Composition for forming resist underlayer film and method for forming pattern
A resist underlayer film-forming composition includes (A) a polymer that includes a repeating unit shown by a formula (1), and has a polystyrene-reduced weight average molecular weight of 3000 to 10,000, and (B) a solvent, wherein R 3 to R 8 individually represent a group shown by the following formula (2) or the like, —O—R 1 ≡R 2 (2) wherein R 1 represents a single bond or the like, and R 2 represents a hydrogen atom or the like.
1. A method for forming a pattern comprising:
applying a resist underlayer film-forming composition to a substrate to form a resist underlayer film,
applying a resist composition to the substrate to form a resist film,
exposing the resist film by selectively applying radiation to the resist film via a photomask,
developing the exposed resist film to form a resist pattern, and
dry-etching the resist underlayer film and the substrate using the resist pattern as a mask to form a pattern,
wherein the resist underlayer film-forming composition comprises:
(A) a polymer that includes a repeating unit shown by a formula (1), and has a polystyrene-reduced weight average molecular weight of 3000 to 10,000; and
(B) a solvent,
wherein R 3 to R 8 individually represent a group shown by a formula (2), a hydrogen atom, a hydroxyl group, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, a substituted or unsubstituted alkoxycarbonyl group having 2 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 14 carbon atoms, or a substituted or unsubstituted glycidyl ether group having 2 to 6 carbon atoms, provided that at least one of R 3 to R 8 represents the group shown by the formula (2), and X represents a substituted or unsubstituted alkanediyl group having 1 to 10 carbon atoms, a substituted or unsubstituted cycloalkanediyl group having 3 to 20 carbon atoms, a substituted or unsubstituted alkanediyloxy group having 1 to 10 carbon atoms, a substituted or unsubstituted cycloalkanediyloxy group having 3 to 20 carbon atoms, a substituted or unsubstituted arylene group having 6 to 14 carbon atoms, or a divalent group formed by combining arbitrary groups among these groups,
—O—R 1 ≡R 2 (2)
wherein R 1 represents a single bond, a substituted or unsubstituted alkanediyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted arylene group having 6 to 20 carbon atoms, and R 2 represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms.
2. The method according to claim 1 , wherein the polymer (A) has a dispersity of 1.4 to 5.0.
3. The method according to claim 1 , wherein the resist underlayer film-forming composition further comprises (C) an acid generator.
4. The method according to claim 1 , wherein the resist underlayer film-forming composition further comprises (D) a crosslinking agent.