Self-developing UV photoresist using excimer laser exposure

Abstract
Nitrocellulose functions as a self-developing photoresist which can be patterned using pulsed excimer laser radiation. The material exhibits a threshold fluence for ablation of 20 mJ/cm2 at a wavelength of 193 nm; this threshold results in higher contrast than can be obtained with most conventional photoresists. The effect of varying the laser wavelength has been examined. A simple model of ablative development has been used to predict the etch rate. The processing stability of the resist has been increased without changing the optical development rate by the addition of a dopant. The resolution of the resist is better than 0.3 μm.