POSITIVE RESIST COMPOSITION AND PATTERN FORMING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a positive resist composition capable of giving high resolution and a good pattern profile, and a pattern forming method using the positive resist composition in liquid immersion lithography including formation of a protective film.SOLUTION: The positive resist composition comprises: (A) a resin that includes a methacrylic acid as a repeating unit which has a specific 2-alkyladamantyl group and a specific 2-alkylcyclopentyl group in a side chain as acid-labile groups, and that shows increase in the alkali solubility by an acid; (B) a sulfonium salt represented by formula (3) and formula (4); and (C) a solvent.SELECTED DRAWING: None