High-Voltage and Low-Leakage AlGaN/GaN Tri-Anode Schottky Diodes With Integrated Tri-Gate Transistors

Abstract

We present AlGaN/GaN nanostructured Schottky barrier diodes (SBDs) on silicon substrate with high breakdown voltage ( $\mathrm {V}_{\mathrm{BR}}$ ) and low reverse leakage current ( $\mathrm {I}_{\mathrm{ R}}$ ), based on a hybrid of tri-anode and tri-gate architectures. The fabricated SBDs presented a small turn-on voltage ( $\mathrm {V}_{\mathrm{on}}$ ) of 0.76 ± 0.05 V, since the tri-anode architecture formed direct Schottky contact to the 2-D electron gas (2DEG). The reverse characteristic was controlled electrostatically by an embedded tri-gate transistor, instead of relying only on the Schottky barrier. This resulted in low $\mathrm {I}_{\mathrm{ R}}$ below 10 and 100 nA/mm at large reverse biases up to 500 and 700 V, respectively. In addition, these devices exhibited record $\mathrm {V}_{\mathrm{BR}}$ up to 1325 V at $\mathrm {I}_{\mathrm{ R}}$ of $1~\mu \text{A}$ /mm, rendering an excellent high-power figure-of-merit (FOM) of 939 MW/cm2 and demonstrating the significant potential of nanostructured GaN SBDs for future efficient power conversion.