We report on a vertical geometry Mott-type visible (VIS)-blind Ultraviolet (UV)photodetector which was fabricated based on wurzite MgZnO (W-MgZnO) with a cubic MgZnO (C-MgZnO) anti-reflection layer. The C-MgZnO layer plays two roles in the detector, not only the conventional optical part but also electrical part. Photon-generated holes were restricted due to valence band offset. More “hot” electrons injected over a reduced Mott potential barrier at the metal-semiconductor interface, resulting in additional current contributing to photoresponse. This dual-function structure is a highly compact and wavelength-resonant UV detector, with a spectral response high-gain and fast.
Received 17 March 2013Accepted 30 May 2013Published online 12 June 2013
This work is supported by the National Basic Research Program of China (973 Program) under Nos. 2011CB302002 and 2011CB302006, the National Natural Science Foundation of China under Nos. 11134009 and 11104265.