GaN Schottky ultraviolet photodetectors using the metal-semiconductor-metal structure

Abstract

GaN Schottky ultraviolet photodetectors using the metal-semiconductor-metal structure grown by metalorganic vapour phase epitaxy (MOVPE) are reported. The metal contacts used in this work are Ti/Au or Au. The devices characterised present a low dark current below 1 pA and typical photocurrent I-V characteristics at 360 nm. The photodetectors exhibit internal gain and visible blindness. The responsivity is 0.001 A N in the visible region, which is approximately three orders of magnitude less than the above gap responsivity.