Effects of On-State Resistance Differences on the Steady-State Temperature Uniformity of Multi-Chip Paralleled SiC MOSFETs Power Modules

For multi-chip paralleled SiC power modules, maintaining temperature uniformity among the chips is essential for improving modules lifetime and operational reliability. This paper focuses on the impact of on-state resistance in SiC MOSFETs on temperature uniformity within the modules. An electro-thermal co-simulation platform considering thermal coupling effects was developed to efficiently evaluate the influence of device parameters on thermal performance. Based on this platform, the impacts of initial on-state resistance variation and the extent of its temperature dependence on temperature uniformity were systematically analyzed. The results show that assigning devices with slightly higher on-state resistance to positions with stronger thermal coupling helps improve overall temperature uniformity. For the studied module layout, maintaining resistance variation within ±8% ensures acceptable temperature uniformity. Furthermore, selecting devices with a gentler temperature-dependent resistance curve also contributes to more uniform temperature distribution. This study provides theoretical guidance and technical support for the thermal design optimization and device selection of high-reliability SiC power modules.