Enhanced Breakdown Voltage and Forward Conduction in Dual-Field-Plated β-Ga2O3 Lateral Trench Schottky Barrier Diodes

Dual-field-plated β-Ga2O3 lateral Schottky barrier diodes (SBDs) with trench-etched electrodes were developed to mitigate the soft breakdown caused by poor electric field shielding in planar diodes. The trench design simultaneously optimizes field management and enlarges the Schottky contact area, leading to superior forward conduction performance. Device characterization reveals exceptional performance metrics for the 10 μm anode-cathode spacing (LAC) configuration, achieving a record-low specific on-resistance (RON,SP) of 2.0 mΩ·cm², an ultrahigh rectification ratio of 10¹¹, and near-ideal switching behavior with a subthreshold swing (SS) of 65 mV/dec. The extracted ideality factor (η = 1.12) and Schottky barrier height (qΦB = 1.35 eV) confirm the high-quality nature of the fabricated sidewall Schottky interface. The integrated dual field-plate structure, electrically connected to the Schottky contact, demonstrates effective electric field management, enabling a breakdown voltage (VBR) of 1.15 kV at LAC = 35 μm. This corresponds to an impressive power figure of merit (PFOM = VBR2/RON,SP) of 135 MW/cm², representing one of the highest reported values for β-Ga2O3 single-crystal-based SBDs. These results establish the trench-architecture SBD as a promising candidate for next-generation high-power electronics applications.