Chemically amplified positive resist composition

摘要

A chemically amplified positive resist composition contains (A) an organic solvent, (B) a base resin in the form of a polyhydroxystyrene having phenolic hydroxyl groups some of which are protected with alkoxyalkyl groups and having a weight-average molecular weight of 3,000-300,000 and a dispersity of 1.0 to 1.5, (C) a photoacid generator, and (D) a vinyl ether group-containing compound. The composition is sensitive to actinic radiation, especially KrF excimer laser beam, has high sensitivity and resolution, and forms a resist pattern having improved plasma etching resistance and heat resistance.