Intrinsic Photoconductive Switches Based on Semi-Insulator 4H-SiC

A high-purity semi-insulator 4H-SiC intrinsic photoconductive switch is presented. The photoconductive semiconductor switch device is fabricated as lateral structures with the electric contact on the same side. The effect of the SiO2 passivation layer has been investigated on the breakdown voltage. The minimum ON-state resistance is 16 Omega, and the breakdown voltage is 11 kV. A new phenomenon that two steps exist on the rising edge of the photocurrent is observed, and a model of resistor and capacitor in parallel is built to explain it.