Patent ID: 7803512

Claim:
A positive resist composition, comprising: a resin component (A) that exhibits increased alkali solubility under action of acid; and an acid generator component (B) that generates acid on exposure to radiation, wherein said resin component (A) comprises one or more structural units (a1) selected from the group consisting of structural units represented by general formulas (a1-2) and (a1-4) shown below: [wherein, Y represents a lower alkyl group of 1 to 5 carbon atoms or an aliphatic cyclic group; n represents either 0 or an integer from 1 to 3; m represents either 0 or 1; R represents a hydrogen atom, fluorine atom, lower alkyl group of 1 to 5 carbon atoms, or fluorinated lower alkyl group of 1 to 5 carbon atoms; and R 1′ and R 2′ each represent, independently, a hydrogen atom or a lower alkyl group of 1 to 5 carbon atoms], a structural unit (a2) derived from an acrylate ester that contains a lactone-containing monocyclic or polycyclic group, and a structural unit (a3), which is different from said structural unit (a1) and said structural unit (a2), and is derived from an acrylate ester that contains an aliphatic cyclic group-containing, non-acid-dissociable, dissolution-inhibiting group and contains no polar groups; and said acid generator component (B) comprises an onium salt (B1) having an anion portion represented by a general formula (B-01) shown below: R 41 —SO 3 − (B-01) [wherein, R 41 represents an alkyl group or fluoroalkyl group that contains a cyclic group of 4 to 12 carbon atoms].