We investigated the effect of film thickness on the structure and properties of VeN coatings deposited by magnetron sputtering in an argon and nitrogen atmosphere. The nitrogen percentage was changed between 10 and 20%. Firstly, structural and morphological properties of VeN films were observed, analyzed and subsequently followed by a detailed investigation on the mechanical and tribological properties of these coatings. It has been shown that film structure, hardness and wear resistance significantly changed with varying the film thickness and the nitrogen percentage. In the case of films deposited under 10%N 2 , the presence of V 2 N phase was evident. With increasing nitrogen ratio in the deposition chamber from 10 to 20%, the structure was changed from (hc)V 2 N to multi phases of V 2 N and (fcc) VN (formation of different vanadium nitrides). The thick films containing more nitrogen were slightly dense compared to the thinner ones presenting rough surface and columnar morphology. Nanoindentation measurements showed that film mechanical behavior depends on its thickness, nitrogen percentage and microstructural features. The film hardness first increased with its thickness and then decreased. The highest hardness of 26.2 GPa was obtained for the film deposited under 20%N 2 , which is correlated with its dense structure and film stoichiometry. The film thickness has a significant effect on the tribological properties of VeN films. The minimum friction coefficient of 0.4 was found for the thickest film of 2500 nm. The wear rate gradually decreased with increasing the film thickness, due to the high hardness, presence of VN phase and the strong adhesion between film and substrate.

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In this paper, we report the effects of Indium doping concentrations (from 0 to 10wt%) on the structural, morphological, and optical properties of deposited In doped ZnO (IZO) thin films prepared by the sol-gel method through the dip coating technique. X-ray diffraction (XRD) analysis indicates that all ZnO thin films have a polycrystalline nature with a hexagonal wurtzite phase with (002) as a preferential orientation. XRD results demonstrate that the particle size of ZnO decreased with the increase in Indium concentrations. Raman scattering spectra confirmed the wurtzite phase and the presence of intrinsic defects in our samples. Energy dispersive spectroscopy (EDS) and the X-ray photoelectron spectroscopy (XPS) measurements, confirmed the presence of zinc, oxygen and indium elements which is in agreement with XPS results. The photoluminescence (PL) spectra of the films exhibit defects-related visible emission peaks, with intensities differing owing to different concentrations of zinc vacancies. UV-Vis spectrometer measurements show that all the films are highly transparent in the visible wavelength region (≥70%) and presented two different absorption edges at about 3.21 eV and 3.7 eV, these may be correspond to the band gap of zinc oxide and indium oxide respectively.