Packaging of a Double-Side Cooled 3.3 kV, 100 A SiC MOSFET Phase-Leg Module

This paper presents the design, fabrication, and testing of a double-side cooled 3.3 kV and 100 A half-bridge power module for applications in heavy duty industrial e-mobility, ultra-fast DC chargers, and grid-tied systems. For robust performance and effective thermal management, we employed a silicon nitride (Si3N4) active metal brazed (AMB) substrate and a porous silver post for module packaging. Steady-state thermal simulations indicated a junction temperature of 99.4 degrees Celsius under a 156 watts per square centimeter heat flux with a heat transfer coefficient of 5000 watts per square meter per degree Celsius, a typical liquid-cooling condition. Thermo-mechanical simulations revealed the maximum von Mises stress of 29.3 megapascals at 150 degrees Celsius at the post-to-die attach interface. Static electrical characterization of the module revealed an average on-resistance of 26.5 milliohm, a 1.5 milliohm higher than the unpackaged devices. The packaging process is a demonstration of a simple manufacturing technology for making low-profile, high-junction-temperature, and robust medium-voltage power modules.