SiC MOSFET Aging Detection based on Miller Plateau Voltage Sensing

Harsh operating environment and high temperature swings introduce die and packaging related degradations in SiC MOSFETs causing potential system failures. This paper proposes a new SiC MOSFET state-of-health monitoring approach based on Miller plateau voltage sensing. To age the SiC devices in a short time, power cycling test is applied. During the aging process, the device's static parameters and switching transients are evaluated. From the comprehensive assessment results, the Miller plateau voltage is found to be a promising aging precursor for SiC devices. Targeting at aging detection, a practical monitoring circuit is proposed for Miller plateau voltage measurement. Experimental results reveal that the proposed method is valid for on-board SiC MOSFET aging detection during system start-up within microseconds.