Resist lower layer film-forming composition, polymer, resist lower layer film, pattern-forming method, and method of producing semiconductor device

1. A resist lower layer film-forming composition comprising:

(A) a polymer including:

a structural unit (I) shown by a formula (1); and

a structural unit (II) shown by a formula (2); and

(B) a crosslinking agent including at least two crosslinkable functional groups,

wherein R 1 represents a hydrogen atom, a halogen atom, a methyl group, or a trifluoromethyl group, Q 1 represents a divalent linking group, Y represents a single bond, a methylene group, a linear or branched alkylene group having 2 to 10 carbon atoms, an arylene group having 6 to 20 carbon atoms, a 6 to 20-membered heteroarylene group, or a combination thereof, provided that some or all of the hydrogen atoms of the alkylene group, the arylene group, or the heteroarylene group may be substituted with a substituent, and the alkylene group may include an oxygen atom in its carbon chain, p is an integer from 0 to 3, q is 0 or 1, r is an integer from 0 to 2, and X represents —CH 2 —, —CH, —CH 2 —, —O—, —S—, or —SO 2 —, provided that a plurality of X may be either the same or different when r is 2,

wherein R 2 represents a hydrogen atom, a halogen atom, a methyl group, or a trifluoromethyl group, Q 2 represents a divalent linking group, R 3 represents an aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, or a 6 to 20-membered heteroaryl group, provided that some or all of the hydrogen atoms of the aryl group, the aralkyl group, or the heteroaryl group may be substituted with a substituent.

2. The resist lower layer film-forming composition according to claim 1 , wherein the polymer (A) includes a structural unit shown by a formula (1-1) as the structural unit (I), and further includes a structural unit (II-1) shown by a formula (2-1),

wherein R 1 , X, Y, p, q, and r are the same as defined for the formula (1), R 4 represents a hydrogen atom, a halogen atom, a methyl group, or a trifluoromethyl group, and R 6 represents an alkyl group having 1 to 15 carbon atoms or an aryl group having 6 to 20 carbon atoms, provided that some or all of the hydrogen atoms of the alkyl group or the aryl group are substituted with a substituent, at least one substituent being a group that includes a hydroxyl group or an amino group.

3. The resist lower layer film-forming composition according to claim 2 , wherein R 6 represents the aryl group.

4. The resist lower layer film-forming composition according to claim 1 , wherein the polymer (A) further includes a structural unit (III) that includes a fluorine atom.

5. The resist lower layer film-forming composition according to claim 1 , wherein the structural unit (II) is a structural unit (II-2) shown by a formula (2-2),

wherein R 5 represents a hydrogen atom, a halogen atom, a methyl group, or a trifluoromethyl group, and R 7 represents a phenyl group, a naphthyl group, an anthryl group, or a linear or branched alkyl group having 1 to 15 carbon atoms, provided that some or all of the hydrogen atoms of the phenyl group, the naphthyl group, or the anthryl group may be substituted with a substituent other than a hydroxyl group and an amino group, and some or all of the hydrogen atoms of the alkyl group are substituted with a substituent, at least one substituent being a phenyl group, a naphthyl group, or an anthryl group, provided that some or all of the hydrogen atoms of the phenyl group, the naphthyl group, or the anthryl group may be substituted with a substituent other than a hydroxyl group and an amino group.

6. The resist lower layer film-forming composition according to claim 1 , wherein the structural unit (II) is a structural unit shown by a formula (2-2-1), a formula (2-2-2), a formula (2-2-3), a formula (2-2-4), a formula (2-2-5), or a combination thereof,

wherein R 2 is the same as defined for the formula (2).

7. A polymer comprising a structural unit (I) shown by a formula (1-1), a structural unit (II-1) shown by a formula (2-1), and a structural unit (II-2) shown by a formula (2-2),

wherein R 1 , X, Y, p, q, and r are the same as defined for the formula (1), R 4 represents a hydrogen atom, a halogen atom, a methyl group, or a trifluoromethyl group, R 6 represents an alkyl group having 1 to 15 carbon atoms or an aryl group having 6 to 20 carbon atoms, provided that some or all of the hydrogen atoms of the alkyl group or the aryl group are substituted with a substituent, at least one substituent being a group that includes a hydroxyl group or an amino group, R 5 represents a hydrogen atom, a halogen atom, a methyl group, or a trifluoromethyl group, and R 7 represents a phenyl group, a naphthyl group, an anthryl group, or a linear or branched alkyl group having 1 to 15 carbon atoms, provided that some or all of the hydrogen atoms of the phenyl group, the naphthyl group, or the anthryl group may be substituted with a substituent other than a hydroxyl group and an amino group, and some or all of the hydrogen atoms of the alkyl group are substituted with a substituent, at least one substituent being a phenyl group, a naphthyl group, or an anthryl group, provided that some or all of the hydrogen atoms of the phenyl group, the naphthyl group, or the anthryl group may be substituted with a substituent other than a hydroxyl group and an amino group.

8. A resist lower layer film formed using the resist lower layer film-forming composition according to claim 1 .

9. A pattern-forming method comprising:

(1) applying the resist lower layer film-forming composition according to claim 1 to a substrate to form a resist lower layer film;

(2) applying a resist composition to the resist lower layer film to form a resist film;

(3) exposing the resist film by selectively applying radiation to the resist film via a photomask;

(4) developing the exposed resist film to form a resist pattern; and

(5) dry-etching the resist lower layer film and the substrate using the resist pattern as a mask to form a pattern.

10. The pattern-forming method according to claim 9 , wherein the resist film is exposed by applying light having a wavelength of 193 nm to the resist film.

11. A method of producing a semiconductor device comprising:

(1) applying the resist lower layer film-forming composition according to claim 1 to a substrate to form a resist lower layer film;

(2) applying a resist composition to the resist lower layer film to form a resist film;

(3) exposing the resist film by selectively applying radiation to the resist film via a photomask;

(4) developing the exposed resist film to form a resist pattern;

(5) dry-etching the resist lower layer film and the substrate using the resist pattern as a mask to form a pattern; and

(6) forming an integrated circuit element that includes the pattern.

12. The method of producing a semiconductor device according to claim 11 , wherein the resist film is exposed by applying light having a wavelength of 193 nm to the resist film.