A 1200-V, 60-A SiC MOSFET Multichip Phase-Leg Module for High-Temperature, High-Frequency Applications

TLDR

The paper designs, fabricates, and tests a high‑temperature, high‑frequency, wire‑bonded multichip phase‑leg module. The module employs paralleled SiC MOSFETs rated 1200 V/60 A, is intended for a 25‑kW three‑phase inverter at 70 kHz, operates up to 200 °C, and incorporates temperature‑dependent MOSFET characterization, high‑temperature packaging selection, and an optimized electrical layout to minimize parasitic ringing. Testing shows that the SiC MOSFETs outperform Si devices in static and switching performance, reveals gate‑oxide stability trade‑offs, and confirms continuous operation at 200 °C.

Abstract

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 a 25-kW three-phase inverter operating at a switching frequency of 70 kHz, and in a harsh environment up to 200 °C, for aircraft applications. 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 compared to Si devices, but meanwhile did reveal 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 °C continuous operation of the SiC MOSFETs was verified.