EFFECTS OF AIR LEAKS ON XECL LASER PERFORMANCE

The effects of traces of oxygen and nitrogen on the initial laser powe r and on the gas lifetime of a xenon chloride excimer laser have been studied. When present in atmospheric proportions, nitrogen is found to have the dominant deleterious effect. The reaction, under laser condi tions, with HCl and H-2 forming the benign precipitate NH4+Cl- is obse rved. With HCl injections, a N-2 contaminated gas mixture is found to be ''self-purifying'' over periods of similar to 2 X 10(6) shots. The effects of O-2 contamination can also be largely counteracted by HCl i njections. Conversely, injection of HCl into an old, but not intention ally contaminated, gas mixture causes a decline in the laser power.