METHOD FOR DETERMINING LASER-INDUCED COMPACTION IN FUSED SILICA

摘要

A fused silica glass which exhibits low compaction when exposed to high intensity excimer radiation, also exhibits low optical path distortion after exposure to a high intensity radiation dose. Also disclosed is a method for improving the select ratio of fused silica glass for photolithography, by predicting the optical path distortion of the glass under use by determining the intrinsic densification of the glass at a given number of pulses and fluence per pulse. Mathematical modeling methods are also disclosed for use in producing a fused silica stepper lens having low compaction under high intensity excimer radiation; and for determining optical path distortion caused by high energy radiation in fused silica glass.