Positive-working photoresist composition with quinone diazide sulfonic acid ester and novolac made from m-cresol, p-cresol and aliphatic phenol with 2-6 carbon atoms

摘要

A positive-working photoresist composition suitable for fine patterning in the manufacturing of semiconductor devices such as VLSIs with high fidelity is proposed. The composition comprises: (A) 100 parts by weight of a phenolic novolac resin prepared by the condensation reaction of a specific ternary mixture of three kinds of phenolic compounds and formaldehyde; and (B) 20-60 parts by weight of a photosensitizer which is preferably an ester of naphthoquinone diazidesulfonic acid and a hydroxylated benzophenone compound. The phenolic mixture is composed of 10-45% by weight of m-cresol, 35-88% by weight of p-cresol and 2-30% by weight of a substituted phenol represented by the general formula R.C.sub.6 H.sub.4.OH, in which R is a monovalent aliphatic hydrocarbon group having 2-6 carbon atoms selected from alkyl and alkenyl groups.