Solution-Processed Ga2O3 Films via Thermal Annealing for Solar Blind Ultraviolet Photovoltaic Photodetectors with High Photoresponsivity and Fast Response

In this work, a strategy that enhances the decomposition of organic compounds and suppresses oxygen defects in solution-processed Ga2O3 films is proposed to fabricate high-performance Ga2O3 solar blind ultraviolet (SBUV) photodetectors. The photodetector based on the Ga2O3 film annealed at 800 °C exhibits a high response of ∼17 ms and a high photoresponsivity of ∼15.4 mA/W at a 0 V bias. Through a comparison of the photoelectric properties among the detectors fabricated on the films annealed at high temperature (800 °C) and low temperature (500 or 600 °C), the device based on the Ga2O3 film annealed at higher temperature presents higher photoresponsivity and faster response. The improvement in device performance can be attributed to the decrease in the concentration of organic matter and the density of oxygen defects in the Ga2O3 photosensitive layer after high-temperature annealing. The method proposed in this work can give reference to the fabrication of high-responsivity and fast-response SBUV detectors based on solution-processed films.