Optoelectronic Characteristics of UV Photodetector Based on ZnO Nanopillar Thin Films Prepared by Sol-Gel Method

Abstract

ZnO thin films were prepared on a quartz substrate by sol-gel method and a UV photodetector was constructed on the ZnO thin films, with a circular spiral structure in contact with 30 nm IrO₂ electrodes. The ZnO thin films were crystallized at various crystallized temperature (600∼700°C) for 1 hour in pure oxygen atmosphere, and were then analyzed by X-ray diffraction (XRD) and the scanning electron microscopy (SEM) to investigate the thin film crystallized structures. From photoluminescence (PL) and I-V measurement, the 650°C thin film not only possessed a better crystallization but also had nanopillar structures that revealed an excellent characteristic of UV photodetector.