通过研究不同外电路参数条件下半绝缘GaAs光导开关的输出电流波形的差异,分析了外电路电参数对GaAs光导开关导通过程和工作模式的影响。实验开关由600 μm厚的半绝缘GaAs晶片制成,电极间隙为12 mm。使用波长为1 064 nm,5.2 mJ的激光脉冲进行了开关的触发实验。使用皮尔森电流探头测量开关放电电流波形。实验发现储能电容、回路电感等外电路参数对开关放电电流波形存在决定性影响,回路电感影响了导通电流的上升前沿,储能电容对于开关非线性模式的维持起决定作用,储能电容较大时才能够提供非线性模式维持所需的偏置电场。

The difference of photocurrent waveforms from the semi-insulating GaAs photoconductive semiconductor switch(PCSS) when using different exterior electric parameters has been investigated. According to the results the influence of exterior electric parameters has been discussed. The test switch was fabricated of 600 μm thick semi-insulating GaAs and the gap was 12 mm. The PCSS was illuminated by laser pulse with incident optical energy of 5.2 mJ at wavelength of 1 064 nm and the photocurrent waveforms were recorded by current probe. The test results show the influence of trigger light,curcuit inductance and storage capacitor on the photocurrent waveform. The rise time is affected by the inductance of the circuit. The capacitor plays a decisive role in the maintaining of the nonlinear mode in PCSS.