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This paper presents the first integrated temperature sensor in a SiC power mosfet. An analytical model has been proposed to assess its behavior up to 300°C. We present the tested design and its advantages compared to other solutions. We also propose possible optimizations in order to simplify it and reduce its size. 2.25 mm2 power mosfets have been fabricated with and without temperature sensor. Measurements show that the temperature sensor does not impact the power mosfet characteristics and its integration does not demand supplementary process steps. To demonstrate the functionality of our integrated sensor, we have calibrated the temperature dependence of its resistance to assess the internal temperature of the device at different bias. [ABSTRACT FROM AUTHOR]

Under realistic switching conditions, SiC MOSFETs reliability issues remain as a challenge that requires further investigation. In this letter, a specific aging test has been developed to monitor and characterize the electrical parameters of the SiC MOSFET. This allows estimations of the health state and predictions of the remaining lifetime prior to its failure. The gate leakage current seems to be a relevant runaway parameter just before failure. This leakage indicates deterioration of the gate structure. This hypothesis has been validated through analysis of scanning electron microscopy pictures, with a focused ion beam cut showing cracks within the polysilicon. [ABSTRACT FROM AUTHOR]