Self-powered solar-blind detector array based on ε-Ga₂O₃ Schottky photodiodes for dual-mode binary UV communication

In this work, a solar-blind UV metal-semiconductor Schottky photodiode array is constructed by using metalorganic chemical vapor deposition grown ε-Ga₂O₃ thin film, possessing high-performance and self-powered characteristics, toward dual-mode (self-powered and biased modes) binary light communication. For the array unit, the responsivity, specific detectivity, and external quantum efficiency are 30.8 A/W/6.3 × 10^-2 A/W, 1.51 × 10⁴%/30.9%, 1.28 × 10¹⁴/5.4 × 10¹² Jones for biased (-10 V)/self-powered operation. The rise and decay time are 0.19 and 7.96 ms at biased modes, respectively, suggesting an ability to trace fast light signal. As an array, the deviation of photocurrent is only 4.3%, highlighting the importance of accurate information communication. Through certain definition of "1/0" binary digital information, the "NY" and "IC" characters are communicated to illustrate the self-powered and biased modes by right of ASCII codes, based on the prepared ε-Ga₂O₃ solar-blind UV Schottky photodiode array. This work made dual-mode binary deep-UV light communication come true and may well guide the development of UV optoelectronics.