Resist compositions comprising a phenolic resin, an acid forming onium salt and a tert-butyl ester or tert-butyl carbonate which is acid- cleavable

摘要

A positive photoresist composition is provided which can be used in the presence or absence of atmospheric moisture. There is used a major amount of a commercially available resin, such as a novolak, a dissolution inhibitor with thermally labile t-butyl ether or ester groups, and an aryl onium salt.