Enhancing Continuous Switching Stability of β-Ga₂O₃ SBDs Through Epitaxial Surface Condition and Edge Termination Optimizations

This study addresses the stability issue of β-Ga₂O₃ Schottky barrier diodes (SBDs) under continuous switching stress. By optimizing epitaxial surface conditions and implementing Nitrogen-implanted edge termination (ET), devices exhibit enhanced static and dynamic stability. Static results reveal the reverse voltage of > 1 kV (at 0.01 A/cm²) and a Baliga figure of merit (BFOM) of over 169 MW/cm². A continuous switching stress test was conducted, which is intended to provide guidance on system-level implications, demonstrating negligible turn-on voltage (Von) shift (< 50 mV) and current collapse (< 0.8%) under stress voltage (Vstress) of -300 V (125 °C), attributed to the reduced surface oxygen vacancies (52 % lower) and suppressed electric field crowding by ET. X-ray photoelectron spectra (XPS) depth profile reveals a reduction of interface NiOx. TCAD simulations confirm the relocation of peak electric fields to the bulk, mitigating surface-related Von shift. This paper figures out the key factors for enhancing static and dynamic performance of β-Ga₂O₃ SBDs in high temperature high-voltage power switching applications.