Abstract

One significant drawback of excimer laser ablation of polyimide is the soot and debris that accumulate around the ablation site during the irradiation. In the past few years, it has become known that ablation of polyimide in the presence of helium gas leaves a surface that is significantly free of debris relative to ablation in air.¹ To understand this phenomenon, we have studied the 248-nm excimer laser ablation of polyimide in several different gas environments and different pressures. Our results indicate that blast wave theory can account semiquatiatively for the role played by gas atomic or molecular weight and gas pressure in debris formation.

© 1992 Optical Society of America