abstract |
A polymer comprising recurring units of formula (1) wherein R 1 is H or methyl, R 2 is H or C 1-8 alkyl, R 3 is hydrogen or CO 2 R 4 , and R 4 is C 1-15 alkyl and recurring units having a carboxylic acid protected with an acid-decomposable protecting group containing an adamantane or tetracyclo-[4.4.0.1 2,5 .1 7,10 ]dodecane structure and having a Mw of 1,000-500,000 is novel. A resist composition comprising the polymer as a base resin is sensitive to high-energy radiation, has excellent sensitivity, resolution and etching resistance and lends itself to micropatterning with electron beams or deep-UV. |