Positive working photoresist composition

摘要

Provided is a positive working photoresist composition comprising (A) an alkali-soluble novolak resin obtained by condensation reaction of a mixture of phenols, which are constituted of specified proportions of m-cresol and two kinds of specific phenols, with an aldehyde and having a Mw/Mn ratio of from 1.5 to 4.0 (wherein Mw stands for a weight-average molecular weight, and Mn stands for a number-average molecular weight); (B) a 1,2-naphthoquinonediazide-5-(and/or -4-)sulfonic acid ester as a photosensitive material; and (C) a low molecular weight compound having from 12 to 50 carbon atoms per molecule and from 2 to 8 phenolic hydroxy groups per molecule.