atom or a methyl group.
R ^a21 represents an alkyl group having 1 to 4 carbon atoms.
p1 represents an integer of 0 to 5.
R ^a22 and R ^a23 each independently represent a carboxy group, a cyano group, or an alkyl group having 1 to 4 carbon atoms.
q1 and r1 each independently represents an integer of 0 to 3. When p1 is 2 or more, a plurality of R ^a21 are the same or different, when q1 is 2 or more, a plurality of R ^a22 are the same or different, and when r1 is 2 or more, a plurality of R ^a23 are the same or different Different.

^Examples of the alkyl group for R ^a21 , R ^a22 and R ^a23 include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, a tert-butyl group, and a sec-butyl group.

In formula (a3-1), formula (a3-2) and formula (a3-3), L ^a4 , L ^a5 and L ^a6 are each independently —O— or ^* —O— (CH ₂ ) _k3 —. CO-O- is preferable, and -O- is more preferable. k3 is preferably an integer of 1 to 4, more preferably 1.
R ^a18 , R ^a19 , R ^a20 and 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 each independently preferably 0 to 2, more preferably 0 or 1.

  Examples of the acid-stable monomer (a3) having a lactone ring include monomers described in JP 2010-204646 A. Formula (a3-1-1) to Formula (a3-1-4), Formula (a3-2-1) to Formula (a3-2-4), Formula (a3-3-1) to Formula (a3-3) -4) is preferable, and is represented by formula (a3-1-1) to formula (a3-1-2), formula (a3-2-3) to formula (a3-2-4). A monomer is more preferable, and a monomer represented by formula (a3-1-1) or formula (a3-2-3) is more preferable.

  When the resin (A2) includes a structural unit derived from the acid-stable monomer (a3) having a lactone ring, the content is usually 5 to 70 mol% with respect to all the structural units of the resin (A2), Preferably it is 10-65 mol%, More preferably, it is 10-60 mol%.

When the resin (A2) is a resin composed only of the structural unit (II) and the acid labile structural unit, these contents are respectively relative to the total structural unit of the resin (A2),
Structural unit (II); 1-80 mol%
Acid-labile structural unit; 20-99 mol%
Is preferred,
Structural unit (II); 5-65 mol%
Acid labile structural unit; 35-95 mol%
Is more preferable.

When the resin (A2) is a resin composed of the structural unit (II), the acid labile structural unit, and the acid stable structural unit, these contents are respectively relative to the total structural unit of the resin (A2).
Structural unit (II); 1-80 mol%
Acid-labile structural unit; 17-96 mol%
Acid stable structural unit; 3-82 mol%
Is preferred,
Structural unit (II); 2-75 mol%
Acid-labile structural unit; 20 to 93 mol%
Acid stable structural unit; 5-78 mol%
Is more preferred,
Structural unit (II); 5-65 mol%
Acid-labile structural unit; 30 to 90 mol%
Acid stable structural unit; 5 to 65 mol%
Is more preferable.

  Resin (A2) contains 15 mol% or more of structural units derived from a monomer having an adamantyl group (particularly monomer (a1-1) having an acid labile group) with respect to acid labile monomer (a1) It is preferable. When the ratio of the monomer having an adamantyl group is increased, the dry etching resistance of the resist is improved.

  The resin (A2) is preferably a copolymer of a monomer represented by the formula (II ′), an acid labile monomer (a1), and an acid stable monomer. In this copolymer, the acid labile monomer (a1) is more preferably at least one of a monomer (a1-1) having an adamantyl group and a monomer (a1-2) having a cyclohexyl group or a cyclopentyl group (further, The monomer (a1-1)) having an adamantyl group is preferable. The acid stable monomer is preferably an acid stable monomer (a2) having a hydroxy group and / or an acid stable monomer (a3) having a lactone ring. The acid-stable monomer (a2) having a hydroxy group is preferably an acid-stable monomer (a2-1) having a hydroxyadamantyl group, and the acid-stable monomer (a3) having a lactone ring is more preferably a γ-butyrolactone ring. The acid-stable monomer (a3-1) and the acid-stable monomer (a3-2) having a condensed ring of a γ-butyrolactone ring and a norbornane ring.

Each structural unit constituting the resin (A2) may be contained alone or in combination of two or more, and a known polymerization method (for example, radical polymerization method) using a monomer for deriving these structural units. Can be manufactured by.
The weight average molecular weight of the resin (A2) is preferably 2,500 or more (more preferably 3,000 or more, more preferably 4,000 or more), 50,000 or less (more preferably 30,000 or less, further preferably 15,000 or less).

  In the resin (A), the resin (A1) and the resin (A2) are, for example, 0.01: 10 to 5:10, preferably 0.05: 10 to 3:10, and more preferably 0.1: 10. To 2:10, particularly preferably 0.2: 10 to 1:10 (mass ratio).

<Resin other than resin (A1) and (A2)>
The resist composition of the present invention includes resins other than the above-described resins (A1) and (A2), for example, a structural unit derived from the acid-labile monomer (a1) described above, a structural unit derived from an acid-stable monomer, and A resin having at least one structural unit selected from structural units derived from known monomers used in the field may be contained.
When the resist composition of this invention contains resin other than resin (A1) and (A2), these content rates are normal with respect to the total amount of resin (A) contained in the resist composition of this invention. It is 0.1-50 mass%, Preferably it is 0.5-30 mass%, More preferably, it is 1-20 mass%.

  In the resist composition of the present invention, the resin content is preferably 80% by mass or more and 99% by mass or less in the solid content of the resist composition. In the present specification, the “solid content in the composition” means the total of resist composition components excluding the solvent (E) described later. The solid content in the composition and the resin content relative thereto can be measured, for example, by a known analytical means such as liquid chromatography or gas chromatography.

<Acid generator (B)>
The acid generator (B) is classified into a nonionic type and an ionic type, and any of them may be used in the resist composition of the present invention. Nonionic acid generators include organic halides, sulfonate esters (for example, 2-nitrobenzyl ester, aromatic sulfonate, oxime sulfonate, N-sulfonyloxyimide, N-sulfonyloxyimide, sulfonyloxyketone, diazonaphthoquinone 4). -Sulfonate), sulfones (for example, disulfone, ketosulfone, sulfonyldiazomethane) and the like. Examples of the ionic acid generator include onium salts containing onium cations (for example, diazonium salts, phosphonium salts, sulfonium salts, iodonium salts). Examples of the anion of the onium salt include a sulfonate anion, a sulfonylimide anion, and a sulfonylmethide anion.

  Examples of the acid generator (B) include JP-A 63-26653, JP-A 55-164824, JP-A 62-69263, JP-A 63-146038, JP-A 63-163452, JP-A-62-153853, JP-A-63-146029, US Pat. No. 3,779,778, US Pat. No. 3,849,137, German Patent No. 3914407, European Patent No. 126,712 The compound which generate | occur | produces an acid by the radiation as described in etc. can be used.

  The acid generator (B) is preferably a fluorine-containing acid generator, more preferably a sulfonate represented by the 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 saturated hydrocarbon group having 1 to 24 carbon atoms, and the hydrogen atom contained in the saturated hydrocarbon group may be replaced by a fluorine atom or a hydroxy group, and methylene constituting the saturated hydrocarbon group The group may be replaced by an oxygen atom or a carbonyl group.
Y represents a hydrogen atom, a fluorine atom, or an optionally substituted alicyclic hydrocarbon group having 3 to 18 carbon atoms, and the methylene group constituting the alicyclic hydrocarbon group is an oxygen atom, A sulfonyl group or a carbonyl group may be substituted.
Z ⁺ represents an organic cation. ]

Examples of the perfluoroalkyl group of Q ¹ and Q ² include a trifluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluoroisopropyl group, a perfluorobutyl group, a perfluorosec-butyl group, a perfluorotert-butyl group, and a perfluoropentyl group. And perfluorohexyl group.
Q ¹ and Q ² are each independently preferably a trifluoromethyl group or a fluorine atom, more preferably a fluorine atom.

Examples of the divalent saturated hydrocarbon group represented by L ^b1 include a linear alkanediyl group, a branched alkanediyl group, a monocyclic or polycyclic alicyclic saturated hydrocarbon group, A combination of two or more of the groups may be used.
Specifically, 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, Linear alkanediyl groups such as 17-diyl group, ethane-1,1-diyl group, propane-1,1-diyl group and propane-2,2-diyl group;
An alkyl group (particularly an alkyl group having 1 to 4 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group); For example, 1-methylbutane-1,3-diyl group, 2-methylpropane-1,3-diyl group, 2-methylpropane-1,2-diyl group, pentane-1,4 A branched alkanediyl group such as a diyl group or 2-methylbutane-1,4-diyl group;
Monocyclic 2 which is a cycloalkanediyl group such as cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane-1,4-diyl group, cyclooctane-1,5-diyl group Valent alicyclic saturated hydrocarbon group;
Polycyclic divalent alicyclic saturated hydrocarbon such as norbornane-1,4-diyl group, norbornane-2,5-diyl group, adamantane-1,5-diyl group, adamantane-2,6-diyl group, etc. Groups and the like.

Examples of the saturated hydrocarbon group represented by L ^{b1 in} which the methylene group is replaced with an oxygen atom or a carbonyl group include the same as those in formulas (b1-1) to (b1-7). In addition, Formula (b1-1)-Formula (b1-7) have described the right and left according to Formula (B1), and among two bonds represented by *, C (Q ¹ ) Combined with (Q ² )-and combined with -Y on the right side. The same applies to specific examples of the following formulas (b1-1) to (b1-7).

In formula (b1-1) to formula (b1-7),
L ^b2 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms.
L ^b3 represents a single bond or a divalent saturated hydrocarbon group having 1 to 19 carbon atoms.
L ^b4 represents a divalent saturated hydrocarbon group having 1 to 20 carbon atoms. However, the total carbon number upper limit of L ^b3 and L ^b4 is 20.
L ^b5 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms.
L ^b6 represents a divalent saturated hydrocarbon group having 1 to 22 carbon atoms. However, the total carbon number upper limit of L ^b5 and L ^b6 is 22.
L ^b7 represents a single bond or a divalent saturated hydrocarbon group having 1 to 22 carbon atoms.
L ^b8 represents a divalent saturated hydrocarbon group having 1 to 22 carbon atoms. However, the total carbon number upper limit of L ^b7 and L ^b8 is 23.
L ^b9 and L ^b10 each independently represent a divalent saturated hydrocarbon group having 1 to 18 carbon atoms. However, the total carbon number upper limit of L ^b9 and L ^b10 is 20.
L ^b11 and L ^b12 represent a single bond or a divalent saturated hydrocarbon group having 1 to 18 carbon atoms.
L ^b13 represents a divalent saturated hydrocarbon group having 1 to 19 carbon atoms. However, the upper limit of the total carbon number of L ^b11 , L ^b12 and L ^b13 is 19.
L ^b14 and L ^b15 each independently represent a single bond or a divalent saturated hydrocarbon group having 1 to 20 carbon atoms.
L ^b16 represents a divalent saturated hydrocarbon group having 1 to 21 carbon atoms. However, the upper limit of the total carbon number of L ^b14 , L ^b15 and L ^b16 is 21.

Among them, L ^b1 is preferably any one of formula (b1-1) to formula (b1-4), more preferably formula (b1-1) or formula (b1-2), and still more preferably formula (b1-1). And particularly preferably a divalent group represented by the formula (b1-1) in which L ^b2 is a single bond or —CH ₂ —.

Examples of the divalent group represented by the formula (b1-1) include the following.

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.

Examples of the divalent group represented by the formula (b1-7) include the following.

Specific examples when the hydrogen atom contained in the aliphatic saturated hydrocarbon group of L ^b1 is substituted with a fluorine atom or a hydroxy group include the following.

  Examples of the alicyclic hydrocarbon group represented by Y include groups represented by any of formulas (Y1) to (Y26).

  Among them, the alicyclic hydrocarbon group of Y is preferably a group represented by any one of the formulas (Y1) to (Y19), and more preferably the formula (Y11), the formula (Y14), the formula ( Y15) or a group represented by formula (Y19), more preferably a group represented by formula (Y11) or formula (Y14).

Examples of the substituent of the alicyclic hydrocarbon group represented by Y include a halogen atom, a hydroxy group, an alkyl group having 1 to 12 carbon atoms, a hydroxy group-containing alkyl group having 1 to 12 carbon atoms, and 3 to 3 carbon atoms. 16 alicyclic hydrocarbon groups, alkoxy groups having 1 to 12 carbon atoms, aromatic hydrocarbon groups having 6 to 18 carbon atoms, aralkyl groups having 7 to 21 carbon atoms, acyl groups having 2 to 4 carbon atoms, glycidyloxy Group or — (CH ₂ ) _j2 —O—CO—R ^b1 group (wherein R ^b1 is an alkyl group having 1 to 16 carbon atoms, an alicyclic hydrocarbon group having 3 to 16 carbon atoms, or 6 to 6 carbon atoms). Represents an aromatic hydrocarbon group of 18. j2 represents an integer of 0 to 4).

Examples of the hydroxy group-containing alkyl group include a hydroxymethyl group and a hydroxyethyl group.
Examples of the aromatic hydrocarbon group include phenyl group, naphthyl group, anthryl group, p-methylphenyl group, p-tert-butylphenyl group, p-adamantylphenyl group; tolyl group, xylyl group, cumenyl group, mesityl group. And aryl groups such as a biphenyl group, a phenanthryl group, a 2,6-diethylphenyl group, and a 2-methyl-6-ethylphenyl group.
Examples of the aralkyl group include a benzyl group, a phenethyl group, a phenylpropyl group, a naphthylmethyl group, and a naphthylethyl group.
Examples of the alkoxy group include methoxy group, ethoxy group, propoxy group, butoxy group, pentyloxy group, hexyloxy group, heptyloxy group, octyloxy group, decyloxy group and dodecyloxy group.
Examples of the acyl group include those in which an alkyl group such as an acetyl group, a propionyl group, or a butyryl group is bonded to a carbonyl group.
Examples of the halogen atom, alicyclic hydrocarbon group, and alkyl group are the same as those described above.

Examples of Y include the following.

  Y is preferably an alicyclic hydrocarbon group having 3 to 18 carbon atoms which may have a substituent, more preferably an adamantyl group which may have a substituent, and more preferably an adamantyl group. A group, a hydroxyadamantyl group or an oxoadamantyl group.

The sulfonate anion in the sulfonate represented by the formula (B1) is preferably an anion represented by the formula (b1-1-1) to the formula (b1-1-9). In the following formulas, the definitions of the symbols have the same meaning as described above, and R ^b2 and R ^b3 each independently represent an alkyl group having 1 to 4 carbon atoms (preferably a methyl group).
Specific examples of the sulfonate anion in the sulfonate represented by the formula (B1) include anions described in JP-A No. 2010-204646.

Examples of the organic cation of Z ⁺ include organic onium cations such as organic sulfonium cation, organic iodonium cation, organic ammonium cation, benzothiazolium cation, and organic phosphonium cation, and preferably organic sulfonium cation or organic iodonium cation. More preferably an arylsulfonium cation.
Z ⁺ is preferably a cation represented by any one of formulas (b2-1) to (b2-4).

In formula (b2-1) to formula (b2-4),
R ^{b4 to} R ^b6 each independently represents a hydrocarbon group having 1 to 36 carbon atoms, and this hydrocarbon group is an aliphatic hydrocarbon group having 1 to 30 carbon atoms or an alicyclic group having 3 to 36 carbon atoms. A hydrocarbon group and an aromatic hydrocarbon group having 6 to 36 carbon atoms are preferred. The hydrogen atom contained in the aliphatic hydrocarbon group is a hydroxy group, an alkoxy group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms, or an aromatic hydrocarbon group having 6 to 18 carbon atoms. The hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with a halogen atom, an aliphatic hydrocarbon group having 1 to 18 carbon atoms, an acyl group having 2 to 4 carbon atoms, or a glycidyloxy group. The hydrogen atom contained in the aromatic hydrocarbon group may be substituted with a halogen atom, a hydroxy group or an alkoxy group having 1 to 12 carbon atoms. R ^b4 and R ^b5 may be bonded to each other to form a ring together with the sulfur atom.

R ^b7 and R ^b8 each independently represent a hydroxy group, an aliphatic hydrocarbon group having 1 to 18 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms.
m2 and n2 each independently represent an integer of 0 to 5, when m2 is 2 or more, the plurality of R ^b7 are the same or different, and when n2 is 2 or more, the plurality of R ^b8 are the same or different. .

R ^b9 and R ^b10 each independently represent an aliphatic hydrocarbon group having 1 to 36 carbon atoms or an alicyclic hydrocarbon group having 3 to 36 carbon atoms, or R ^b9 and R ^{b10 taken} together Forms a ring containing a sulfur atom to which. The methylene group contained in the ring may be replaced with an oxygen atom, a sulfur atom or a carbonyl group.
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 ^b11 and R ^b12 may be combined to form a 3- to 12-membered ring (preferably a 3- to 7-membered ring) with —CH—CO— to which they are bonded. —CH ₂ — contained in the ring may be replaced by —O—, —S— or —CO—.
R ^b12 represents an aliphatic hydrocarbon group having 1 to 30 carbon atoms, an alicyclic hydrocarbon group having 3 to 36 carbon atoms, or an aromatic hydrocarbon group having 6 to 36 carbon atoms, and the aliphatic hydrocarbon group includes The hydrogen atom contained may be substituted with an aromatic hydrocarbon group having 6 to 36 carbon atoms, and the hydrogen atom contained in the aromatic hydrocarbon group is an alkyl group having 1 to 12 carbon atoms or 1 carbon atom. It may be substituted with an -12 alkoxy group, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, or an alkylcarbonyloxy group having 1 to 12 carbon atoms.

R ^{b13 to} R ^b18 each independently represent a hydroxy group, an aliphatic hydrocarbon 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, multiple R ^b13 are the same or different, when p2 is 2 or more, multiple R ^b14 are the same or different, and when q2 is 2 or more, multiple R ^b15 are the same or different , When r2 is 2 or more, a plurality of R ^b16 are the same or different, when s2 is 2 or more, a plurality of R ^b17 are the same or different, and when t2 is 2 or more, a plurality of R ^b18 are the same or different Different.

Examples of the aliphatic hydrocarbon group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, octyl group and 2-ethylhexyl group. Etc. In particular, the aliphatic hydrocarbon group represented by R ^{b9 to} R ^b12 preferably has 1 to 12 carbon atoms.
Examples of the aliphatic hydrocarbon group in which a hydrogen atom is substituted with an alicyclic hydrocarbon group include a 1- (adamantan-1-yl) alkane-1-yl group.

The alicyclic hydrocarbon group may be monocyclic or polycyclic, and the hydrogen atom contained in the alicyclic hydrocarbon group may be substituted with an alkyl group. In this case, the carbon number of the alicyclic hydrocarbon group is 20 or less including the carbon number of the alkyl group. Examples of the monocyclic alicyclic hydrocarbon group include cycloalkyl groups such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, and a cyclodecyl group. Examples of the polycyclic alicyclic hydrocarbon group include a decahydronaphthyl group, an adamantyl group, a norbornyl group, and the following groups (* represents a bond).
In particular, the alicyclic hydrocarbon group of R ^{b9 to} R ^b11 preferably has 3 to 18 carbon atoms, more preferably 4 to 12 carbon atoms.
Examples of the alicyclic hydrocarbon group in which a hydrogen atom is substituted with an alkyl group include a methylcyclohexyl group, a dimethylcyclohexyl group, a 2-alkyladamantan-2-yl group, and a 1- (adamantan-1-yl) alkane. A -1-yl group, a methylnorbornyl group, an isobornyl group, etc. are mentioned.
As an aromatic hydrocarbon group, phenyl group, naphthyl group, anthryl group, p-methylphenyl group, p-ethylphenyl group, p-tert-butylphenyl group, p-cyclohexylphenyl group, p-methoxyphenyl group And aryl groups such as p-adamantylphenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, biphenylyl group, phenanthryl group, 2,6-diethylphenyl group, 2-methyl-6-ethylphenyl, and the like.
Examples of the alkyl group in which a hydrogen atom is substituted with an aromatic hydrocarbon group, that is, an aralkyl group, include a benzyl group, a phenethyl group, a phenylpropyl group, a trityl group, a naphthylmethyl group, and a naphthylethyl group.
When the aromatic hydrocarbon group includes an aliphatic hydrocarbon group or an alicyclic hydrocarbon group, the aliphatic hydrocarbon group having 1 to 18 carbon atoms and the alicyclic hydrocarbon having 3 to 18 carbon atoms Groups are preferred.

As the alkoxy group, methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, sec-butoxy group, tert-butoxy group, n-pentyloxy group, n-hexyloxy group, heptyloxy group Octyloxy group, 2-ethylhexyloxy group, nonyloxy group, decyloxy group, undecyloxy group, dodecyloxy group and the like.
As an aromatic hydrocarbon group by which the hydrogen atom was substituted by the alkoxy group, 4-methoxyphenyl group etc. are mentioned, for example.
Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.
Examples of the acyl group include an acetyl group, a propionyl group, and a butyryl group.
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.

The ring containing a sulfur atom which may be formed by combining R ^b4 and R ^b5 is any of monocyclic, polycyclic, aromatic, non-aromatic, saturated and unsaturated rings. If it contains one or more sulfur atoms, it may further contain one or more sulfur atoms and / or one or more oxygen atoms. As the ring, a ring having 3 to 18 carbon atoms is preferable, and a ring having 4 to 18 carbon atoms is more preferable.

Examples of the ring formed together with the sulfur atom to which R ^b9 and R ^b10 are bonded include, for example, a thiolane-1-ium ring (tetrahydrothiophenium ring), a thian-1-ium ring, and 1,4-oxathian-4-ium. A ring etc. are mentioned.
Examples of the ring formed with —CH—CO— in which R ^b11 and R ^b12 are bonded include an oxocycloheptane ring, an oxocyclohexane ring, an oxonorbornane ring, and an oxoadamantane ring.

Among the cations (b2-1) to (b2-4), the cation (b2-1) is preferable, and the cation represented by the formula (b2-1-1) is more preferable. Are triphenylsulfonium cations (in formula (b2-1-1), v2 = w2 = x2 = 0), diphenyltolylsulfonium cations (in formula (b2-1-1), v2 = w2 = 0, x2 = 1 And R ^b21 is a methyl group.) Or a tolylsulfonium cation (in formula (b2-1-1), v2 = w2 = x2 = 1, and R ^b19 , R ^b20 and R ^b21 are all methyl. Group.)

In formula (b2-1-1),
R ^{b19 to} R ^b21 are each independently a halogen atom (more preferably a fluorine atom) hydroxy group, an aliphatic hydrocarbon group having 1 to 18 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkyl group having 3 to 18 carbon atoms. Represents an alicyclic hydrocarbon group. It is also possible that two selected from R ^b19 to R ^b21 together form a ring containing a sulfur 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 are the same or different, when w2 is 2 or more, the plurality of R ^b20 are the same or different, and when x2 is 2 or more, the plurality of R ^b21 are the same or different. .

Among them, R ^{b19 to} R ^b21 are preferably each independently a halogen atom (more preferably a fluorine atom), a hydroxy group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. It is.

  Specific examples of the cation represented by the formula (b2-1-1) include cations described in JP 2010-204646 A.

  The acid generator (B1) is a combination of the above-described sulfonate anion and organic cation. The above-mentioned anion and cation can be arbitrarily combined, and preferably a combination of any one of anion (b1-1-1) to anion (b1-1-9) and cation (b2-1-1), and A combination of any one of anions (b1-1-3) to (b1-1-5) and a cation (b2-3) may be mentioned.

  The acid generator (B1) is preferably a salt represented by each of the formulas (B1-1) to (B1-20), more preferably a salt containing an arylsulfonium cation. Preferably, Formula (B1-1), Formula (B1-2), Formula (B1-3), Formula (B1-6), Formula (B1-7), Formula (B1-11), Formula (B1-12) ), Formula (B1-13), formula (B1-14), formula (B1-18), formula (B1-19) or salt represented by formula (B1-20).

The content of the acid generator (B) is preferably 1 part by mass or more (more preferably 3 parts by mass or more), preferably 30 parts by mass or less (more preferably 25 parts by mass) with respect to 100 parts by mass of the resin (A). Part or less).
The acid generator (B) may contain 1 type independently, and may contain the multiple types of acid generator simultaneously.

<Solvent (E)>
The content rate of the solvent (E) contained in the resist composition of this invention is 90 mass% or more in a resist composition, for example, Preferably it is 92 mass% or more, More preferably, it is 94 mass% or more, for example, 99.9. It is not more than mass%, preferably not more than 99 mass%. The content rate of a solvent (E) can be measured by well-known analysis means, such as a liquid chromatography or a gas chromatography, for example.

  Examples of the solvent (E) 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 And esters such as ethyl pyruvate; ketones such as acetone, methyl isobutyl ketone, 2-heptanone and cyclohexanone; cyclic esters such as γ-butyrolactone; A solvent (E) may be used by containing 1 type, and may contain 2 or more types.

<Basic compound (C)>
The basic compound means a compound having a property of capturing an acid, particularly a compound having a property of capturing an acid generated from an acid generator, and is referred to as a quencher in this technical field.

  The basic compound (C) is preferably a basic nitrogen-containing organic compound, and examples thereof include amines and ammonium salts. Examples of amines include aliphatic amines and aromatic amines. Aliphatic amines include primary amines, secondary amines and tertiary amines. The basic compound (C) is preferably a compound represented by any of the formulas (C1) to (C8) and (C1-1), more preferably represented by the formula (C1-1). It is a compound.

[In the formula (C1),
R ^c1 , R ^c2 and R ^c3 are each independently 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 the aromatic hydrocarbon group The hydrogen atom contained is 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. It may be. ]

[In the formula (C1-1),
R ^c2 and R ^c3 represent the same meaning as described 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 are the same or different. ]

[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.
n3 represents an integer of 0 to 8, and when n3 is 2 or more, the plurality of R ^c9 are the same or different. ]

[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 represents an integer of 0 to 3, and when o3 is 2 or more, the plurality of R ^c14 are the same or different, and when p3 is 2 or more, the plurality of R ^c15 are 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. ]

[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 represent an integer of 0 to 3, and when q3 is 2 or more, the plurality of R ^c18 are the same or different, and when r3 is 2 or more, the plurality of R ^c19 are the same. Or when different and when s3 is 2 or more, the plurality of R ^c20 are 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. ]

In formula (C1) to formula (C8) and formula (C1-1), the alkyl group, alicyclic hydrocarbon group, aromatic hydrocarbon group, alkoxy group, alkanediyl group are the same as those described above. Is mentioned.
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.

  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- Examples include diphenylethane, 4,4′-diamino-3,3′-dimethyldiphenylmethane, 4,4′-diamino-3,3′-diethyldiphenylmethane, and preferably diisopropyl. Piruanirin. Particularly preferred include 2,6-diisopropylaniline.

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 Ammonium hydroxide, tetra-n-butylammonium salicylate, choline and the like can be mentioned.

  The content of the basic compound (C) in the solid content of the resist composition is preferably about 0.01 to 5% by mass, more preferably about 0.01 to 3% by mass, and particularly preferably 0.8. It is about 01 to 1% by mass.

<Other components (hereinafter sometimes referred to as “other components (F)”)>
The resist composition of this invention may contain the other component (F) as needed. The other component (F) is not particularly limited, and additives known in the resist field, such as sensitizers, dissolution inhibitors, surfactants, stabilizers, dyes, and the like can be used.

<Preparation of resist composition>
The resist composition of the present invention is obtained by mixing the resin (A) and the acid generator (B), and the solvent (E), basic compound (C) and other components (F) used as necessary. Can be prepared. 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, the solubility with respect to solvent (E), such as resin. 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.
After mixing each component, it is preferable to filter using a filter having a pore size of about 0.003 to 0.2 μm.

<Method for producing resist pattern>
The method for producing a resist pattern of the present invention comprises:
(1) The process of apply | coating the resist composition of this invention on a board | substrate,
(2) The process of drying the composition after application | coating and forming a composition layer,
(3) a step of exposing the composition layer,
(4) The process of heating the composition layer after exposure, (5) The process of developing the composition layer after a heating is included.

  Application of the resist composition onto the substrate can be performed by a commonly used apparatus such as a spin coater. Examples of the substrate include an inorganic substrate such as a silicon wafer. Before applying the resist composition, the substrate may be washed or an antireflection film or the like may be formed.

The composition layer is formed by drying the composition after application. Drying is performed, for example, by evaporating the solvent using a heating device such as a hot plate (so-called pre-baking) or using a decompression device to form a composition layer from which the solvent has been removed. The temperature in this case is preferably about 50 to 200 ° C., for example. The pressure is preferably about 1 to 1.0 × 10 ⁵ Pa.

The obtained composition layer is usually exposed using an exposure machine. The exposure machine may be an immersion exposure machine. At this time, exposure is usually performed through a mask corresponding to a required pattern. Exposure light sources include those that emit laser light in the ultraviolet region such as KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), F ₂ excimer laser (wavelength 157 nm), solid-state laser light source (YAG or semiconductor laser) Etc.) Using various lasers such as those that convert wavelength of laser light from the laser and emit harmonic laser light in the far-ultraviolet region or vacuum ultraviolet region, those that irradiate electron beams or extreme ultraviolet light (EUV), etc. Can do.

  The composition layer after exposure is subjected to heat treatment (so-called post-exposure baking) in order to promote the deprotection group reaction of the resin (A). As heating temperature, it is about 50-200 degreeC normally, Preferably it is about 70-150 degreeC.

  The heated composition layer is usually developed using a developer using a developing device. Examples of the developing method include a dipping method, a paddle method, a spray method, and a dynamic dispensing method. The development temperature is preferably 5 to 60 ° C., and the development time is preferably 5 to 300 seconds.

When producing a positive resist pattern from the resist composition of the present invention, an alkaline developer is used as the developer. The alkaline developer may be various alkaline aqueous solutions used in this field. Examples thereof include an aqueous solution of tetramethylammonium hydroxide and (2-hydroxyethyl) trimethylammonium hydroxide (commonly called choline). The alkali developer may contain a surfactant.
It is preferable to wash the resist pattern with ultrapure water after development, and then remove the water remaining on the substrate and the pattern.

In the case of producing a negative resist pattern from the resist composition of the present invention, a developer containing an organic solvent as a developer (hereinafter sometimes referred to as “organic developer”) is used.
Organic solvents contained in the organic developer include ketone solvents such as 2-hexanone and 2-heptanone; glycol ether ester solvents such as propylene glycol monomethyl ether acetate; ester solvents such as butyl acetate; glycols such as propylene glycol monomethyl ether Examples include ether solvents; amide solvents such as N, N-dimethylacetamide; aromatic hydrocarbon solvents such as anisole.
In the organic developer, the content of the organic solvent is preferably 90% by mass or more and 100% by mass or less, more preferably 95% by mass or more and 100% by mass or less, and still more preferably only the organic solvent.
Among them, the organic developer is preferably a developer containing butyl acetate and / or 2-heptanone. In the organic developer, the total content of butyl acetate and 2-heptanone is preferably 50% by mass to 100% by mass, more preferably 90% by mass to 100% by mass, and substantially butyl acetate and / or 2 -More preferred is heptanone alone.
The organic developer may contain a surfactant. The organic developer may contain a trace amount of water.
At the time of development, the development may be stopped by substituting a solvent of a different type from the organic developer.

It is preferable to wash the developed resist pattern with a rinse solution. The rinsing liquid is not particularly limited as long as it does not dissolve the resist pattern, and a solution containing a general organic solvent can be used, and an alcohol solvent or an ester solvent is preferable.
After the cleaning, it is preferable to remove the rinse solution remaining on the substrate and the pattern.

<Application>
The resist composition of the present invention is a resist composition for KrF excimer laser exposure, a resist composition for ArF excimer laser exposure, a resist composition for electron beam (EB) exposure, or a resist composition for EUV exposure, particularly a liquid. It is suitable as a resist composition for immersion exposure and useful for fine processing of semiconductors.

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 structure of the compound was confirmed by MASS (LC: Agilent 1100 type, MASS: Agilent LC / MSD type or LC / MSD TOF type).
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 obtained by gel permeation chromatography under the following conditions.
Apparatus: HLC-8120GPC type (manufactured by Tosoh Corporation)
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)

Synthesis Example 1 (Synthesis of Monomer (MM))
9.60 parts of the compound represented by the formula (M-2), 38.40 parts of tetrahydrofuran and 5.99 parts of pyridine were mixed with stirring at 23 ° C. for 30 minutes and cooled to 0 ° C. While maintaining the same temperature, 14.00 parts of the compound represented by the formula (M-1) is added to the obtained mixture over 1 hour, and the temperature is further increased to about 10 ° C. Stir for 1 hour. The reaction mixture containing the compound represented by the formula (M-3) thus obtained was added to the compound (1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride) 14 represented by the formula (M-4). .51 parts and 8.20 parts of the compound represented by the formula (M-5) were added and stirred at 23 ° C. for 3 hours. To the obtained reaction solution, 271.95 parts of ethyl acetate and 16.57 parts of 5% aqueous hydrochloric acid were added, and the mixture was stirred at 23 ° C. for 30 minutes. To the organic layer recovered by standing and separating, 63.64 parts of a saturated aqueous sodium hydrogen carbonate solution was added, stirred at 23 ° C. for 30 minutes, and allowed to stand and separate to wash the organic layer. Such washing operation was repeated twice. The organic layer after washing was charged with 67.9 parts of ion-exchanged water, stirred at 23 ° C. for 30 minutes, allowed to stand, and separated to wash the organic layer with water. Such washing operation was repeated 5 times. The organic layer after washing with water was concentrated. To the resulting concentrate, 107.71 parts of ethyl acetate was added and stirred until completely dissolved, and 646.26 parts of n-heptane was added dropwise. After completion of dropping, the mixture was stirred at 23 ° C. for 30 minutes and filtered to obtain 15.11 parts of a compound represented by the formula (MM).
MS (mass spectrometry): 486.2 (molecular ion peak)

Synthesis Example 2 (Synthesis of monomer (MN))
6.32 parts of the compound represented by the formula (N-2), 30.00 parts of tetrahydrofuran and 5.99 parts of pyridine were stirred and mixed at 23 ° C. for 30 minutes and cooled to 0 ° C. While maintaining the same temperature, 14.00 parts of the compound represented by formula (N-1) was added to the obtained mixture over 1 hour, and the temperature was further increased to about 10 ° C. Stir for 1 hour. To the reaction mixture containing the compound represented by the formula (N-3) obtained, the compound represented by the formula (N-4) (1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride) 14 .51 parts and 8.20 parts of the compound represented by the formula (N-5) were added and stirred at 23 ° C. for 3 hours. To the obtained reaction solution, 270 parts of ethyl acetate and 16.57 parts of 5% aqueous hydrochloric acid were added, and the mixture was stirred at 23 ° C. for 30 minutes. To the organic layer recovered by standing and separating, 65 parts of a saturated aqueous sodium hydrogen carbonate solution was added, stirred at 23 ° C. for 30 minutes, and allowed to stand and separate to wash the organic layer. Such washing operation was repeated twice. The organic layer after washing was charged with 65 parts of ion exchanged water, stirred at 23 ° C. for 30 minutes, allowed to stand, and separated to wash the organic layer with water. Such washing operation was repeated 5 times. The organic layer after washing with water was concentrated. The resulting concentrate is subjected to column fractionation (column fractionation conditions stationary phase: silica gel 60-200 mesh manufactured by Merck & Co., Ltd., developing solvent: n-heptane / ethyl acetate), and expressed by the formula (MN). 9.90 parts of compound were obtained.
MS (mass spectrometry): 434.1 (molecular ion peak)

Synthesis Example 3 (Synthesis of Monomer (MO))
25 parts of the compound represented by the formula (O-1) and 25 parts of tetrahydrofuran were charged, stirred and mixed at 23 ° C. for 30 minutes, and then cooled to 0 ° C. While maintaining the same temperature, a mixed solution of 8.5 parts of the compound represented by the formula (O-2), 11.2 parts of pyridine, and 25 parts of tetrahydrofuran was added to the obtained mixture over 1 hour. Furthermore, the temperature was raised to about 25 ° C., and the mixture was stirred at the same temperature for 1 hour. To the obtained reaction product, 190 parts of ethyl acetate and 50 parts of ion-exchanged water were added and stirred, followed by liquid separation to recover the organic layer. After the collected organic layer is concentrated, 150 parts of n-heptane is added to the resulting concentrate, and after stirring, the supernatant is removed and then concentrated to give a compound represented by the formula (O-3) 28.7 parts were obtained. The obtained compound (19.8 parts) represented by the formula (O-3), 90 parts of tetrahydrofuran, 10.3 parts of the compound represented by the formula (O-5) and 5.0 parts of pyridine were charged at 23 ° C. After stirring and mixing for 30 minutes, the mixture was cooled to 0 ° C. While maintaining the same temperature, 15.2 parts of a compound represented by the formula (O-4) (1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride) was added to the obtained mixture, and 23 Stir at 18 ° C. for 18 hours. To the obtained reaction solution, 450 parts of n-heptane and 47 parts of 5% hydrochloric acid aqueous solution were added and stirred at 23 ° C. for 30 minutes. 37 parts of 10% aqueous potassium carbonate solution was added to the organic layer recovered by standing and liquid separation, and the mixture was stirred at 23 ° C. for 30 minutes, and the organic layer was washed by standing and liquid separation. Such washing operation was repeated twice. To the organic layer after washing, 120 parts of ion-exchanged water was added, stirred at 23 ° C. for 30 minutes, allowed to stand, and separated to wash the organic layer with water. Such washing operation was repeated 5 times. The organic layer after washing with water was concentrated to obtain 20.1 parts of a compound represented by the formula (MO).
MS (mass spectrometry): 406.1 (molecular ion peak)

Synthesis Example 4 (Synthesis of monomer (M-K))
33.48 parts of the compound represented by the formula (K-1), 23.93 parts of dicyclohexylcarbodiimide and 40.00 parts of methylene chloride were charged into a reactor and mixed. After cooling the obtained mixture to about 0 ° C., 18.83 parts of the compound represented by the formula (K-2) was added, and the mixture was stirred for about 1 hour while maintaining about 0 ° C. The temperature was raised to 23 ° C., and the mixture was further stirred for 30 minutes. Insoluble matters were removed by filtration, and the obtained filtrate was concentrated to obtain 44.28 parts of a compound represented by the formula (K-3).

A reactor was charged with 19.42 parts of the compound represented by the formula (K-3) obtained as described above, 18.22 parts of the compound represented by the formula (K-4) and 200 parts of acetonitrile. Mixed. The resulting mixture was stirred at 50 ° C. for 3 hours. The obtained mixture was concentrated, 300 parts of chloroform and 150 parts of ion-exchanged water were added, and then the organic layer was recovered by a liquid separation operation. The recovered organic layer was washed with 150 parts of ion exchange water, and then the organic layer was concentrated. The concentrate is subjected to column fractionation (column fractionation conditions stationary phase: silica gel 60-200 mesh manufactured by Merck & Co., Ltd. developing solvent: ethyl acetate) to obtain 12.89 parts of a compound represented by the formula (M-K). It was.
MS (mass spectrometry): 308.1 (molecular ion peak)

Synthesis Example 5 (Synthesis of monomer (MP))
7.08 parts of the compound represented by the formula (P-2), 30.00 parts of tetrahydrofuran and 5.99 parts of pyridine were stirred and mixed at 23 ° C. for 30 minutes, and then cooled to 0 ° C. While maintaining the same temperature, 14.00 parts of the compound represented by the formula (P-1) was added to the obtained mixture over 1 hour, and the temperature was further increased to about 10 ° C. Stir for 1 hour. To the reaction mixture containing the compound represented by the formula (P-3) thus obtained, the compound (1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride) 14 represented by the formula (P-4) was added. .51 parts and 8.20 parts of the compound represented by the formula (P-5) were added and stirred at 23 ° C. for 3 hours. To the obtained reaction solution, 270 parts of ethyl acetate and 16.57 parts of 5% aqueous hydrochloric acid were added, and the mixture was stirred at 23 ° C. for 30 minutes. To the organic layer recovered by standing and separating, 65 parts of a saturated aqueous sodium hydrogen carbonate solution was added, stirred at 23 ° C. for 30 minutes, and allowed to stand and separate to wash the organic layer. Such washing operation was repeated twice. The organic layer after washing was charged with 65 parts of ion exchanged water, stirred at 23 ° C. for 30 minutes, allowed to stand, and separated to wash the organic layer with water. Such washing operation was repeated 5 times. The organic layer after washing with water was concentrated. The obtained concentrate is subjected to column fractionation (column fractionation conditions, stationary phase: silica gel 60-200 mesh manufactured by Merck & Co., Ltd., developing solvent: n-heptane / ethyl acetate), and expressed by the formula (MP). 10.24 parts of compound were obtained.
MS (mass spectrometry): 446.1 (molecular ion peak)

Synthesis Example 6 (Synthesis of Monomer (MQ))
6.32 parts of the compound represented by the formula (Q-2), 30.00 parts of tetrahydrofuran and 5.99 parts of pyridine were stirred and mixed at 23 ° C. for 30 minutes, and then cooled to 0 ° C. While maintaining the same temperature, 14.00 parts of the compound represented by the formula (Q-1) was added to the obtained mixture over 1 hour, and the temperature was further increased to about 10 ° C. Stir for 1 hour. To the reaction mixture containing the compound represented by the formula (Q-3) thus obtained, the compound represented by the formula (Q-4) (1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride) 14 .51 parts and 9.97 parts of the compound represented by the formula (Q-5) were added and stirred at 23 ° C. for 3 hours. To the obtained reaction solution, 300 parts of ethyl acetate and 16.57 parts of 5% aqueous hydrochloric acid were added, and the mixture was stirred at 23 ° C. for 30 minutes. To the organic layer recovered by standing and separating, 65 parts of a saturated aqueous sodium hydrogen carbonate solution was added, stirred at 23 ° C. for 30 minutes, and allowed to stand and separate to wash the organic layer. Such washing operation was repeated twice. The organic layer after washing was charged with 100 parts of ion-exchanged water, stirred at 23 ° C. for 30 minutes, allowed to stand, and separated to wash the organic layer with water. Such washing operation was repeated 5 times. The organic layer after washing with water was concentrated. The obtained concentrate is subjected to column fractionation (column fractionation conditions, stationary phase: silica gel 60-200 mesh, manufactured by Merck & Co., Ltd., developing solvent: n-heptane / ethyl acetate), and expressed by the formula (MQ). 19.85 parts of compound were obtained.
MS (mass spectrometry): 462.2 (molecular ion peak)

Synthesis Example 7 (Synthesis of salt represented by formula (B1-5))
The reactor was charged with 50.49 parts of the salt represented by the formula (B1-5-a) and 252.44 parts of chloroform, and stirred at 23 ° C. for 30 minutes. Thereafter, 16.27 parts of the compound represented by the formula (B1-5-b) is added dropwise thereto and stirred at 23 ° C. for 1 hour, whereby the salt represented by the formula (B1-5-c) is obtained. A solution containing was obtained. To the obtained solution containing the salt represented by the formula (B1-5-c), 48.80 parts of the salt represented by the formula (B1-5-d) and 84.15 parts of ion-exchanged water are added, The mixture was stirred at 23 ° C. for 12 hours. Since the resulting reaction solution was separated into two layers, the chloroform layer was separated and removed, and 84.15 parts of ion-exchanged water was further added to the chloroform layer and washed with water. This operation was repeated 5 times. To the obtained chloroform layer, 3.88 parts of activated carbon was added and stirred, followed by filtration. The collected filtrate was concentrated, 125.87 parts of acetonitrile was added to the resulting residue, and the mixture was stirred and concentrated. To the obtained residue, 20.62 parts of acetonitrile and 309.30 parts of tert-butyl methyl ether were added and stirred at 23 ° C. for 30 minutes, and then the supernatant was removed and concentrated. To the obtained residue, 200 parts of n-heptane was added, stirred at 23 ° C. for 30 minutes, and then filtered to obtain 61.54 parts of a salt represented by the formula (B1-5).
MASS (ESI (+) Spectrum): M ⁺ 375.2
MASS (ESI (−) Spectrum): M ^- 339.1

Synthesis of Resin (A) Compounds (monomers) used in the synthesis of resin (A) are shown below.
Hereinafter, these monomers are referred to as “monomer (MA)” to “monomer (M-R)” depending on their symbols.

[Synthesis of Resin A1-1]
The monomer (MM) was used as the 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 dissolved again in dioxane, and the resulting solution was poured into a methanol / water mixed solvent to precipitate the resin, and this resin was filtered twice, and the weight average molecular weight was 1.9. A 10 ⁴ resin A1-1 was obtained with a yield of 74%. This resin A1-1 has the following structural units.

[Synthesis of Resin A1-2]
A monomer (MN) 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 2.0. A 10 ⁴ resin A1-2 was obtained with a yield of 85%. This resin A1-2 has the following structural units.

[Synthesis of Resin A1-3]
Monomer (MO) was used as a monomer, and methyl isobutyl ketone 1.2 times the total monomer amount was added to prepare a solution. To this solution, 4.5 mol% of azobis (2,4-dimethylvaleronitrile) as an initiator was added with respect to the total monomer amount, and these were heated at 60 ° C. for about 5 hours. The obtained reaction mixture was poured into a large amount of n-heptane to precipitate a resin, and this resin was filtered to obtain a resin A1-3 having a weight average molecular weight of 3.9 × 10 ^{4 in} a yield of 90%. This resin A1-3 has the following structural units.

[Synthesis of Resin A1-4]
Monomers (MN) and monomers (MF) are used as monomers and mixed so that the molar ratio (monomer (MN): monomer (MF)) is 40:60. 1.2 mass times of methyl isobutyl ketone was added to make a solution. To this solution, 3 mol% of azobis (2,4-dimethylvaleronitrile) as an initiator was added with respect to the total monomer amount, and heated at 70 ° C. for about 5 hours. The obtained reaction mixture was poured into a large amount of a mixing solution of methanol / ion exchange water = 9/1 to precipitate a resin, and this resin was filtered to obtain a resin A1-4 having a weight average molecular weight of 8.3 × 10 ³ . (Copolymer) was obtained with a yield of 51%. This resin A1-4 has the following structural units.

[Synthesis of Resin A1-5]
Monomers (MN) and monomers (ME) are used as the monomers, and mixed so that the molar ratio (monomer (MN): monomer (ME)) is 40:60. 1.2 mass times of methyl isobutyl ketone was added to make a solution. To this solution, 3 mol% of azobis (2,4-dimethylvaleronitrile) as an initiator was added with respect to the total monomer amount, and heated at 70 ° C. for about 5 hours. The obtained reaction mixture was poured into a large amount of a mixing solution of methanol / ion exchange water = 9/1 to precipitate a resin, and this resin was filtered to obtain a resin A1-5 having a weight average molecular weight of 9.8 × 10 ³ . (Copolymer) was obtained with a yield of 79%. This resin A1-5 has the following structural units.

[Synthesis of Resin A1-6]
A monomer (MP) 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 dissolved again in dioxane, and the resulting solution was poured into a methanol / water mixed solvent to precipitate the resin, and this resin was filtered twice, and the weight average molecular weight was 1.9. A × 10 ⁴ resin A1-6 was obtained with a yield of 83%. This resin A1-6 has the following structural units.

[Synthesis of Resin A1-7]
Monomer (MQ) 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. × 10 ⁴ resin A1-7 was obtained with a yield of 76%. This resin A1-7 has the following structural units.

[Synthesis of Resin A2-1]
As a monomer, a monomer (MG), a monomer (ME), a monomer (MB), a monomer (M-H), and a monomer (M-K) are used, and the molar ratio (monomer (MG) : Monomer (ME): Monomer (MB): Monomer (M-H): Monomer (M-K)) were mixed so that the ratio was 32: 7: 8: 43: 10. 1.5 mass times dioxane was added 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 75 ° 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, 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 7.6. A × 10 ³ resin A2-1 (copolymer) was obtained with a yield of 80%. This resin A2-1 has the following structural units.

[Synthesis of Resin A2-2]
As a monomer, a monomer (MF), a monomer (M-I), a monomer (M-J), a monomer (MD) and a monomer (M-K) are used, and the molar ratio (monomer (MF)) : Monomer (M-I): monomer (M-J): monomer (MD): monomer (M-K)) were mixed so that 45: 14: 2.5: 22.5: 16, Dioxane of 1.5 mass times the total monomer amount was added 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, 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 8.8. A × 10 ³ resin A2-2 (copolymer) was obtained in a yield of 71%. This resin A2-2 has the following structural units.

[Synthesis of Resin A2-3]
As a monomer, a monomer (M−F), a monomer (M−I), a monomer (M−J), a monomer (M−D), a monomer (M−H), and a monomer (M−K) are used, and a molar ratio thereof. (Monomer (MF): Monomer (M-I): Monomer (M-J): Monomer (MD): Monomer (M-H): Monomer (M-K))) 45: 14: 2. It mixed so that it might become 5: 17.5: 5: 16, and the dioxane of 1.5 mass times the total monomer amount was added, and it was set as the 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 75 ° 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, 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 8.3. A × 10 ³ resin A2-3 (copolymer) was obtained in a yield of 69%. This resin A2-3 has the following structural units.

[Synthesis of Resin A2-4]
As the monomer, the monomer (MF), the monomer (MR), the monomer (MJ), the monomer (MD) and the monomer (MK) are used, and the molar ratio [monomer (MF) : Monomer (M-R): monomer (M-J): monomer (MD): monomer (M-K)] is mixed to be 45: 14: 2.5: 22.5: 16, A solution was prepared by adding propylene glycol monomethyl ether acetate of 1.5 mass times the total monomer amount. 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 75 ° 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 again dissolved in propylene glycol monomethyl ether acetate, and the resulting solution was poured into a methanol / water mixed solvent to precipitate the resin, followed by reprecipitation operation of filtering the resin twice. Resin A2-4 (copolymer) having a molecular weight of 8.2 × 10 ³ was obtained in a yield of 66%. This resin A2-4 has the following structural units.

[Synthesis of Resin A2-5]
As a monomer, a monomer (MG), a monomer (MR), a monomer (MB), a monomer (M-H) and a monomer (M-K) are used, and the molar ratio [monomer (MG) : Monomer (MR): monomer (MB): monomer (M-H): monomer (M-K)] to be 32: 7: 8: 43: 10 1.5 mass times propylene glycol monomethyl ether acetate was added to prepare 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 75 ° 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 again dissolved in propylene glycol monomethyl ether acetate, and the resulting solution was poured into a methanol / water mixed solvent to precipitate the resin, followed by reprecipitation operation of filtering the resin twice. Resin A2-5 (copolymer) having a molecular weight of 7.9 × 10 ³ was obtained in a yield of 82%. This resin A2-5 has the following structural units.

[Synthesis of Resin X1]
Monomer (MA) and monomer (MC) are used as monomers and mixed so that the molar ratio (monomer (MA): monomer (MC)) is 40:60. An amount of 1.5 mass times dioxane was added to prepare a solution. To this solution, azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added in an amount of 1.4 mol% and 4.2 mol%, respectively, based on the total monomer amount, and these were added at 70 ° 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 dissolved again in dioxane, and the resulting solution was poured into a methanol / water mixed solvent to precipitate the resin, and the reprecipitation operation of filtering the resin was performed twice, and the weight average molecular weight was 5.0. A × 10 ³ resin X1 (copolymer) was obtained in a yield of 92%. This resin X1 has the following structural units.

[Synthesis of Resin X2]
As a monomer, a monomer (M-A), a monomer (M-H), and a monomer (M-B) are used, and the molar ratio (monomer (M-A): monomer (M-H): monomer (M-B)). ) Was 35:45:20, and 1.5 mass times dioxane of the total monomer amount was added to prepare a solution. To this solution, azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added in an amount of 1.0 mol% and 3.0 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 dissolved again 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 7.0. A × 10 ³ resin X2 (copolymer) was obtained in a yield of 75%. This resin X2 has the following structural units.

[Synthesis of Resin X3]
Monomer (ML) and monomer (MA) are used as monomers and mixed so that the molar ratio (monomer (ML): monomer (MA)) is 80:20. An amount of 1.5 mass times dioxane was added to prepare a solution. To this solution, azobisisobutyronitrile and azobis (2,4-dimethylvaleronitrile) as initiators were added in an amount of 0.5 mol% and 1.5 mol%, respectively, based on the total monomer amount, and these were added at 70 ° 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 2.8. A × 10 ⁴ resin X3 (copolymer) was obtained in a yield of 70%. This resin X3 has the following structural units.

<Preparation of resist composition>
Each of the components shown below was dissolved in a solvent in parts by mass shown in Table 1, and further filtered through a fluororesin filter having a pore size of 0.2 μm to prepare a resist composition.

<Resin>
Resins A1-1 to A1-7, A2-1 to A2-5, X1 to X3 synthesized in the synthesis examples described above
<Acid generator>
B1-3: synthesized according to the example of JP 2010-152341 A
B1-5:
B2: Triphenylsulfonium triflate (manufactured by TPS-105 Midori Chemical Co., Ltd.)
B3: synthesized according to the example of WO2008 / 99869 and the example of JP2010-26478A
B4: Synthesis according to the example of JP-A-2005-221721

<Basic compound: Quencher>
C1: 2,6-diisopropylaniline (manufactured by Tokyo Chemical Industry Co., Ltd.)

<Solvent>
Propylene glycol monomethyl ether acetate 265 parts Propylene glycol monomethyl ether 20 parts 2-heptanone 20 parts γ-butyrolactone 3.5 parts

Examples 1-15 and Comparative Examples 1-2
<Manufacture of negative resist pattern>
An organic antireflective coating composition [ARC-29; manufactured by Nissan Chemical Industries, Ltd.] was applied onto a 12-inch silicon wafer, and baked under the conditions of 205 ° C. and 60 seconds, whereby an organic layer having a thickness of 78 nm was obtained. An antireflection film was formed. Next, the resist composition was spin-coated on the organic antireflection film so that the film thickness of the composition layer after drying (pre-baking) was 100 nm. After coating, the composition layer was formed on the silicon wafer by pre-baking on a direct hot plate for 60 seconds at the temperature described in the “PB” column of Table 1. ArF excimer laser stepper for immersion exposure [XT: 1900 Gi; manufactured by ASML, NA = 1.35, Annual σ _out = 0.85 σ _in = 0.65 XY-pol on a silicon wafer on which the composition layer is formed . Illumination], using a mask for forming a trench pattern (pitch 120 nm / trench width 40 nm), the exposure amount was changed stepwise to perform exposure. Note that ultrapure water was used as the immersion medium. After the exposure, post-exposure baking was performed for 60 seconds on the hot plate at the temperature described in the “PEB” column of Table 1. Next, the composition layer on the silicon wafer was subjected to dynamic dispense development at 23 ° C. for 20 seconds using butyl acetate (manufactured by Tokyo Chemical Industry Co., Ltd.) as a developer, thereby producing a negative resist pattern. .

  In the obtained resist pattern, the exposure amount at which the width of the trench pattern was 40 nm was defined as effective sensitivity.

<Line edge roughness evaluation (LER)>
The side wall of the obtained resist pattern is observed with a scanning electron microscope, and the fluctuation width of the unevenness on the side wall is
○ that is 5 nm or less,
The thing exceeding 5 nm was set as x.
The results are shown in Table 2. The numerical value in the parenthesis represents the fluctuation width (nm).

<Defect evaluation>
An organic antireflective coating composition [ARC-29; manufactured by Nissan Chemical Industries, Ltd.] was applied onto a 12-inch silicon wafer, and baked under the conditions of 205 ° C. and 60 seconds, whereby an organic layer having a thickness of 78 nm was obtained. An antireflection film was formed. Subsequently, the resist composition was spin-coated on the organic antireflection film so that the film thickness of the composition layer was 100 nm after drying (prebaking). After the application, this silicon wafer was pre-baked on a direct hot plate at a temperature described in the “PB” column of Table 1 for 60 seconds to form a composition layer on the silicon wafer.
An ArF excimer laser stepper for immersion exposure (XT: 1900 Gi; manufactured by ASML, NA = 1.35, 3/4 Annular XY polarized illumination) is applied to the silicon wafer on which the composition layer is formed at a 1: 1 line and Using a mask for forming a space pattern (pitch 80 nm), exposure was performed with an exposure amount at which the line width and space width of the obtained line-and-space pattern were 1: 1. Note that ultrapure water was used as the immersion medium. After the exposure, post-exposure baking was performed for 60 seconds on the hot plate at the temperature described in the “PEB” column of Table 1. Next, the composition layer on the silicon wafer was subjected to dynamic dispense development at 23 ° C. for 20 seconds using butyl acetate (manufactured by Tokyo Chemical Industry Co., Ltd.) as a developer, thereby producing a negative resist pattern. .
Thereafter, the number of defects on the line pattern on the wafer was measured using a defect inspection apparatus [KLA-2360; manufactured by KLA Tencor]. The results are shown in Table 2.

Examples 16 to 30 and Comparative Examples 3 and 4
Except for changing the developer to 2-heptanone (manufactured by Kyowa Hakko Co., Ltd.), the same operation as above was performed to produce a negative resist pattern, and the same evaluation as in the examples was performed. The results are shown in Table 3.

  From the above results, it can be seen that the resist composition of the present invention can produce a negative resist pattern with excellent line edge roughness and few defects.

<Preparation of resist composition>
Each of the components shown below was dissolved in the following solvent in the parts by mass shown in Table 4 and further filtered through a fluororesin filter having a pore size of 0.2 μm to prepare a resist composition.

Examples 31-35 and Comparative Examples 5-6
<Manufacture of resist pattern>
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 (pre-baking) 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 4. Using the ArF excimer stepper for immersion exposure [XT: 1900Gi; manufactured by ASML, NA = 1.35, 3/4 Annular XY polarized light] on the wafer on which the resist composition film is formed in this manner, the exposure amount is stepwise. The line and space pattern was subjected to immersion exposure. Note that ultrapure water was used as the immersion medium.
After the exposure, post-exposure baking (PEB) was performed for 60 seconds on a hot plate at the temperature described in the “PEB” column of Table 4, and then with an aqueous 2.38 mass% tetramethylammonium hydroxide solution for 60 seconds. Paddle development was performed to obtain a resist pattern.

  In each of the obtained resist pattern films, an exposure amount at which the 50 nm line and space pattern becomes an exposure amount of 1: 1 was defined as an 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 fluctuation width (nm) of the unevenness on the side wall of the resist pattern was obtained. This swing is
○ that is 4 nm or less,
What exceeded 4 nm was set as x.
The results are shown in Table 5.

<Defect evaluation>
The resist composition was applied (spin coated) to a 12-inch silicon wafer (substrate) so that the film thickness after drying was 0.15 μm. After coating, the composition layer was formed on the wafer by pre-baking (PB) for 60 seconds at a temperature shown in the PB column of Table 4 on a direct hot plate.
The wafer on which the composition layer was formed in this manner was subjected to water rinsing for 60 seconds using a developing machine [ACT-12; manufactured by Tokyo Electron Ltd.].
Thereafter, the number of defects on the wafer was measured using a defect inspection apparatus [KLA-2360; manufactured by KLA Tencor]. The results are shown in Table 5.

  Since the resist composition of the present invention can produce a resist pattern with good line edge roughness (LER) and defects, it can be used for fine processing of semiconductors.

Claims (3)

(A1) a resin having a structural unit represented by formula (I),
(A2) A resin comprising a structural unit represented by formula (II), a structural unit having an acid labile group, and a structural unit having an adamantane ring substituted with two hydroxy groups represented by formula (a2-1) As well as
(B) A resist composition containing an acid generator.
[In the formula (I),
R ¹ represents a hydrogen atom or a methyl group.
A ¹ represents an alkanediyl group having 1 to 6 carbon atoms.
A ¹³ represents a C 1-6 perfluoroalkanediyl group.
X ¹² represents * —CO—O— or * —O—CO—, and * represents a bond to A ¹³ .
A ¹⁴ represents an aliphatic hydrocarbon group having 1 to 17 carbon atoms which may have a halogen atom. ]
[In the formula (II),
R ²¹ represents an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, a hydrogen atom or a halogen atom.
A ²¹ represents a single ^{bond, * -A 22 -O-, * -A} 22 -CO-O-, * -A 22 -CO-O-A 23 -CO-O- or ^* -A ²² -O-CO -A ²³ represent a -O-.
* Represents a bond with -O-.
A ²² and A ²³ each independently represents an alkanediyl group having 1 to 6 carbon atoms. ]
[In the formula (a2-1),
L ^a3 represents —O— or ^* —O— (CH ₂ ) _k2 —CO—O—,
k2 represents an integer of 1 to 7. * Represents a bond with -CO-.
R ^a14 represents a hydrogen atom or a methyl group.
R ^a15 and R ^a16 each independently represents a hydrogen atom, a methyl group or a hydroxy group, one of R ^a15 and R ^a16 represents a hydroxy group, and the other represents a hydrogen atom or a methyl group.
o1 represents an integer of 0 to 10. ]   Furthermore, the resist composition of Claim 1 containing a solvent. (1) The process of apply | coating the resist composition of Claim 1 or 2 on a board | substrate,
(2) The process of drying the composition after application | coating and forming a composition layer,
(3) a step of exposing the composition layer,
(4) A method for producing a resist pattern, comprising: a step of heating the composition layer after exposure; and (5) a step of developing the composition layer after heating.