Composition for forming resist underlayer film, and pattern-forming method

1. A pattern-forming method comprising:

providing a resist underlayer film on a substrate using a resist underlayer film composition;

providing a resist film on the resist underlayer film using a resist composition;

exposing the resist film by irradiation with an exposure light through a photomask;

developing the exposed resist film to form a resist pattern; and

sequentially dry-etching the resist underlayer film and the substrate using the resist pattern as a mask,

wherein the resist underlayer film composition comprises:

a polysiloxane;

an acid diffusion control agent; and

an organic solvent composition comprising:

an alkylene glycol monoalkyl ether acetate having a standard boiling point of less than 150.0° C.; and

an organic solvent which is an ester, an ether or a combination thereof and which has a standard boiling point of no less than 180° C.,

wherein in the organic solvent composition, a content of the alkylene glycol monoalkyl ether acetate is no less than 50% by mass and no greater than 99% by mass, and a content of the organic solvent is no less than 1% by mass and no greater than 50% by mass.

2. The pattern-forming method according to claim 1 , wherein the organic solvent is a carboxylate ester, a lactone, a carbonate, a compound represented by formula (1), or a combination thereof:

wherein, in the formula (1), R 1 and R 2 each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or an acyl group having 1 to 4 carbon atoms; R 3 represents a hydrogen atom or a methyl group; n is an integer of 1 to 4, wherein in a case where n is 2 or greater, a plurality of R 3 s are each a same or different.

3. The pattern-forming method according to claim 1 , wherein a relative permittivity of the organic solvent is 13 or greater and 200 or less.

4. The pattern-forming method according to claim 1 , wherein the alkylene glycol monoalkyl ether acetate is a propylene glycol monoalkyl ether acetate.

5. The pattern-forming method according to claim 1 , wherein the polysiloxane is a hydrolytic condensate of a compound comprising a silane compound represented by formula (i):

R A a SiX 4-a   (i)

wherein, in the formula (i), R A represents a hydrogen atom, a fluorine atom, an alkyl group having 1 to 5 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 20 carbon atoms or a cyano group, wherein a part or all of hydrogen atoms of the alkyl group represented by R A are not substituted or substituted by an epoxyalkyloxy group, an epoxy group, an acid anhydride group or a cyano group, and a part or all of hydrogen atoms of the aryl group represented by R A are not substituted or substituted by a hydroxy group; X represents a halogen atom or —OR B , wherein R B represents a monovalent organic group; a is an integer of 0 to 3, wherein in a case where R A and X are each present in a plurality of number, a plurality of R A s are each a same or different and a plurality of Xs are each a same or different.

6. The pattern-forming method according to claim 1 , wherein the organic solvent has a standard boiling point of no greater than 220° C.

7. The pattern-forming method according to claim 1 , wherein the content of the organic solvent is no less than 2% by mass and no greater than 30% by mass.

8. The pattern-forming method according to claim 1 , wherein a relative permittivity of the organic solvent is 20 or greater and 100 or less.

9. The pattern-forming method according to claim 1 , wherein the content of the alkylene glycol monoalkyl ether acetate is no less than 80% by mass and no greater than 99%.

10. The pattern-forming method according to claim 1 , wherein the organic solvent composition further comprises an alcohol having a standard boiling point of less than 150.0° C.

11. The pattern-forming method according to claim 10 , wherein a content of the alcohol is no greater than 10% by mass.

12. The pattern-forming method according to claim 10 , wherein the acid diffusion control agent includes an amide group-containing compound.