Laser photolytic and low temperature investigations of naphthoquinone diazides in Novolak films

Abstract

The spectral and the kinetic behaviour of the photoresists AZ 2400 and AZ 1350J and relevant model compounds (naphthoquinone diazide derivatives) under lithographic conditions on lamp and high intensity excimer laser irradiation have been studied, both at room temperature and at low temperature (77–298 K). The time-resolved spectra were recorded in the spectral region from 300 to 500 nm at time delays from 10 ns to a few seconds. On photolysis of AZ 2400, two transients were observed and, on photolysis of AZ 1350J, three transients were observed. The medium-time-living transient is the ketene, as proved by IR spectra. On low temperature photolysis, two intermediates are observed. In both cases the first-formed intermediate was determined to be the ketene.