Evaluation of Turning on/off Delay Time Interval as a Precursor for IGBTs Gate Oxide Degradation

The reliable operation of the power converters is of significant importance since they are served in many crucial applications. Thus, careful attention should be paid to provide a high level of reliability for the converter components in the design phase and during the converter operation. Regarding the prior research art, insulated gate bipolar transistors (IGBTs) are one of the most fragile elements of power converters. Accordingly, the failure mechanisms and degradation processes of IGBTs should be clarified. There are two types of degradation for IGBTs namely package-related degradation and chip-related degradation. Gate oxide degradation can be distinguished as a very prevailing process in chip-related degradation. To monitor the gate oxide degradation, many precursors have been introduced in previous works. This paper investigates the variation of turning on/off delays of the device during the degradation process. The results reveal the acceptable change in turning on/off delays during the degradation process. Hence, the change in turning on/off delay intervals of the IGBTs can be considered as a good precursor for the IGBTs gate oxide degradation.