Patent ID: 7501221

Claim:
A positive type resist composition comprising (A) a resin component comprising within the principal chain a structural unit derived from a (meth)acrylate ester and incorporating an acid dissociable, dissolution inhibiting group containing a polycyclic group on an ester side chain section, for which solubility in alkali increases under action of acid, (B) an acid generator component which generates acid on exposure, and (C) an organic solvent, wherein said component (A) comprises: a structural unit derived from a (meth)acrylate ester, and comprising an acid dissociable, dissolution inhibiting group containing a polycyclic group; a structural unit derived from a (meth)acrylate ester, and comprising a lactone containing monocyclic group or polycyclic group; and a structural unit derived from a (meth)acrylate ester, and comprising a hydroxyl group containing a polycyclic group; wherein one of said structural units is derived from a methacrylate ester and one of said structural units is derived from an acrylate ester, and the relative quantities of the methacrylate structural unit and the acrylate ester structural unit within the component (A) are such that relative to the combined number of moles of the methacrylate ester structural unit and the acrylate ester structural unit, the methacrylate ester structural unit accounts for 10 to 85 mol %, and the acrylate ester structural unit accounts for 15 to 90 mol %, wherein said component (A) comprises a copolymer (A1) with a structural unit derived from a methacrylate ester, and a structural unit derived from an acrylate ester and said copolymer (A1) is a copolymer (d) described below: copolymer (d): a copolymer formed from 30 to 60 mol % of a structural unit (a1′) derived from a methacrylate ester, and comprising an acid dissociable, dissolution inhibiting group containing a polycyclic group, 20 to 60 mol % of a structural unit (a2) derived from an acrylate ester, and comprising a lactone containing monocyclic group or polycyclic group, and 1 to 50 mol % of a structural unit (a3) derived from an acrylate ester, and comprising a hydroxyl group containing polycyclic group.