An electrically triggered 200 kV rail-gap switch for wide aperture excimer lasers

A wide aperture (7×7 cm2), high output energy (5 J in KrF and 13.8 J in XeC1), UV preionized excimer laser is described. A self-breakdown rail gap was employed as an output switch with the maximum voltage and current up to 230 kV and 300 kA, respectively. To solve the switching jitter problem associated with the self-breakdown, an electrical triggering was investigated. The measured minimum switching time delay and gap closing time were 40 and 10 ns, respectively. The number of channels up to 50 was observed with a uniform distribution over the 80-cm electrode length. The triggering jitter was measured to be less than a nanosecond. The maximum operation voltage of the triggered rail gap was 200 kV. The successful trigger operation was obtained in the range 30%–98% of the self-breakdown voltage.