Improved UV-Sensing of Au-Decorated ZnO Nanostructure MSM Photodetectors

In this work, we use gold (Au) nanoparticles (NPs) to modify zinc oxide (ZnO) nanostructures and improve the performance of ultraviolet (UV) metal-semiconductor-metal (MSM) photodetectors (PDs). The surface morphology, crystal performance, optical characteristic, and electrical property of the nanostructures were determined by using several instruments [e.g. X-ray diffractometer, field-emission scanning electron microscopy, photoluminescence spectroscopy, X-ray photoelectron spectroscopy, high-resolution transmission electron microscopy, and semiconductor parameter analyser]. Single-crystalline one-dimensional (1-D) nanorods (NRs) with hexagonal wurtzite structures were obtained via a facile hydrothermal synthetic route. The ZnO and Au/ZnO NRs with direct current magnetron sputtering times (i.e. 0 and 10 s) were labelled ZOA-0 and ZOA-1 samples, respectively. When the applied voltage was 1 V, ZOA-0 and ZOA-1 samples had dark currents (I-dark) of 2.21 x 10(-8) and 3.28 x 10(-9) A, respectively, in the photocurrents (I-ph) of 1.35 x 10(-7) and 4.33 x 10(-6) A, respectively, under UV irradiation. The I-ph/I-dark ratios of ZOA-0 and ZOA-1 NRs were 6 and 1320, respectively. As a result, the adsorption of Au on ZnO NRs can increase the conductivity of UV MSM PDs and improve the responsivity of devices for UV-sensing.

Automated summary

In this study, gold nanoparticles were used to modify zinc oxide nanostructures, enhancing the performance of ultraviolet photodetectors. Single-crystalline nanorods with hexagonal wurtzite structures were obtained through a hydrothermal synthetic route, showing that adsorption of gold can increase conductivity and improve UV sensing capabilities.