β-Ga₂O₃ Schottky Barrier Diodes Utilizing Ammonia Plasma Surface Treatment Yield Enhanced Characteristics

In this work, we demonstrate high-performance vertical $\beta $ -Ga2O3 Schottky barrier diodes (SBDs) using ammonia plasma surface treatment (APT) and self-aligned mesa termination (MT). The APT reduces the interface trap density to $3.6\times 10^{{11}}$ cm ${}^{-{2}}$ eV ${}^{-{1}}$ , while the MT suppresses the peak electric field at the anode edge. This combination results in a breakdown voltage of 2034 V with a specific on-resistance of 3.31 m $\Omega \cdot $ cm2, achieving a high power figure of merit of 1.25 GW/cm2. The reduction of Ga-suboxide and adsorbed oxygen improves the interface quality of Ni/ $\beta $ -Ga2O3 SBDs by APT, leading to excellent forward characteristics with an ideality factor reaching 1.012. This work highlights the potential of combining APT and MT to enhance $\beta $ -Ga2O3 SBDs for power applications.