Investigation of an Opposed-Contact GaAs Photoconductive Semiconductor Switch at 1-kHz Excitation

The transient performance of gallium arsenide (GaAs) photoconductive semiconductor switches (PCSSs) triggered by laser diodes (LDs) at nano-joules (nJ) energy is of great significance for the potential high-power applications at high repetition rates. An opposed-contact GaAs PCSS with Ni/AuGe/WTi/Au electrodes is presented at single-shot and 1-kHz excitation. The influences of bias electric field up to 80 kV/cm on nonlinear characteristics are investigated quantitatively with a carriers' avalanche multiplication factor as high as 0.8×10 ⁴ . The effect of electric field on the carriers' dynamic process and thermal accumulation in repetitive operation is analyzed. The transient electric field distribution is demonstrated by an ensemble Monte Carlo simulation.