Proposal of a GaN/SiC Hybrid Field-Effect Transistor for Power Switching Applications

Abstract

A GaN/SiC hybrid field-effect transistor (HyFET) is proposed as a high-voltage power device that provides a high-mobility lateral AlGaN/GaN channel to reduce the channel resistance and a vertical SiC drift region to sustain the high OFF-state voltage. The performance of the HyFET is evaluated by numerical device simulations. Compared with the conventional SiC MOSFET, the HyFET exhibits a greatly reduced $R_{\mathrm{\scriptscriptstyle ON}}$ together with a low $C_{\mathrm{ GD}}$ and low gate charges. The figures of merit $Q_{\mathrm{ G}}\times R_{\mathrm{\scriptscriptstyle ON}}$ and $Q_{\mathrm{ GD}}\times R_{\mathrm{\scriptscriptstyle ON}}$ of the HyFET are dramatically improved.