10-kV 4H-SiC Drift Step Recovery Diodes (DSRDs) for Compact High-repetition Rate Nanosecond HV Pulse Generator

In this paper, the 10-kV 4H-SiC Drift Step Recovery Diodes (DSRDs) are designed, fabricated and characterized for high voltage (HV) pulse generator. Owing to the superior SiC material properties, 65 Field-Limiting-Rings (FLRs), deep mesa etching and multi-leg multi-stage sharpening circuits, high performance compact nanosecond HV pulse generator is realized based on the SiC DSRDs. The results show that the SiC DSRDs have blocking voltage over 10.9 kV, turn-on voltage of 3.41 V, and on-current of 12.6 A at bias of 4.4 V. The HV generator can output maximum voltage up to 10.56 kV with rise time of 1.75 ns, and the maximum operation frequency can reach 1 MHz, while the overall printed circuit board area is only 144 cm
²
. The compact nanosecond HV pulse generator can work at high repetition rate up to MHz range, which is beneficial for its application in portable HV sterilization, biological or medical cell modification instrument and so on.