High-efficiency electron-beam-excited KrF excimer laser

The conditions for high-efficiency operation of a KrF electron-beam laser were determined. It was found that the amounts of Xe and O₂ impurities present in the gas mixture must not exceed 0.01%. An empirical expression was derived for determining the optimal composition of the active gas mixture. A laser output energy of 14.1 J was obtained from a 0.45-liter active volume with an efficiency η = 9% (in terms of energy input to the active volume) at a gas pressure of 3 atm and for a pulse duration of ~80 nsec. The gain and absorption of the active medium were determined (0.15 and 0.014 cm^–1, respectively) for a specific excitation power of 1.25 MW·cm^–3·atm^–1.