申请人:TACHIBANA Seiichiro
公开号:US20090233223A1
公开(公告)日:2009-09-17
A polymer comprising recurring units of a sulfonium salt represented by formula (1) is provided as well as a chemically amplified resist composition comprising the same. R
1
is H, F, methyl or trifluoromethyl, R
2
to R
4
are C
1
-C
10
alkyl or alkoxy, R
5
is C
1
-C
30
alkyl or C
6
-C
14
aryl, k, m and n are 0 to 3. The recurring units generate a sulfonic acid upon exposure to high-energy radiation so as to facilitate effective scission of acid labile groups in the resist composition. The resist composition exhibits excellent resolution and a pattern finish with minimal LER.