Impact of the Case Temperature on the Reliability of SiC MOSFETs Under Repetitive Short Circuit Tests

In this paper, the reliability of SiC MOSFETs under repetitive short-circuit conditions is investigated. At first, the maximum short-circuit withstanding time is studied at three different case temperatures and the critical energy is identified in each case. Thereafter, the repetitive short-circuit tests are performed with fixed pulse time duration and bias voltage. The increasing gate leakage current measured at the interval of repetitive short-circuit tests is observed and the gate oxide failure is confirmed. Then, the results of repetitive short-circuit tests with respect to different case temperatures are presented, which helps to find a correlation between the number of repetitions to failure and the initial case temperature. The impact of repetitive short-circuit tests on the bond wire resistance is also analyzed.