Fabrication and characterization of an individual ZnO microwire-based UV photodetector

Abstract

In this paper, a single ZnO microwire-based photodetector for the monitoring of ultraviolet (UV) radiation is described. Single crystal ZnO microwires were synthesized using a chemical vapor deposition (CVD) on the Si or Al2O3 substrate. The UV photodetector was fabricated by using in-situ lift-out method in a focused ion beam system to manipulate individual zinc oxide microwire. The photodetector prototype consists of a single ZnO microwire (20 μm in length) and exhibits a response of ∼10 mA/W for UV light (365 nm) under 1 V bias. The transient response measurements revealed relatively fast response. The effect of oxygen adsorption and of different relative humidity conditions on the electronic transport through individual microwire is explored and discussed.