Protective film-forming composition for immersion exposure and pattern-forming method using the same

1. A protective film-forming composition for immersion exposure which is to be formed on a resist, the composition comprising:

(A) a water-insoluble and alkali-soluble resin comprising a repeating unit derived from a monomer having an acid dissociation constant pKa of 8 or more; and

(B) an organic solvent different from an organic solvent used for forming the resist.

2. The protective film-forming composition for immersion exposure as claimed in claim 1 ,

wherein the repeating unit derived from a monomer has a fluoro-alcohol group.

3. The protective film-forming composition for immersion exposure as claimed in claim 1 ,

wherein the repeating unit derived from a monomer has 2 or more acid groups.

4. The protective film-forming composition for immersion exposure as claimed in claim 1 , further comprising a surfactant.

5. A pattern-forming method comprising:

forming a resist film on a substrate;

forming a protective film from the protective film-forming composition as claimed in claim 1 on the resist film;

immersion exposing the resist film; and

developing the exposed resist film.

6. The protective film-forming composition for immersion exposure as claimed in claim 1 , wherein the organic solvent different from the organic solvent used for forming the resist is a non-aqueous solvent.