Ultraviolet Schottky detector based on epitaxial ZnO thin film

In this paper, we have prepared Schottky type ZnO metal–semiconductor–metal (MSM) ultraviolet (UV) detector. The structural, electrical, and optical measurements were carried out. The detector exhibited a peak responsivity of 0.337 A/W at 360 nm and the dark current was about 1 nA under 3 V bias. An ultraviolet–visible rejection ratio was obtained about more than four orders of magnitude from the fabricated detector. The 10–90% rise and fall time were 20 ns and 250 ns, respectively. We proposed that the detector had shown a gain, which was attributed to the trapping of hole carriers at the semiconductor–metal interface.