Hexahydroxybenzophenone sulfonate esters of diazonaphthoquinone sensitizers and positive photoresists employing same

Abstract

Positive photoresists formulations for producing positive photoresist images having improved thermal stability yet which allow a wide variation in resin to photoactive sensitizer compound without significant changes in photospeed, thermal behavior, contrast or resolution and with virtually no less in unexposed areas of the photoresist and without significant outgassing or popping are provided by employing novel 1,2-diazonaphthoquinone-4- or -5- sulfonate esters of 2,3,4,3',4',5'-hexahydroxybenzophenone with a novel isomeric distribution of esters. The novel isomeric distribution of 1,2-diazonaphthoquinone-4- or -5- sulfonate esters of 2,3,4,3',4',5'-hexahydroxybenzophenone is characterized by two major isomers, together comprising at least about 70% by weight of the photoactive compound, and wherein the least polar isomer comprises only about 40%.

Dependencies are inferred from the claim text.