Tri-Gated Hybrid Anode AlGaN/GaN Power Diode With Intrinsic Low Turn-on Voltage and Ultralow Reverse Leakage Current

Abstract

In this article, a novel tri-gated hybrid anode AlGaN/GaN power diode (TG-HAD) with intrinsic low turn-on voltage ( ${V}_{\mathrm{\scriptscriptstyle {ON}}}$ ) is demonstrated. A novel forward ${V}_{\mathrm{\scriptscriptstyle {ON}}}$ modulation technique based on an ultrathin barrier (UTB) AlGaN/GaN heterostructure is proposed. ${V}_{\mathrm{\scriptscriptstyle {ON}}}$ of the diode is determined by the intrinsic threshold voltage of the two-dimensional electron gas (2DEG) channel of the UTB heterostructure, which can be precisely controlled and which fundamentally features excellent uniformity by tailoring the AlGaN barrier thickness. On the other hand, compared with the planar GaN diodes, the proposed TG-HAD achieves significant reverse leakage current reduction originating from the effectively suppressed buffer leakage by the tri-gate design. The detailed device characteristics and the underlying mechanisms are investigated by TCAD simulation. The TG-HAD, together with the proposed turn-on voltage modulation technique, is promising for fabricating high performance large periphery devices for power applications.