Improvement of the trade-off between Qrr and IDSS in trench field plate power MOSFETs by proton irradiation of the cathode side

Reducing the reverse recovery charge (Q
rr
) in field plate (FP)-MOSFETs improves the power consumption of DC/DC converters. Although lifetime killer is used to reduce Q
rr
, this increases the off-leakage current. In this study, local lifetime killer in FP-MOSFET is first demonstrated by proton irradiation. A damage peak on the cathode side is found to have more advantages than anode damage and uniform damage. Both the Q
rr
-I
DSS
trade-off and the inherent dynamic avalanche in FP are successfully improved by cathode damage. Furthermore, a low surge voltage with soft recovery waveforms is achieved by cathode damage owing to internal FP snubber. Therefore, local lifetime killer on the cathode side has the potential to realize FP-MOSFETs with low power consumption, low noise, good reliability, and high-speed operation.