A 1200-V, 60-A SiC MOSFET Multichip Phase-Leg Module for High-Temperature, High-Frequency Applications
In this paper, a high-temperature, high-frequency, wire-bond-based multichip phase-leg module was designed, fabricated, and fully tested. Using paralleled Silicon Carbide (SiC) MOSFETs, the module was rated at 1200 V and 60 A, and was designed for aircraft applications using a 25-kW three-phase inverter operating at a switching frequency of 70 kHz in a harsh environment of up to 200 oC,. To this end, the temperature-dependent characteristics of the SiC MOSFET were first evaluated. The results demonstrated the superiority of the SiC MOSFET in both static and switching performances as compared to the Si devices, all the while revealing the design tradeoff in terms of the device's gate oxide stability. Various high-temperature packaging materials were then extensively surveyed and carefully selected for the module to sustain the harsh environment. The electrical layout of the module was also optimized using a modeling and simulation approach, in order to minimize the device parasitic ringing during high-speed switching. Finally, the static and switching performances of the fabricated module were tested, and the 200 oC continuous operation of the SiC MOSFETs was verified.