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 lowerature 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 0V to 1V, under dark and UV illumination. The dark and photocurrents were 1.29×10-5A and 2.16×10-5A, respectively, and the contrast ratio (ratio of photocurrent to dark current) was 1.67 at +1.0V for these devices. The results show that these devices could be useful for cost-effective and low-voltage UV detection applications. © 2017 World Scientific Publishing Company.