Development of an SiC Multichip Phase-Leg Module for High-Temperature and High-Frequency Applications

摘要

This article presents a 1,200-V, 120-A silicon carbidemetal-oxide-semiconductor field-effect transistor (SiC MOSFET)phase-leg module capable of operating at 200°C ambient temperature.Paralleling six 20-A MOSFET bare dice for each switch,this module outperforms the commercial SiC modules in higheroperating temperature and lower package parasitics at a comparablepower rating. The module’s high-temperature capability is validatedthrough the extensive characterizations of the SiC MOSFET,as well as the careful selections of suitable packaging materials.Particularly, the sealed-step-edge technology is implemented on thedirect-bonded-copper substrates to improve the module’s thermalcycling lifetime. Though still based on the regular wire-bond structure,the module is able to achieve over 40% reduction in theswitching loop inductance compared with a commercial SiC moduleby optimizing its internal layout. By further embedding decouplingcapacitors directly on the substrates, the module also allows SiCMOSFETs to be switched twice faster with only one-third turn-offovervoltages compared with the commercial module.