Development of SiC power devices and modules for automotive motor drive use

Abstract

SiC Power devices are expected to greatly improve the efficiencies and operating capabilities of next generation electric and hybrid electric vehicles. The use of these devices allows for drastic size and weight reduction at the module and system levels of motor drives used in automotive applications. A new SiC MOSFET structure with both gate and source trenches is presented. This greatly reduces device on-resistance while preventing oxide destruction at the gate trench bottoms. Finally new packaging methods under development are outlined that take advantage of the benefits these new devices have to offer by transfer molding them in a high temperature resistant epoxy resin. This leads to modules with low thermal resistance and high power density that, when configured as a three phase inverter, reduce total system footprint and parasitic inductance.