Theoretical and Experimental Study of UV Detection Characteristics of Pd/ZnO Nanorod Schottky Diodes

Abstract

In this work, we report theoretical and experimental study of Pd/ZnO nanorod (NR) Schottky diodes-based ultraviolet photodetector (UV-PD). The ZnO-NRs are deposited on indium tin oxide (ITO) coated glass substrates by using a lowerature hydrothermal method. The surface morphology of the ZnO-NRs film is characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The SEM image shows vertically grown NRs with uniformity, and XRD shows the preferred (002) orientation of ZnO-NR films. The current-voltage characteristics of Pd/ZnO-NR Schottky diodes are studied under dark and UV light. A voltage bias from-1V to +1V is applied and the ratio of photocurrent to dark current was (a0.17×102 at V=0.5V) calculated from the I-V curve. The value of responsivity was found to be 0.111A/W at I=365nm and at bias=0.50V. An approximated UV-PD structure has also been numerically simulated using three-dimensional (3D) device simulator from Visual TCAD of Cogenda International. The simulated I-V characteristics have also been plotted under both dark and light conditions. The simulated results are found to be following the nature of experimental results. © 2017 World Scientific Publishing Company.