6 kV/3.4 mΩ·cm² Vertical β-Ga₂O₃ Schottky Barrier Diode With BV²/Ron,sp Performance Exceeding 1-D Unipolar Limit of GaN and SiC

In this work, we show that the <tex-math notation="LaTeX">β </tex-math> -Ga 2 O 3 Schottky Barrier Diode (SBD) can perform beyond the 1-D unipolar limit of the SiC and GaN by employing a deep trench with filled thick SiO 2 layer structure to enhance the breakdown voltage (BV). By doing so, BV and specific on- resistance ( <tex-math notation="LaTeX">Ron,sp </tex-math> ) of 5–6 kV and 3.4 <tex-math notation="LaTeX">mΩ · cm^2 </tex-math> are simultaneously derived on the SBDs with <tex-math notation="LaTeX">β </tex-math> -Ga 2 O 3 epi-layer thickness of 10 <tex-math notation="LaTeX">μ m </tex-math> and diode radius of 90 <tex-math notation="LaTeX">μ m </tex-math> . Therefore, the Baliga’s power figure of merit (P-FOM = BV <tex-math notation="LaTeX">^2 /Ron,sp </tex-math> ) is yielded to be 7.4-10.6 GW <tex-math notation="LaTeX">$/$ </tex-math> cm 2 . To the best of all authors’ knowledge, those P-FOMs are the highest values among all types of SBDs, which is a significant step towards the Ga 2 O 3 SBD performance improvement. Combined with negligible forward hysteresis and low reverse leakage current, vertical <tex-math notation="LaTeX">β </tex-math> -Ga 2 O 3 SBDs with state-of-the-art BV and P-FOM show its great promise for next generation high voltage and high power applications.