Accelerated aging test for gate-oxide degradation in SiC MOSFETs for condition monitoring

In this paper, a method for the condition monitoring of the gate-oxide degradation in silicon carbide (SiC) metal-oxide-semiconductor-field-effect transistors (MOSFETs) is presented. To identify the gate-oxide degradation in SiC MOSFETs, a high-temperature gate bias (HTGB) test, which is an accelerated aging test, is usually performed. This paper proposes an advanced HTGB test for power devices. The test is suitable for developing a condition monitoring system for power devices because the test can accelerate the device aging under switching conditions. Electrical parameter changes in the SiC MOSFETs are demonstrated in the test results. Furthermore, a condition monitoring technique using the input capacitance C-iss change of the SiC MOSFETs is proposed.