Research on Junction Temperature Measurement of SiC MOSFETs Using Electrical Methods and Infrared Thermal Imaging

Silicon carbide (SiC) power devices, particularly Metal-Oxide Semiconductor Field Effect Transistors (MOSFETs), are crucial components of power integrated circuits, and their reliability has always been a major concern. Monitoring the junction temperature of these devices is an important task for thermal management and ensuring their reliability. The large current voltage drop method is widely used for junction temperature monitoring due to its non-destructive and accurate online temperature measurement capabilities. In this method, a three-dimensional model is first established based on the current-voltage equations of the MOSFET, followed by temperature calibration and fitting. The on-state voltage and current are obtained through a sampling circuit at different temperatures, and this data is fed into the three-dimensional model to obtain real-time device temperatures. Experimental validation shows that the model predictions have good effectiveness and high accuracy.