High performance Schottky UV photodetectors based on epitaxial AlGaN thin film

Al0.25Ga0.75N ultraviolet (UV) photodetector was fabricated on Al2O3 by metal organic chemical vapor deposition (MOCVD). Based on the Al0.25Ga0.75N epitaxial layer, planar geometry Schottky type metal-emiconductor-metal (MSM) photodetector was fabricated. The device shown very low dark current about 20 pA at 1 V bias, and the photocurrent/dark current rejection is more than five orders of magnitude. At I V bias, the peak responsivity of 0.07 A/W was achieved at 308 nm, corresponding to the cletectivity about 4.43 x 10(11) cm Hz(1/2)/W. Published by Elsevier B.V.