5 KHZ HIGH-REPETITION-RATE AND HIGH-POWER XECL EXCIMER-LASER

A 5 kHz high repetition rate excimer laser has been developed. An aver age laser power of 0.56 kW at 5 kHz operation, which remains stable fo r 1 s, is obtained. This duty time is Limited only by overheating of t he switching thyratrons. The 5 kHz operation is attained by some impro vements to the gas conditions, the UV-preionization scheme, and the ga s flow speed in the discharge region. The gas is circulated at an effe ctive flow velocity of 137 m/s by a newly developed two-stage axial bl ower. The gas conditions are optimized experimentally to achieve 5 kHz operation. To obtain uniform preionization, the locations of pin elec trodes for the preionization are determined on the basis of numerical results. (C) 1995 American Institute of Physics.