Bonn 2000 – scientific programme
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P: Plasmaphysik
P 8: Entladungen II
P 8.6: Talk
Tuesday, April 4, 2000, 18:00–18:15, HS IX
Microhollow Cathode Discharge Excimer Sources — •Robert H. Stark, Ahmed El-Habachi, Mohamed M. Moselhy, Wenhui Shi, and Karl H. Schoenbach — Physical Electronics Research Institute, Old Dominion University, Norfolk, VA 23529, USA
Microhollow cathode discharges are high pressure, nonequilibrium gas discharges between a hollow cathode and a planar or hollow anode with electrode dimensions in the 100 µm range. The large concentration of highenergy electrons, in combination with the high gas density favors excimer formation. Excimer emission was observed in xenon and argon, at wavelengths of 128 nm and 172 nm, respectively, and in argon fluoride and xenon cloride, at 193 nm and 308 nm. The radiant emittance of the excimer efficiency (ratio of radiant power in the UV and VUV to electrical power supplied to the discharge), has a maximum at approximately 400 Torr. For xenon the maximum efficiency is between 6% and 9%, for argon fluoride it is 3%. The large power densities in these micro glow discharges, estimated to be on the order of 106 W/cm3, plus their stability at high gas pressures, even in electronegative gases, opens the possibility to them as laser medium for cw micro excimer lasers. This work was funded by the Department of Energy, Advanced Energy Division and the National Science Foundation (NSF).