Positive resist composition and method for forming resist pattern using same

摘要

A resist composition is disclosed which is capable of suppressing the surface roughness that occurs within a resist pattern, either following etching or following developing, or preferably following both processes. A resist pattern is formed using a positive resist composition that includes: a resin component (A), which contains at least one structural unit (a1) containing a lactone represented by one of the general formulas (1) through (4) shown below: (wherein, R represents a hydrogen atom or a methyl group, and m is either 0 or 1), and exhibits increased alkali solubility under the action of acid; an acid generator component (B) that generates acid on exposure; and an organic solvent (C).