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.