Photoacid generators, chemically amplified resist compositions, and patterning process

摘要

Photoacid generators have formula (1) wherein R¹ and R² are alkyl, or R¹ and R², taken together, may form a C₄-C₆ ring structure with sulfur, R is hydrogen or alkyl, R' is hydrogen, alkyl, alkoxyl or nitro, n is 1 to 6, and Y^- is alkylsulfonate, arylsulfonate, bisalkylsulfonylimide or trisalkylsulfonylmethide. Chemically amplified resist compositions comprising the same have improved resolution, thermal stability, storage stability and minimized line edge roughness