Research on Flashover Characteristics and the Physical Mechanism of High-Gain GaAs Photoconductive Switches

We have presented surface flashover characteristics of high-gain GaAs photoconductive semiconductor switch (PCSS) under the different output current. Under the low output current, the recorded flashover spectrum was different from the spark discharge spectrum of air. Based on the analysis of current waveform and the flashover spectrum, the physical mechanism of the flashover phenomena was discussed. Under the high output current, the recorded time waveform of flashover was periodic oscillation. This phenomenon was analyzed based on pinch effect. Finally, the mechanism of the surface flashover led to the damage of GaAs PCSS, which was demonstrated and analyzed.