We report the initial results of a large-scale evaluation of production-grade fused silica and calcium fluoride to be used in 193-nm lithographic applications. The samples have been provided by many different suppliers of materials. A marathon irradiation chamber permits simultaneous exposure of as many as 36 samples at 800 Hz, at fluences from 0.2 to ≥4 (mJ/cm2)/pulse and pulse counts in excess of 109 . The initial absorption and the laser-induced absorption are found to vary over a wide range. The compaction of each fused-silica sample follows a power law, but its parameters can differ widely from sample to sample.
© 1999 Optical Society of America
[Optical Society of America ]
V. Liberman, M. Rothschild, J. H. C. Sedlacek, R. S. Uttaro, A. Grenville, A. K. Bates*, and C. Van Peski*, "Excimer-laser-induced degradation of fused silica and calcium fluoride for 193-nm lithographic applications," Opt. Lett. 24, 58-60 (1999)