Characterization of Ag/ZnO Nanorod Schottky Diode-Based Low-Voltage Ultraviolet Photodetector

Abstract

Ultraviolet (UV) detection characteristics of Ag Schottky contacts with ZnO nanorods (ZnO-NRs) grown on Indium Tin Oxide (ITO)-coated glass substrates have been investigated. A low-temperature hydrothermal method was used for growing ZnO-NRs. Circular contacts of Ag were deposited above the ZnO-NRs/ITO samples using the shadow mask technique. The structural properties of the ZnO-NRs were characterized by using scanning electron microscopy (SEM), atomic force microscope (AFM) and X-ray diffraction (XRD). The results revealed a (0002) crystal orientation and a wurtzite hexagonal structure. The electrical characteristics of the Ag/ZnO-NR Schottky contacts were studied at forward applied bias over the range 0[Formula: see text]V to 1[Formula: see text]V, under dark and UV illumination. The dark and photocurrents were [Formula: see text][Formula: see text]A and [Formula: see text][Formula: see text]A, respectively, and the contrast ratio (ratio of photocurrent to dark current) was 1.67 at [Formula: see text]1.0[Formula: see text]V for these devices. The results show that these devices could be useful for cost-effective and low-voltage UV detection applications.