Resist pattern-forming method

1. A resist pattern-forming method comprising:

applying a resist underlayer film-forming composition to a substrate to form a resist underlayer film, the resist underlayer film-forming composition including (A) a polysiloxane;

applying a radiation-sensitive resin composition to the resist underlayer film to form a resist film, the radiation-sensitive resin composition including (a1) a polymer that changes in polarity and decreases in solubility in an organic solvent due to an acid;

exposing the resist film; and

developing the exposed resist film using a developer that includes an organic solvent, wherein the polysiloxane (A) is a hydrolysis-condensation product of a silane compound shown by a formula (i),

R A a SiX 4-a   (i)

wherein R A represents a hydrogen atom, a fluorine atom, an alkyl group having 1 to 5 carbon atoms, an alkenyl group, an aryl group, or a cyano group; the alkyl group represented by R A is unsubstituted, or at least one hydrogen atom of the alkyl group represented by R A is substituted with a glycidyloxy group, an oxetanyl group, an acid anhydride group, or a cyano group; the aryl group represented by R A is unsubstituted, or at least one hydrogen atom of the aryl group represented by R A is substituted with a hydroxyl group; X represents a halogen atom or —OR B , wherein R B represents a monovalent organic group; a is an integer from 0 to 3;

in a case where a plurality of R A are present, each of the plurality of R A is either identical or different; and in a case where plurality of X are present, each of the plurality of X is either identical or different.

2. The resist pattern-forming method according to claim 1 , wherein the resist underlayer film-forming composition further includes (B) a nitrogen-containing compound.

3. The resist pattern-forming method according to claim 1 , wherein the resist underlayer film-forming composition further includes (C) a photoacid generator.

4. The resist pattern-forming method according to claim 1 , wherein the polymer (a1) includes a structural unit (I) shown by a formula (1),

wherein R represents a hydrogen atom or a methyl group; and each of R p1 , R p2 , and R p3 individually represents a monovalent hydrocarbon group having 1 to 20 carbon atoms; or R p1 represents a monovalent hydrocarbon group having 1 to 20 carbon atoms, and R p2 and R p3 bond to each other to form a divalent alicyclic hydrocarbon group having 4 to 20 carbon atoms together with a carbon atom bonded to R p2 and R p3 .

5. The resist pattern-forming method according to claim 1 , wherein the radiation-sensitive resin composition further includes (a2) a polymer that includes a structural unit shown by a formula (3-1), a structural unit shown by a formula (3-2) or both thereof,

wherein R 1 represents a hydrogen atom, a methyl group, or a trifluoromethyl group, and R 2 represents a linear or branched alkyl group having 1 to 6 carbon atoms that includes a fluorine atom, or a monovalent alicyclic group having 4 to 20 carbon atoms that includes a fluorine atom, wherein the alkyl group represented by R 2 is unsubstituted or at least one hydrogen atom of the alkyl group represented by R 2 is substituted with a substituent, and wherein the alicyclic hydrocarbon group represented by R 2 is unsubstituted or at least one hydrogen atom of the alicyclic hydrocarbon group represented by R 2 is substituted with a substituent,

wherein R 3 represents a hydrogen atom, a methyl group, or a trifluoromethyl group, R 4 represents an (m+1)-valent linking group, m is an integer from 1 to 3, X represents a divalent linking group that includes a fluorine atom, and R 5 represents a hydrogen atom or a monovalent organic group, and wherein, in a case where m is 2 or 3, each of a plurality of X is either identical or different and each of a plurality of R 5 is either identical or different.

6. The resist pattern-forming method according to claim 5 , wherein the polymer (a2) does not include an acid-labile group.

7. The resist pattern-forming method according claim 1 , the resist pattern-forming method being used to form a trench pattern, a hole pattern or both thereof.

8. A resist pattern-forming method comprising:

applying a resist underlayer film-forming composition to a substrate to form a resist underlayer film, the resist underlayer film-forming composition including (A) a polysiloxane consisting essentially of siloxane repeat units;

applying a radiation-sensitive resin composition to the resist underlayer film to form a resist film, the radiation-sensitive resin composition including (a1) a polymer that changes in polarity and decreases in solubility in an organic solvent due to an acid;

exposing the resist film; and

developing the exposed resist film using a developer that includes an organic solvent.

9. The resist pattern-forming method according to claim 8 , wherein the polysiloxane (A) is a hydrolysis-condensation product of a silane compound shown by a formula (i),

R A a SiX 4-a   (i)

wherein R A represents a hydrogen atom, a fluorine atom, an alkyl group having 1 to 5 carbon atoms, an alkenyl group, an aryl group, or a cyano group; the alkyl group represented by R A is unsubstituted, or at least one hydrogen atom of the alkyl group represented by R A is substituted with a glycidyloxy group, an oxetanyl group, an acid anhydride group, or a cyano group; the aryl group represented by R A is unsubstituted, or at least one hydrogen atom of the aryl group represented by R A is substituted with a hydroxyl group; X represents a halogen atom or —OR B , wherein R B represents a monovalent organic group; a is an integer from 0 to 3;

in a case where a plurality of R A are present, each of the plurality of R A is either identical or different; and in a case where plurality of X are present, each of the plurality of X is either identical or different.