Published online by Cambridge University Press: 08 May 2015
Silicon carbide (SiC) is the next-generation power semiconductor material, enabling an energy-efficient future society by drastically reducing energy loss in existing power electronics systems. SiC metal oxide semiconductor field-effect transistors (MOSFETs) are promising low-loss power-electronics devices. We have developed precisely controlled doping techniques for ultrathin and highly doped SiC epitaxial films and applied this to form the channels of SiC-MOSFETs. This has resulted in the successful formation of diode-integrated MOSFETs (DioMOSs), a structure enabled using SiC semiconductor material. The MOSFET current together with the diode current of the DioMOS is designed to maintain low conduction loss and good temperature stability. The high threshold voltage of MOSFETs and the perfect unipolar conduction with fast switching contribute to safety and low-loss operation. DioMOS offers a single-chip solution for next-generation power electronics compared to the parallel connection using a diode and a transistor in a conventional semiconductor device. DioMOS achieves a small and light direct current converter with high voltage, current, efficiency, and power density applicable to electric and hybrid vehicles.