Polymers and chemically amplified positive resist compositions

摘要

The invention provides a novel polymer comprising a recurring unit of formula (1) wherein R1 is hydrogen or methyl, R2 is hydrogen or acid labile group, at least one R2 being hydrogen and at least one R2 being an acid labile group, and n=2 or 3. The polymer's Mw is 3,000-300,000. Blending the polymer as a base resin with an organic solvent and a photoacid generator yields a chemically amplified positive resist composition.