A highly efficient UV photodetector based on a ZnO microwire p–n homojunction

Abstract

A highly efficient ultraviolet photodetector was successfully obtained based on a Sb-doped p-type ZnO microwire p–n homojunction which consisted of a single Sb-doped p-type ZnO microwire and a single undoped ZnO microwire. The ultralong Sb-doped ZnO single crystalline microwires were synthesized via a chemical vapor deposition method. The ZnO microwire homojunction showed well-defined rectification characteristics, which indicated the p-type conductivity of the Sb-doped ZnO microwire. An ultraviolet photodetector with an external quantum efficiency of 64.5% was obtained based on the ZnO microwire p–n homojunction. The photodetector showed high wavelength selectivity with a full width at half maximum of 6 nm for the photoresponse peak located at 386 nm.