Anode Failure Mechanism of GaAs Photoconductive Semiconductor Switch Triggered by Laser Diode

Abstract

This paper presents an experimental study on the failure mechanism of high-current gallium arsenide photoconductive semiconductor switches (GaAs PCSSs) triggered by the laser diode. We propose a Blumlein pulse forming line to test the GaAs PCSS. The result shows that the damage of GaAs PCSS almost occurs at the anode under the circumstances that either anode or cathode is illuminated, since the highest amplitude of Gunn oscillation always occurs on the anode. We speculate that the failure of high-current GaAs PCSS is attributed to the Gunn effect according to the statistics about failure factors of GaAs PCSS. We use a scanning electron microscope to semiquantitatively analyze the compositions of the erosions microball or granules, which are gallium and arsenium. The result proves our speculation.