2-kV/16-A β-Ga₂O₃ Schottky Barrier Diodes With Surface Killer Defects Reduced by Ar Plasma Treatment

Schottky Barrier Diodes (SBDs) made of ultra-wide-bandgap β-Ga2O3boast high Baliga Figure-of-Merit, but the premature breakdown induced by surface killer defects hinders the scale-up of device area, and therefore, the current rating. In this work, we demonstrate that Ar plasma treatment effectively reduces the density of surface killer defects, leading to more uniform performance in small-area SBDs. The improved uniformity at small scale provides a reliable foundation for scaling to large-area devices. Based on this approach combined with oxygen annealing, we fabricated β-Ga2O3SBDs with a 3 × 3 mm2active area and a composite p-NiO/BaTiO3 edge termination. The devices exhibit breakdown voltages exceeding 2 kV and sustain a high ON-current of 16 A at 2 V forward bias at room temperature, while maintaining a breakdown voltage above 1.8 kV and an ON-current of 13.7 A at 2 V even at 450 K. These results highlight the dual benefits of plasma defect suppression in achieving both device uniformity and robust large-area capability, underscoring the promise of β-Ga2O3SBDs for high-power applications.