Polymers, resist compositions and patterning process

摘要

Polymers comprising recurring units of formula (1) are provided wherein R1 is a straight, branched or cyclic divalent C1-20 hydrocarbon group or a bridged cyclic hydrocarbon group, R is hydrogen atom or an acid labile group, 0<=m<=3, 0<=n<=3 and 0<=m+n<=6. Using the polymers, chemical amplification positive resist compositions featuring low absorption of F2 excimer laser light are obtained.