Positive-working photoresist containing o-naphthoquinone diazide sulfonic acid ester and novolak resin consisting of 35 to 43% m-cresol and 65 to 57% p-cresol with substantial absence of o-cresol

摘要

A positive-working photoresist composition suitable for fine patterning in the manufacture of semiconductor devices, e.g., VLSIs, with high fidelity is proposed. The composition comprises 100 parts by weight of a cresol novolac resin and 25-60 parts by weight of a naphthoquinone diazide sulfonic acid ester as the photosensitive component while the cresol novolac resin component is prepared from a mixture of cresol isomers composed of 35-43% of m-cresol and 65-57% of p-cresol with substantial absence of o-cresol or composed of 35-43% of m-cresol, 65-57% of p-cresol and 1% or less of o-cresol.