Positive-working resist composition

摘要

Proposed is a novel chemical-sensitization positive-working photoresist composition used in the photolithographic patterning process for the manufacture of fine electronic devices, which is capable of giving, with high photosensitivity to ArF excimer laser beams, a patterned resist layer having an excellently orthogonal cross sectional profile and high resistance against dry etching and exhibiting good adhesion to the substrate surface. While the composition comprises (A) a film-forming resinous ingredient which undergoes an increase of alkali solubility by interacting with an acid and (B) a radiation-sensitive acid-generating agent, the most characteristic feature of the invention consists in the use of a specific acrylic resin as the component (A), which comprises the monomeric units of a (meth)acrylic acid ester of hydroxy bicyclo[3.1.1]heptanone unsubstituted or substituted by an alkyl group such as hydroxypinanone (meth)acrylate, optionally, in combination with the monomeric units derived from (meth)acrylic acid and/or tert-butyl (meth)acrylate in a molar fraction of 3:7 to 7:3.