RADIATION-SENSITIVE RESIN COMPOSITION, METHOD OF FORMING RESIST PATTERN, AND POLYMER

1 . A radiation-sensitive resin composition comprising:

a polymer comprising a first structural unit represented by formula (1), solubility of the polymer in a developer solution being capable of being altered by an action of an acid; and

a compound represented by formula (2):

wherein,

in the formula (1),

R 1 represents a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group;

R 2 represents a group obtained by removing, from a substituted or unsubstituted aliphatic hydrocarbon ring having 3 to 30 ring atoms, two hydrogen atoms which bond to one carbon atom; and

Ar 1 represents a group obtained by removing one hydrogen atom from a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 30 ring atoms, and

in the formula (2),

Z represents an acid-labile group;

L 1 represents *—O—CO— or —O—, wherein * denotes a site bonding to Z;

Y represents an organic group having 1 to 30 carbon atoms and having a valency of (n+1), the organic group not comprising a cyclic acetal structure;

A − represents a monovalent anion group;

n is an integer of 1 to 5, wherein in a case in which n is no less than 2, two or more Zs are identical or different from each other, and two or more L 1 s are identical or different from each other; and

X + represents a monovalent radiation-sensitive onium cation.

2 . The radiation-sensitive resin composition according to claim 1 , wherein A − in the formula (2) represents SO 3 − ; or COO − .

3 . The radiation-sensitive resin composition according to claim 1 , wherein A − in the formula (2) represents SO 3 − .

4 . The radiation-sensitive resin composition according to claim 1 , wherein Y in the formula (2) comprises, as a ring structure, only an aliphatic hydrocarbon ring, an aromatic hydrocarbon ring, an aromatic heterocyclic ring, or a combination thereof.

5 . The radiation-sensitive resin composition according to claim 1 , wherein the polymer further comprises a second structural unit represented by formula (3-1):

wherein, in the formula (3-1),

R 3 represents a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group;

L 2 represents a single bond, —COO—, —O—, or —CONH—;

Ar 2 represents a group obtained by removing (s+t+1) hydrogen atoms from an aromatic hydrocarbon ring having 6 to 30 ring atoms;

s is an integer of 1 to 3; and

t is an integer of 0 to 8, wherein

in a case in which tis 1, R 4 represents a halogen atom or a monovalent organic group having 1 to 20 carbon atoms, and

in a case in which t is no less than 2, a plurality of R 4 s are identical or different from each other, and each R 4 represents a halogen atom or a monovalent organic group having 1 to 20 carbon atoms, or two or more of the plurality of R 4 s taken together represent an aliphatic ring having 4 to 20 ring atoms together with the carbon chain to which the two or more of the plurality of R 4 s bond.

6 . The radiation-sensitive resin composition according to claim 4 , wherein, in the formula (3-1),

in a case in which s is 1, the hydroxy group bonds to, of the carbon atoms constituting Ar 2 , the carbon atom adjacent to the carbon atom which bonds to L 2 , and

in a case in which s is no less than 2, at least one of the hydroxy groups bonds to, of the carbon atoms constituting Ar 2 , the carbon atom adjacent to the carbon atom which bonds to L 2 .

7 . A radiation-sensitive resin composition comprising:

a polymer comprising: a first structural unit represented by formula (1); and a third structural unit represented by formula (3-2), solubility of the polymer in a developer solution being capable of being altered by an action of an acid; and

a radiation-sensitive acid generating agent,

wherein,

in the formula (1),

R 1 represents a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group;

R 2 represents a group obtained by removing, from a substituted or unsubstituted aliphatic hydrocarbon ring having 3 to 30 ring atoms, two hydrogen atoms which bond to one carbon atom; and

Ar 1 represents a group obtained by removing one hydrogen atom from a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 30 ring atoms, and

in the formula (3-2),

R 3 represents a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group;

L 2 represents a single bond, —COO—, —O—, or —CONH—;

Ar 2 represents a group obtained by removing (s+t+1) hydrogen atoms from an aromatic hydrocarbon ring having 6 to 30 ring atoms;

s is an integer of 1 to 3, wherein

in a case in which s is 1, the hydroxy group bonds to, of the carbon atoms constituting Ar 2 , the carbon atom adjacent to the carbon atom which bonds to L 2 , and

in a case in which s is no less than 2, at least one of the hydroxy groups bonds to, of the carbon atoms constituting Ar 2 , the carbon atom adjacent to the carbon atom which bonds to L 2 ; and

t is an integer of 0 to 8, wherein

in a case in which tis 1, R 4 represents a halogen atom or a monovalent organic group having 1 to 20 carbon atoms, and

in a case in which t is no less than 2, a plurality of R 4 s are identical or different from each other, and each R 4 represents a halogen atom or a monovalent organic group having 1 to 20 carbon atoms, or two or more of the plurality of R 4 s taken together represent an aliphatic ring having 4 to 20 ring atoms together with the carbon chain to which the two or more of the plurality of R 4 s bond.

8 . A method of forming a resist pattern, the method comprising:

applying the radiation-sensitive resin composition according to claim 1 directly or indirectly on a substrate to form a resist film;

exposing the resist film; and

developing the resist film exposed.

9 . A method of forming a resist pattern, the method comprising:

applying the radiation-sensitive resin composition according to claim 7 directly or indirectly on a substrate to form a resist film;

exposing the resist film; and

developing the resist film exposed.

10 . A polymer comprising:

a first structural unit represented by formula (1); and

a third structural unit represented by formula (3-2):

wherein,

in the formula (1),

R 1 represents a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group;

R 2 represents a group obtained by removing, from a substituted or unsubstituted aliphatic hydrocarbon ring having 3 to 30 ring atoms, two hydrogen atoms which bond to one carbon atom; and

Ar 1 represents a group obtained by removing one hydrogen atom from a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 30 ring atoms, and

in the formula (3-2),

R 3 represents a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group;

L 2 represents a single bond, —COO—, —O—, or —CONH—;

Ar 2 represents a group obtained by removing (s+t+1) hydrogen atoms from an aromatic hydrocarbon ring having 6 to 30 ring atoms;

s is an integer of 1 to 3, wherein

in a case in which s is 1, the hydroxy group bonds to, of the carbon atoms constituting Ar 2 , the carbon atom adjacent to the carbon atom which bonds to L 2 , and

in a case in which s is no less than 2, at least one of the hydroxy groups bonds to, of the carbon atoms constituting Ar 2 , the carbon atom adjacent to the carbon atom which bonds to L 2 ; and

t is an integer of 0 to 8, wherein

in a case in which t is 1, R 4 represents a halogen atom or a monovalent organic group having 1 to 10 carbon atoms, and

in a case in which t is no less than 2, a plurality of R 4 s are identical or different from each other, and each R 4 represents a halogen atom or a monovalent organic group having 1 to 10 carbon atoms, or two or more of the plurality of R 4 s taken together represent an aliphatic ring having 4 to 20 ring atoms together with the carbon chain to which the two or more of the plurality of R 4 s bond.