A 1200 V, 60 A SiC MOSFET multi-chip phase-leg module for high-temperature, high-frequency applications

This paper presents the design and test results of a 1200 V, 60 A multi-chip phase-leg module based on SiC MOSFETs. The module will be used in a high-frequency (70 kHz) AC-DC converter, and in high-temperature (200 °C) environment, for aircraft applications. Towards this target, the high-temperature characteristics of the SiC MOSFETs are firstly evaluated. The results show the superiority of SiC MOSFETs in both static and switching performances compared to Si devices. Different high-temperature packaging materials are then surveyed and carefully selected for the module to sustain the harsh environment. An improved substrate layout is also proposed based on the “switch pair” concept in order to reduce the parasitic ringing during switching transients. The concept is validated through the comparison with a regular layout design in both stray inductance analysis and time-domain simulation. Finally, the static and switching performances of the fabricated module are presented.