Low reflectance sputtered vanadium oxide thin films on silicon

Vanadium oxide thin films on silicon (Si) substrate are grown by pulsed radio frequency (RF) magnetron sputtering technique at RF power in the range of 100-700 W at room temperature. Deposited thin films are characterized by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) techniques to investigate microstructural, phase, electronic structure and oxide state characteristics. The reflectance and transmittance spectra of the films and the Si substrate are recorded at the solar region (200-2300 nm) of the spectral window. Substantial reduction in reflectance and increase in transmittance is observed for the films grown beyond 200 W. Further, optical constants viz, absorption coefficient, refractive index and extinction coefficient of the deposited vanadium oxide films are evaluated. (C) 2016 Elsevier B.V. All rights reserved.