Enhanced performance of solar-blind ultraviolet photodetector based on Mg-doped amorphous gallium oxide film

In this work, Mg-doped amorphous gallium oxide (Mg:GaOx) film is first reported for the fabrication of high-performance solar-blind ultraviolet (SBUV) photodetectors (PD). Compared with un-doped amorphous gallium oxide SBUV PD, the Mg:GaOx-film-based SBUV PD exhibits a lower dark current of 48 pA, a larger on/off ratio (I255 nm light/Idark) of 338, and a faster response speed (a rise time of 0.02 s and a decay time of 0.15 s). Its low dark current and fast response speed can be attributed to the reduction of oxygen vacancies induced by the Mg divalent ions doping in the amorphous gallium oxide film.