| abstract |
A chemical amplification type resist composition uses as the base resin a polymer having a molecular weight dispersity of 1.0 to 1.5 which is a polymer comprising recurring units of formula (1) and recurring units of formula (2) or a polymer comprising recurring units of formula (2) wherein R<1 >is alkyl, alkoxyalkyl, acetyl or carbonylalkoxy, 0<p/(p+q)<=1, R<2 >is hydrogen or methyl, and R<3 >is a tertiary hydrocarbon group of 4 to 30 carbon atoms. By virtue of the narrow dispersity effect of the polymer, the resist composition is improved in resolution as compared with prior art base resins having a wide dispersity. Advantages including a high resolution, good pattern profile and storage stability are obtained. |