Boosting the performance of deep-ultraviolet photodetector arrays based on phase-transformed heteroepitaxial β-Ga 2 O 3 films for solar-blind imaging

Solar-blind imaging has attracted considerable interest in both military and civilian applications, spurring the development of high-performance deep-ultraviolet photodetector arrays (PDAs) with wide-bandgap semiconductor materials. Herein, we present a novel method to enhance the performance of solar-blind PDAs (SBPDs) using β-Ga 2 O 3 films obtained by the phase transition of heterogeneous epitaxial sub-stable ε-Ga 2 O 3 , achieved through high-temperature rapid annealing. Metal-semiconductor-metal-type SBPDs based on phase-transformed β-Ga 2 O 3 films exhibited superior performance, including an ultrahigh responsivity of 459.38 A/W, detectivity of 10 14 −10 15 Jones, external quantum efficiency of 10 4 %−10 5 %, rejection ratio ( R 254 / R 365 ) of 10 5 −10 6 , photo-to-dark current ratio of 10 4 −10 6 , fast response speed of 1.01 s/0.06 s, and favorable stability. Notably, the ultrahigh responsivity of β-Ga 2 O 3 -film-based devices was approximately 222-fold higher than that of ε-Ga 2 O 3 film-based devices. The assembled 4 × 5 β-Ga 2 O 3 film-based PDAs exhibited favorable uniformity, repeatability, and high spatial resolution for solar-blind imaging. Our study offers a promising approach for the development of high-performance β-Ga 2 O 3 -based PDAs for solar-blind ultraviolet imaging with potential applications in both military and civilian fields.