Crystal Structure, Surface Topography, Surface Morphology and Optical Properties of DC Magnetron Sputtered VO₂ Thin Films using VO₂ Target

Abstract

Vanadium dioxide (VO2) thin films were deposited at room temperature on Corning 2947 glass substrates by direct current (DC) magnetron sputtering with a high purity VO2 target. Crystal structure, surface topography, surface morphology and optical properties of the deposited VO2 thin films were investigated. The deposited films exhibited a single orientation of (110) with a crystallite size of 41.3 nm as confirmed by the X-ray diffraction analysis and Scherrer formula, respectively. From the surface topography analysis, the film surface had root mean square surface roughness of ~6.8 nm and consisted of round-shaped grains. Similarly, from the surface morphology analysis, spherical-like grains were observed on the surface of the deposited VO2 thin films with estimated average grain size of 34.2 nm. The deposited thin films showed high transmittance and low reflectance in the visible and near-infrared wavelength regions at room temperature. In addition, from the optical transmittance against temperature measurements, only a few transmittance variation and a slight change in hysteresis loop were detected during heating and cooling between room temperature and 100 °C. Hence, the deposited VO2 thin films were found to exhibit lack of phase transition.

Fabrication of vanadium dioxide thin films and application of its thermochromic and photochromic nature in self-cleaning: A review

“…DC sputtering and RF magnetron sputtering are the most often used in the deposition of VO 2 thin films. 67 Some innovations have been made to improve these popular methods by making them dual ion assisted or RF-inverted cylindrical magnetron sputtering, producing high-quality VO 2 thin films. 103 Recently research interest has been picked in using the HiPIMS sputtering technique to deposit VO 2 thin films.…”

Effect of Ar pressure on phase transition characteristics and charge transport mechanism in VO2 films grown by RF sputtering of V2O5

“…To the best of our knowledge, this is the first time, we have attempted to grow optimum quality VO 2 films by RF magnetron sputtering of V 2 O 5 target in pure Argon (4N pure) gas atmosphere without any oxygen or postdeposition (annealing) processing. It is to be mentioned that in all the studies [29,[35][36][37], whether PLD or sputtering, the growth of VO 2 film has been carried out from the commercial oxide targets (VO 2 , V 2 O 3 , and V 2 O 5 ). But here, we have tried to optimize VO 2 thin films from a prepared V 2 O 5 target by sintering the commercial V 2 O 5 powder.…”