2.86-kV Vertical Cu2O/Ga2O3 Heterojunction Diodes with Stepped Double-layer Structure

Abstract

High-performance Cu2O/β-Ga2O3 heterojunction diodes (HJDs) with a notable breakdown voltage of 2860V were achieved by employing a stepped double-layer (SDL) structure of Cu2O. The device exhibits a turn-on voltage of 1.2V, a specific on-resistance of 8.1 mΩ·cm2, and a power figure-of-merit exceeding 1.0GW/cm2. Additionally, the HJD-SDL demonstrates consistent thermal stability, operating normally at temperatures up to 473K. Simulation results indicate that the SDL structure, consisting of a p+ Cu2O/p- Cu2O structure, significantly enhances breakdown performance by effectively suppressing the peak electric field and redistributing it within the device bulk. The temperature-dependent I–V analysis reveals the variations in electrical performance parameters underlying the forward conduction mechanism. The interface trap density at Cu2O/Ga2O3 heterojunction is determined through frequency-dependent capacitance and conductance measurements. These findings provide a promising and effective strategy for the development of Ga2O3 bipolar power electronics.