A Comparative Study of Temperature Sensitive Electrical Characteristics of SiC MOSFETs Considering Structural Variations

SiC MOSFETs are emerging to be utilized in industries due to their benefits of high switching frequency, low loss, and high temperature endurance. As the majority of power device failures are related to the junction temperature, temperature monitoring via the temperature sensitive electrical parameters (TSEPs) is promising to enhance the device reliability. This study compares and analyzes the TSEPs of various 1.2 kV SiC MOSFETs with different chip structures. Experimental comparisons of the devices are executed via the double-pulse tests under device temperatures ranging between 25 ℃ and 175 ℃. According to experimental results, temperature has an impact on the majority of electrical characteristics during SiC MOSFET switching. Temperature has variable effects on devices with different gate structures. Planar gate device is marginally inferior to Trench gate device’s turn-off delay (td,off) in terms of TSEP linearity. The planar one has a substantially higher turn-off delay (td,off) sensitivity in terms of TSEP than the trench one. To accurately measure the junction temperature of the device, it is vital to choose proper TSEP considering the structural variations of devices.