The Role of Line-Shaped Defects in Premature Breakdown of $\beta-\text{Ga}_{2}\mathrm{O}_{3}$ Power Diode and Suppression by Oxygen Annealing

In this work, we illuminate the impact of line-shaped defects (LDs) on the premature breakdown phenomena observed in
$\beta-\text{Ga}_{2}\mathrm{O}_{3}$
Schottky barrier diodes (SBDs). Adopting the Conductive Atomic Force Microscopy (C-AFM) and Kelvin Probe Force Microscopy (KPFM) technique, it has been determined that LDs manifest local electrical properties characterized by larger reverse current and lower surface potential. Additionally, the high-temperature oxygen annealing has been proved to be an effective method in decreasing this killer defect density, in favor of the fabrication of SBDs with a breakdown voltage in excess of 2100 V. This study establishes a relationship between the blocking ability of
$\beta-\text{Ga}_{2}\mathrm{O}_{3}$
SBDs and killer defects, offering valuable insights into the mechanism underlying the reverse characteristics of SBDs, as well as guidance for high-quality crystal growth and device design.