Patent ID: 7252924

Claim:
A positive resist composition comprising: at least two resins, each comprising: at least one of a repeating unit derived from an acrylic acid derivative monomer and a repeating unit derived from a methacrylic acid derivative monomer; an alicyclic structure; and at least one group that increases solubility of each of the at least two resins in alkaline developer by the action of an acid; and a compound which generates an acid upon irradiation with actinic rays or radiation, wherein a first resin of the at least two resins has a glass transition temperature different from that of a second resin of the at least two resins by at least 5° C., wherein each of the first and second resins comprises at least one repeating unit selected from the group consisting of repeating units represented by formula (A1) and repeating units represented by formula (A2): wherein in formula (A1), R represents a hydrogen atom, a hydroxyl group, a halogen atom, or an alkyl group having 1 or 2 carbon atoms, provided that the R's are the same or different; and in formula (A2), R represents a hydrogen atom, a hydroxyl group, a halogen atom, or an alkyl group having 1 to 4 carbon atoms, provided that the R's are the same or different; A is a single bond or represents one group or a combination of two or more groups selected from the group consisting of alkylene, ether, thioether, carbonyl, ester, amide, sulfonamide, urethane and urea groups; and W 1 represents an alkylene group.