Self-Driven Solar-Blind Photodetector Based on ε-Ga2O3/SiC Heterojunction

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 0 V applied voltage, the photo-to-dark current ratio of the device can reach 104 under 254 nm ultraviolet light illumination, with a responsivity of 0.3 mA/W and specific detectivity of 1.45×1010 cm•(Hz)1/2/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. © 2022, Editorial Department of Journal of Beijing University of Posts and Telecommunications. All right reserved.