Characteristics of UV-laser triggered pseudospark switch plasma

Summary form only given. The pseudospark switch triggered by an ArF laser was investigated in an effort to understand the fundamental characteristics of the phenomenon. The switch is filled with He of 0.01 to 0.2 torr with flow. Each electrode is made of Cu and separated by 2 mm, with a central hole of 4 to 10 mm in diameter. The discharge is initiated by an unfocused laser beam (30 mJ, 10 ns) incident on the back of the cathode. A peak current of 8 kA was measured at a hold-off voltage of 8 kV with a laser energy of 20 mJ (25 mJ/cm²), and the minimum delay was 80 ns with a jitter of a few nanoseconds. The same switch was also triggered by the surface discharge UV source with smaller electrical input energies. The effects of laser energy, irradiation position, electrode hole diameter, and gas pressure on the switching characteristics were investigated