Effect of Annealing Temperature on Structural, Morphological, Optical and Electrical Properties of Spray Deposited V2O5 Thin Films

Abstract

Nanostructured vanadium pentoxide (V₂O₅) thin films have been deposited by a simple and cost-effective spray pyrolysis technique (SPT) at substrate temperature 300 °C and post annealed at atmospheric conditions in the temperature range from 300 °C to 500 °C at a constant rate of heating. The influence of post annealing heat treatment on the crystallization of V₂O₅ has been investigated. Films were characterized structurally by X-ray diffraction, morphologically by Scanning electron microscopy, optically using UV-Vis spectrophotometer, electrical characterization using Hall probe and Raman spectroscopy has been carried out for phase confirmation. X-ray diffraction analysis (XRD) revealed that, as deposited films were orthorhombic structures with a preferential orientation along (0 0 1) direction. Moreover, it was observed that crystallite size increases from 22 nm to 56 nm with increase in annealing temperature. Optical properties of these samples were studied in the wavelength range 300 – 1000 nm. Raman spectrum confirms the layered structure of V₂O₅ thin films. Hall Effect measurements indicate that the change in carrier concentration with increase in annealing temperature.