Novel ester compounds, polymers, resist compositions and patterning process

摘要

An ester compound of the following formula (1) is provided. R1 is H, methyl or CH2CO2R3, R2 is H, methyl or CO2R3, R3 is C1-C15 alkyl, Z is a divalent C2-C20 hydrocarbon group which forms a single ring or bridged ring with the carbon atom and which may contain a hetero atom, m is 0 or 1, n is 0, 1, 2 or 3, and 2m+n=2 or 3. A resist composition comprising as the base resin a polymer resulting from the ester compound is sensitive to high-energy radiation, has excellent sensitivity and resolution, and is suited for micropatterning using electron beams or deep-UV.