Investigation of Screening Methods for 1.2 kV 4H-SiC MOSFETs Using High Gate Voltage Pulses and Unclampled Inductive Switching

This study investigates the effectiveness of high gate voltage pulse (HVP) stress and unclamped inductive switching (UIS) tests in screening out infant gate oxide failures in 1.2 kV SiC MOSFETs. Foundry-fabricated pristine devices were systematically tested using HVP and UIS screening conditions at room temperature. Short-duration high gate voltage stress proved effective in identifying infant failures. Analysis of screening results from over 4,000 devices revealed a strong correlation between screening rates and drain leakage, suggesting that stringent drain leakage criteria can help rule out potentially weak devices.