Understanding the Thermal Characteristics of SiC Power MOSFET Device for Power Modules Design

Due to the excellent characteristics of the SiC MOSFET, it is more and more widely used in power electronics applications. However, the device is confronted with severe thermal issues due to the smaller chip area. Accordingly, many pieces of research are aimed at better removing the heat energy of the device. However, while reducing thermal resistance, the number of layers inside the package tends to decrease, resulting in a decrease in its heat capacity. This is extremely detrimental to the reliability of the power module, therefore it is necessary to comprehensively consider thermal resistance and heat capacity. Besides, when designing and optimizing the power modules, the device is simply regarded as a uniform heat source, which will cause multiple key pieces of information to be ignored. Therefore, this paper analyzes the thermal characteristics of the SiC MOSFET under transient and steady-state conditions from the perspective of the device and packaging. Finally, guidelines for the design of power modules are provided based on the previous analysis.