A Monolithic Bi-Directional GaN/SiC Hybrid Field-Effect Transistor

Power electronics systems such as matrix converters require devices that are capable of blocking high voltage and conducting current in both forward and reverse directions. In this work, we present a monolithic bi-directional GaN/SiC hybrid field-effect transistor (BD-HyFET). The device combines the merits of SiC junction field-effect transistor (JFET) structure and p-GaN gated 2-dimensional-electron-gas (2DEG) channel, enabling the inclusion of a high mobility channel and area-efficient vertical voltage blocking structure. The fabricated devices exhibit bi-directional behavior at both OFF-state and ON-state, with almost symmetrical characteristics in the 1(st) and 3(rd) I-V quadrants. Non-destructive off-state breakdown characteristics with breakdown voltages over 600 V were obtained in both forward and reverse directions. The four-quadrant switching characteristics of the GaN/SiC BD-HyFET were verified. In addition, the characteristics of the BD-HyFET as an AC power chopper were successfully demonstrated.