Microhollow cathode discharge excimer lamps

Microhollow cathode discharges are high-pressure, nonequilibrium gas discha rges between a hollow cathode and a planar or hollow anode with electrode d imensions in the 100 mu m range. The large concentration of high-energy ele ctrons, in combination with the high-gas density favors excimer formation. Excimer emission was observed in xenon and argon, at wavelengths of 128 and 172 nm, respectively, and in argon fluoride and xenon chloride, at 193 and 308 nm. The radiant emittance of the excimer radiation was found to increa se monotonically with pressure. However, due to the decrease in source size with pressure, the efficiency (ratio of excimer radiant power to input ele ctrical power), has for xenon and argon fluoride a maximum at similar to 40 0 Torr. The maximum efficiency is between 6% and 9% for xenon, and similar to 2% for argon fluoride. (C) 2000 American Institute of Physics. [S1070-66 4X(00)95105-X].