Thermal and Reliability Optimization of Clips in SiC MOSFET Power Modules

Inhalt:
Clip-bonded power modules are extensively utilized due to their high current-carrying capacity and reliability. In the paper, an optimized thick copper-molybdenum clip was proposed to achieve low thermal resistance and high reliability. The impact of clip thickness and material on thermal performance and reliability is analyzed through simulations and experiments. The transient dual-interface method is employed to measure the thermal resistance of modules with clips of different thicknesses and materials. The thermal resistance of the modules with a 3 mm Cu clip and a 3 mm Cu15Mo85 clip is reduced by 13.4% and 10.4% respectively. Moreover, finite element simulations of temperature cycling are conducted to assess the reliability of the solders with different clips. The solder reliability with the 3 mm Cu15Mo85 clip is higher than that with the 3mm Cu clip and is close to that with the 0.1 mm Cu clip.