Upper layer-forming composition and resist patterning method

Abstract

A liquid immersion lithography upper-layer film-forming composition includes (A) a polymer that includes a structural unit (I) shown by the following formula (1), and (S) a solvent. R1 in the formula (1) represents a hydrogen atom, a methyl group, or a trifluoromethyl group. The polymer (A) preferably further includes a structural unit (II) that includes a sulfo group. The polymer (A) preferably further includes a structural unit (III) shown by the following formula (3). R2 in the formula (3) represents a hydrogen atom, a methyl group, or a trifluoromethyl group. R3 represents a linear or branched monovalent hydrocarbon group having 1 to 12 carbon atoms or a monovalent alicyclic group having 3 to 20 carbon atoms, provided that at least one hydrogen atom of the hydrocarbon group or the alicyclic group is substituted with a fluorine atom.

Dependencies are inferred from the claim text.