1.06-kV Polarization Gate-Assisted Si-Based AlGaN/GaN Schottky Barrier Diode With 0.817-GW/cm 2 BFOM and 10 –5 -A/cm 2 Leakage Current

In this work, we report a Si-based AlGaN/GaN Schottky barrier diode (SBD) with polarization gate, which effectively enhances the off-state characteristics by significantly decreasing the background electron concentration. We also propose a common-connected groove-anode structure in the polarization-gated device, which enhances the on-state characteristics by remarkably increasing the electron concentration in the AlGaN/GaN channel. Experimental results show that the fabricated device shows a low turn-on voltage ( ${V}_{\small{ON}}$ ) of ~0.6 V and a specific on-resistance ( ${R}_{{\small{ON}}, \textit {sp}}$ ) of ~1.38 m $\Omega \cdot \text {cm}^{{2}}$ . The reverse leakage current is suppressed to ~ $10^{-{5}}$ A/cm² with the increased breakdown voltage (BV) from 362 to 1062 V, which renders a high Baliga’s power figure-of-merit (FOM) of ~0.817 GW/cm² among the reported Si-based GaN SBDs. The proposed design also features reduced dynamic resistance by ~12% at the stress bias of −150 V. The measured temperature-dependent reverse current–voltage ( $I$ – $V$ ) characteristics also show that the polarization gate helps suppress the defect-related electron tunneling effect at the Schottky contact region. This favors the improved thermal stability for the proposed device.