Arrays of Solar-Blind Ultraviolet Photodetector Based on $\beta$ -Ga2O3 Epitaxial Thin Films

Recently, the β-Ga₂O₃-based solar-blind ultraviolet photodetector has attracted intensive attention due to its wide application prospects. Photodetector arrays can act as an imaging detector and also improve the detecting sensitivity by series or parallel of detector cells. In this letter, the highly integrated metal-semiconductor-metal structured photodetector arrays of 32 x 32, 16 x 16, 8 x 8, and 4 x 4 have been designed and fabricated for the first time. Herein, we present a 4-1 photodetector cell chosen from a 4 x 4 photodetector array as an example to demonstrate the performance. The photo responsivity is 8.926 x 10^-1 A/W @ 250 nm at a 10-V bias voltage, corresponding to a quantum efficiency of 444%. All of the photodetector cells exhibit the solar-blind ultraviolet photoelectric characteristic and the consistent photo responsivity with a standard deviation of 12.1%. The outcome of the study offers an efficient route toward the development of high-performance and low-cost DUV photodetector arrays.