| abstract |
The invention provides a photosensitive resin composition useful as a photoresist of chemical amplification type for deep UV lithography such as ArF excimer laser lithography. The resin composition contains, as an acid generator, an alkylsulfonium salt of the general formula (I), wherein R1 is a C7 to C12 alkyl having a bridged alicyclic structure or a C5 to C7 monocyclic alkyl, R2 is an alkyl, R3 is a C5 to C7 beta -oxomonocyclic alkyl or a C7 to C10 bridged cyclic alkyl having oxo group at the beta -position. The general formula (I) is inclusive of novel alkylsulfonium salts in which R1 is norbornyl group, adamantyl group or cyclohexyl group, R2 is methyl group and R3 is beta -oxocyclohexyl group or beta -oxonorbornane-2-yl group. <IMAGE> (I) |