CHEMICALLY AMPLIFIED RESISTS USING 1,2-NAPHTHOQUINONE DIAZIDE-4-SULFONATES AS PHOTOACID GENERATORS

A novel positive chemically amplified resist containing partially t-bu toxycarbonylmethlated poly(4-hydroxystyrene)s and 1,2-naphthoquinone-4 -sulfonates (NQ4)s was investigated. The resists are effective for a w ide region of UV lights including i-line and KrF excimer laser lights. The NQ4s photodecompose to form sulfonic acids which accelerate the d ecomposition of t-butyl moieties of the polymers to form carboxylic ac id. Only a few % of NQ4s realize the chemically amplified resists. NQ4 s having electron-withdrawing groups give resists with high sensitivit ies which provide excellent subhalf micron patterns when exposed to ei ther i-line light or KrF excimer laser.