Visible-blind, ultraviolet-sensitive photodetector based an SrTiO3 single crystal

High-sensitivity and visible-blind ultraviolet (UV) photoconductive detectors based on SrTiO3 single crystal with interdigitated electrodes are reported. The responsivities of photovoltage and photocurrent can reach 2.13 x 10(5) V/W and 213 mA/W, respectively, at 330 nm at ambient temperature, and the corresponding quantum efficiency eta reaches 80.2%. The dark current is lower than 50 pA at 10 V bias, and the UV/visible contrast ratio is about four orders of magnitude with a sharp cutoff at 390 nm. The experimental results demonstrate that SrTiO3 single crystal has potentially wide applications in UV detection. (c) 2007 Optical Society of America.