Polymerizable anion-containing sulfonium salt and polymer, resist composition, and patterning process

摘要

A polymerizable anion-containing sulfonium salt having formula (1) is provided wherein R1 is H, F, methyl or trifluoromethyl, R2, R3 and R4 are C1-C10 alkyl, alkenyl or oxoalkyl or C6-C18 aryl, aralkyl or aryloxoalkyl, or two of R2, R3 and R4 may bond together to form a ring with S, A is a C1-C20 organic group, and n is 0 or 1. The sulfonium salt generates a very strong sulfonic acid upon exposure to high-energy radiation. A resist composition comprising a polymer derived from the sulfonium salt is also provided.