Abstract: Constructing suitable heterojunction has been proven to be an effective method to improve the performance of photodetectors. To improve the photoelectric performance of Ga₂O₃ solar-blind photodetector, ε-Ga₂O₃/SiC heterojunction photodetectors are fabricated based on epitaxial ε-Ga₂O₃ thin films grown on SiC substrate using metal organic chemical vapor deposition technique. The crystal structure and absorption spectrum show that the single-oriented ε-Ga₂O₃ film exhibits strong absorption in the solar blind region. Benefiting from a strong built-in electric field, the device exhibits outstanding self-driven photoelectric characteristics. The stable photoelectric response can be produced without external applied electric field with a low dark current and high sensitivity. At 0V applied voltage, the photo-to-dark current ratio of the device can reach 10⁴ under 254nm ultraviolet light illumination, with a responsivity of 0.3mA/W and specific detectivity of 1.45×10¹⁰cm·√Hz/W. The development of a self-driven solar-blind photodetector can provide theoretical routes and experimental guidance for the preparation of zero-power-consumption detectors.

Key words: ε-Ga₂O₃, heterojunction, solar-blind photodetector, self-driven