Polymer, Resist Composition and Patterning Process

摘要

A polymer comprising recurring units containing silicon and recurring units having a substituent group of formula (1) is novel wherein A¹ is a divalent group selected from furandiyl, tetrahydrofurandiyl and oxanorbornanediyl, R¹ and R² are selected from monovalent C₁-C₁₀ hydrocarbon groups, or R¹ and R² taken together may form an aliphatic hydrocarbon ring with the carbon atom, and R³ is hydrogen or a monovalent C₁-C₁₀ hydrocarbon group which may contain a hetero atom. The polymer is useful as a base resin to formulate a resist composition which is sensitive to high-energy radiation, and has excellent sensitivity and resolution at a wavelength of less than 300 nm as well as satisfactory oxygen plasma etching resistance.