Preparation of WO_3 Nanorods by Glancing Angle DC Reactive Magnetron Sputtering Deposition for NO_2 gas sensing application

摘要

In this study, we present a tungsten trioxide (WO_3) nanorods based gas sensor for NO_2 sensing at operating temperature range 150-350 °C in purify dry air carrier. WO_3 nanorods were fabricated by dc reactive magnetron sputtering with glancing angle deposition (GLAD) technique on silicon (100) wafer and alumina substrates interdigitated with gold electrode. The length of WO_3 nanorods was varied from 370 nm to 620 nm. As-deposited nanorods were annealed at a temperature of 400 °C in air for 1 h. The microstructure and phase structure of WO_3 nanorod were characterized by X-ray diffraction (XRD) and field-emission scanning electron microscopy (FE-SEM), respectively. XRD of annealed WO_3 nanorod showed polycrystalline phase. The WO_3 nanorods length 420 nm exhibit excellent NO_2 sensing properties with a maximum sensitivity of 360 at 250 °C operating temperature with fast response and recovery time.