Optical constants of pulsed RF magnetron sputtered nanocolumner V2O5 coating

Vanadium pentoxide (V2O5) coatings on quartz and Si(111) substrates are grown by pulsed RF magnetron sputtering technique at constant RF power of 700 W at room temperature. Phase, microstructure and surface morphology are investigated by X-ray diffraction, field emission scanning electron microscopy and atomic force microscopy techniques, respectively. The transmittance and reflectance spectra are recorded for the solar region (200–2300 nm) of the spectral window. Further, optical constants viz. optical band gap, refractive index and extinction coefficient of the deposited V2O5 coatings are estimated. Thickness dependent optical band gaps are found in the range of 2.78–2.59 eV. Wavelength dependent characteristic is also observed both for refractive index and extinction coefficient. Finally, thickness of the present coating predicted theoretically which is matched well with the thickness measured by direct measurement e.g., nanoprofilometry technique.