p-GaAs/n-Ga₂O₃ heterojunction diode with breakdown voltage of 800 V

As an attractive next generation ultrawide bandgap material,Ga2O3 has been demonstrated to be capable of high voltage operation. However, the lack of shallow p-type dopant in Ga(2)O(3 )leads to difficulties in developing Ga2O3 based bipolar devices. The semiconductor grafting technology, by bonding a single crystalline p-type semiconductor nanomembrane (NM) to n-Ga2O3 to from abrupt heterojunction, offers a way to expand the application ofGa(2)O(3) in bipolar areas. In this Letter, we report a p-GaAs/(001)-Ga2O3 heterojunction diode fabricated using semiconductor grafting technology. The single crystalline GaAs NM was prepared and transferred onto a Ga2O3 substrate, showing good integrity. Diodes of a mesa diameter of 25 mu m were fabricated, showing a high breakdown voltage of similar to 800 V, a power figure of merit of 126.5 MW/cm(2), and a calculated 1D peak electric field of 1.60 MV/cm. The turn on voltage of the diode was determined to be around 1.91 V with an on-off ratio to be 6 x 10(6) at -4/4 V and the specific on resistance to be 5.06 m omega cm(2). The ideality factor was extracted to be approximately 1.34, indicating reasonable interface quality. The interfacial defects and the self-passivation effects of Ga2O3 are discussed, and the theoretical band diagram was analyzed for the p-GaAs/n-Ga2O3 heterojunction. By managing the peak electric field with suitable edge termination techniques, higher breakdown voltage can be expected. In addition, by taking advantage of the InGaAsP alloy system, a wide variety of GaAs-Ga2O3 based high voltage HBT can be further developed.