(Invited) NiO/ β-(Al _x Ga_1-x )₂O₃ /Ga₂O₃ Heterojunction Lateral Rectifiers with Reverse Breakdown Voltage > 7kV

NiO/ β-(Al x Ga 1- x ) 2 O 3 /Ga 2 O 3 heterojunction lateral geometry rectifiers with diameter 50-100 µm exhibited maximum reverse breakdown voltages >7kV, showing the advantage of increasing the bandgap using the β-(Al x Ga 1- x ) 2 O 3 alloy. This Si-doped alloy layer was grown by Metal Organic Chemical Vapor Deposition with an Al composition of ~21 %. On state resistances were in the range 50-2180 Ω.cm 2 , leading to power figures-of-merit up to 0.72 MW.cm -2 . The forward turn-on voltage was in the range 2.3-2.5 V, with maximum on/off ratios >700 when switching from 5V forward to reverse biases up to -100V. Transmission line measurements showed the specific contact resistance was 0.12 Ω.cm 2 . The breakdown voltage is among the highest reported for any lateral geometry Ga 2 O 3 -based rectifier.