A Novel High-Temperature Planar Package for SiC Multichip Phase-Leg Power Module

This paper presents the design, development, and testing of a phase-leg power module packaged by a novel planar packaging technique for high-temperature (250 ${^\circ}$ C) operation. The nanosilver paste is chosen as the die-attach material as well as playing the key functions of electrically connecting the devices' pads. The electrical characteristics of the SiC-based power semiconductors, SiC JFETs, and SiC Schottky diodes have been measured and compared before and after packaging. No significant changes (<5%) are found in the characteristics of all the devices. Prototype module is fabricated and operated up to 400 V, 1.4 kW at junction temperature of 250 ${^\circ}$C in the continuous power test. Thermomechanical robustness has also been investigated by passive thermal cycling of the module from −55 ${^\circ}$C to 250 ${^\circ}$C. Electrical and mechanical performances of the packaged module are characterized and considered to be reliable for at least 200 cycles.