Vertical β-Ga₂O₃ Schottky Barrier Diodes with Enhanced Breakdown Voltage and High Switching Performance

Herein, vertical Schottky barrier diodes (SBDs) based on a bulk β-Ga₂O₃ substrate are developed. The devices feature an ion-implanted planar edge termination (ET) structure, which can effectively smoothen the electric field peak and reduce the electric field crowding at the Schottky junction edge. Greatly enhanced reverse blocking characteristics including ≈10³× lower reverse leakage current and 1.5× higher breakdown voltage (V_B) are achieved, whereas good forward conduction such as a reasonably high on-state current density and near-unity ideality factor is maintained. In addition, the switching performance of the fabricated vertical β-Ga₂O₃ SBDs is investigated using a double-pulse test circuit. When switching from an on-state current of 350 mA to a reverse-blocking voltage of −100 V, the vertical β-Ga₂O₃ SBDs exhibit fast reverse recovery with a reverse recovery time (t_rr) of ≈14.1 ns and reverse recovery charge (Q_rr) of ≈0.34 nC, outperforming the Si fast recovery diode (FRD) of similar ratings. The results indicate a great promise of vertical β-Ga₂O₃ SBDs for high-voltage fast switching applications.