Method of forming a positive resist pattern in photoresist of o-naphthoquinone diazide and bisazide with UV imaging exposure and far UV overall exposure

摘要

A dually photosensitive composition useful as a photoresist in the manufacture of ICs and the like electronic devices, which is positively photosensitive by exposure to ultraviolet in a relatively small dose but negatively photosensitive by exposure to ultraviolet in a substantially larger dose than above or by exposure to far ultraviolet light, is obtained by admixing a positive-type photoresist material comprising a novolac resin and an o-naphthoquinone diazide compound with a bisazide compound such as 4,4'-diazidodiphenyl sulfide. The inventive photosensitive composition provides a possibility of developing an ingenious technique for patterning of a photoresist layer on the substrate such as a checkboard-like patterned layer by use of a photomask of a line-and-space pattern.