Full β-Ga₂O₃ films-based p-n homojunction

Fabricating the p-n junction and exploring the device physics play key roles in developing various functional devices and promoting their practical applications. Although ultrawide bandgap semiconductors have great potentials to fabricate high-voltage and high-efficiency power devices, the lack of p-type Ga₂O₃ poses a fundamental obstacle for fabricating the Ga₂O₃ p-n homojunction and impedes the development of full Ga₂O₃-based bipolar devices. In this study, n-type Sn-doped β-Ga₂O₃/p-type N-doped β-Ga₂O₃ films are prepared by a novel phase-transition growth technique combined with sputter deposition. Full β-Ga₂O₃ one-sided abrupt p-n homojunction diodes are fabricated and the device physics are explored in detail. The diodes possess a high rectification ratio of 4 × 10⁴, a low specific on-resistance of 9.18 mΩ cm² at 40 V, a built-in potential of 4.41 V, and an ideal factor of 1.78, and also show a good rectification behavior under alternating voltage with no overshoot and longterm stability. Our results clear away the major obstacle to β-Ga₂O₃ p-n homojunction, lay the foundation for β-Ga₂O₃ homogeneous bipolar devices, and pave the way for the evolution of high-voltage and high-power device applications.