INFLUENCE OF CATION CONCENTRATION ON ALKALINE DISSOLUTION AND SENSITOMETRIC CHARACTERISTICS OF POSITIVE PHOTORESIST

It has been found that when both an alkali and a salt are present in a developer, the rate of noninductive dissolution of layers of a positi ve photoresist based on a phenol-formaldehyde resin (either exposed or unexposed) is determined by a kinetic equation that indicates a two-s tage nature of the dissolution process deprotonation of the molecules, with subsequent formation of an anion-cation pair. An increase of the cation content in the developer, while the alkalinity is maintained, increases the speed of action; a reduction of the alkalinity increases the contrast of the photoresist system.