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Here we report for the first time the combined nanoindentation experiments and finite element modeling to investigate the in-depth nanomechanical behavior of ~1.25 μm indium tin oxide (ITO) film. The ITO film is grown on silicon substrate by a reactive direct current (DC) magnetron sputtering technique. Here, the contributions of both film and substrate are considered in a power law based nonlinear material model. Based on experimental data a detailed study is carried out in the present work to investigate the stress–strain behavior, the related von-Mises stress and equivalent plastic strain of the ITO film. In addition, the effect of the nanoindentation response of the ITO film on the silicon substrate is also evaluated. [ABSTRACT FROM AUTHOR]

Vanadium pentoxide (V 2 O 5 ) 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 V 2 O 5 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. [ABSTRACT FROM AUTHOR]

Vanadium oxide films, deposited on aluminium (Al), titanium (Ti) and tantalum (Ta) metal substrates by pulsed RF magnetron sputtering at a working pressure of 1.5 x10−2 mbar at room temperature are found to display mixed crystalline vanadium oxide phases viz., VO2, V2O3, V2O5. The films have been characterized by field-emission scanning electron microscopy, X-ray diffraction, differential scanning calorimetry (DSC) and X-ray photoelectron spectroscopy, and their thermo-optical and electrical properties have been investigated. Studies of the deposited films by DSC have revealed a reversible-phase transition found in the temperature range of 45–49 °C. [ABSTRACT FROM AUTHOR]

Molybdenum doped vanadium oxide film on quartz and silicon substrates are grown by pulsed RF magnetron sputtering method. Surface morphology, phase analysis and oxide states are investigated by field emission scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy techniques, respectively. Crystalline nature of the film deposited on both quartz and silicon are depicted. The transmittance and reflectance spectra recorded for the entire solar region. Further, optical constants viz. optical band gap and refractive index of the deposited films are estimated. Wavelength dependent low reflectance characteristic is observed for the deposited film on silicon. IR emittance (εIR) and sheet resistance (Rs) of the film are also evaluated. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Vanadium oxide-molybdenum oxide (VO-MO) thin (21-475 nm) films were grown on quartz and silicon substrates by pulsed RF magnetron sputtering technique by altering the RF power from 100 to 600 W. Crystalline VO-MO thin films showed the mixed phases of vanadium oxides e.g., V2O5, V2O3 and VO2 along with MoO3. Reversible or smart transition was found to occur just above the room temperature i.e., at ~45-50 °C. The VO-MO films deposited on quartz showed a gradual decrease in transmittance with increase in film thickness. But, the VO-MO films on silicon exhibited reflectance that was significantly lower than that of the substrate. Further, the effect of low temperature (i.e., 100 °C) vacuum (10−5 mbar) annealing on optical properties e.g., solar absorptance, transmittance and reflectance as well as the optical constants e.g., optical band gap, refractive index and extinction coefficient were studied. Sheet resistance, oxidation state and nanomechanical properties e.g., nanohardness and elastic modulus of the VO-MO thin films were also investigated in as-deposited condition as well as after the vacuum annealing treatment. Finally, the combination of the nanoindentation technique and the finite element modeling (FEM) was employed to investigate yield stress and von Mises stress distribution of the VO-MO thin films. [ABSTRACT FROM AUTHOR]