Research on on-conduction of 4H-SiC Photoconductive Switch

A coplanar photoconductive switch based on vanadium- nitrogen doped 4H-SiC bulk material was developed. The test results show that the combination of vanadium doping and coplanar electrode structure, the voltage capability of 4H-SiC photoconductive switch is significantly improved and the conductive resistance of 4H-SiC photoconductive switch under low light intensity is reduced. The bias voltage of 4H-SiC photoconductive switch is 10kV. The conductive resistance of 4H-SiC photoconductive switch excited by 0.5mJ 532nm laser is 21 Omega. In the conjugate matching link, the ouput peak power on the load is 0.3MW. The conductive resistance of 4H-SiC photoconductive switch excited by 2.5mJ 532nm laser is less 1 Omega. In the conjugate matching link, the ouput peak power on the load is 6.25MW. The results show that the developed vanadium-nitrogen doped 4H-SiC photoconductive switch has the characteristics of stable output waveform, small jitter and high power. Low conductive resistance can be obtained at low light intensify. The developed vanadium-nitrogen doped 4H-SiC photoconductive switch has certain application value.