Patent ID: 7202016

Claim:
A positive-tone radiation-sensitive resin composition comprising (A1) a copolymer which comprises a recurring unit shown by the following formula (1) and/or a recurring unit shown by the following formula (2), and a recurring unit shown by the following formula (3-1), and (B) a photoacid generator, wherein R 1 represents a hydrogen atom or a methyl group; wherein R 1 represents a hydrogen atom or a methyl group, and R 2 represents a tertiary alkyl group having 4–10 carbon atoms; wherein R 1 represents a hydrogen atom or a methyl group, R 3 and R 4 individually represent a substituted or unsubstituted alkyl group having 1–12 carbon atoms, a substituted or unsubstituted aromatic group having 6–15 carbon atoms, or a substituted or unsubstituted alkoxyl group having 1–12 carbon atoms, or R 3 and R 4 may form, in combination and together with the nitrogen atom with which the R 3 and R 4 groups bond, a cyclic structure having 3–15 carbon atoms, provided that R 3 and R 4 are not a hydrogen atom at the same time.