The Overvoltage LSA Relaxation Mode Study in Photoconductive Semiconductor Switch

The 11mm big gap semi-insulating(SI) GaAs photoconductive semiconductor switch (PCSS) is triggered by pulse laser, steady non-linear output waveforms are shown at 5kV~8kV bias voltage, the linear trend present when the bias voltage is higher than 9kV, the nonlinear Lock-on effect is gradually disappeared with the voltage increasing, eventually the pulse development into a complete linear waveform. Analysis that: the big gap SI-GaAs PCSS operate in higher than many times threshold voltage when switch satisfy 2×10
⁴
s.cm
^-3
≤n
₀
/f≤2×10
⁵
s·cm
^-3
and n
₀
L≥10
¹³
cm
^-2
conditions, switch work in overvoltage LSA(Limit Space charge Accumulate) relaxation mode.