GENERATION OF INTENSE EXCIMER RADIATION FROM HIGH-PRESSURE HOLLOW-CATHODE DISCHARGES

By reducing the diameter of the cathode opening in a hollow cathode di scharge geometry to values on the order of 100 mu m, we were able to o perate these discharges in noble gases in a direct current mode up to atmospheric pressure. High-pressure discharges in xenon were found to be strong sources of excimer radiation. Highest intensities at a wavel ength of 172 nm were obtained at a pressure of 400 Torr. At this press ure, the vacuum ultraviolet (VUV) radiant power of a single discharge operating at a forward voltage of 220 V and currents exceeding 2 mA re aches values between 6% and 9% of the input electrical power. The poss ibility to form arrays of these discharges allows the generation of fl at panel VUV lamps with radiant emittances exceeding 50 W/cm(2) (C) 19 98 American Institute of Physics.