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ZnO thin films are synthesized by an ultrasonic spray pyrolysis method, with the deposition temperature in a range between 250–450 °C. The obtained thin films are analyzed by X‐ray diffraction (XRD), atomic force microscopy (AFM), and photoluminescence (PL). The samples are used in a photocatalytic experiment to compare the degradation efficiency by methylene blue decomposition under UV irradiation. XRD patterns confirm a polycristalline wurtzite structure with preferred orientation along the (002) plane. AFM images reveal an important change in the shape and size of the grains constituting the surface. The roughness values are in the range of 17–93 nm. Thickness values of thin films deposited at 250, 350, and 450 °C are ≈0.9, 2.3, and 1.4 µ, respectively. From PL characterization, the spectra are found to be sensitive to the deposition temperature, where emission peaks with different forms and intensities are observed. One peak at 389 nm is attributed to the recombination of free excitons, and other peaks between 403–522 nm correspond to violet, blue, and green emissions indicating the presence of Zn vacancies, Zn interstitials, and oxygen vacancies, respectively, in the ZnO structure. The photocatlytic results show that the best photocatalytic efficiency of 88% is achieved by ZnO thin film deposited at 450 °C. [ABSTRACT FROM AUTHOR]

Zirconium nitride films are deposited onto stainless steel AISI 316L and silicon (100) by radio frequency magnetron sputtering at different nitrogen flow ratios [N2/(Ar+N2)] varied between 0 and 0.25). Scanning electron microscope, atomic force microscopy, X‐ray diffraction (XRD), and Raman are used to investigate the surface morphology and microstructure of the thin films. The mechanical and electrochemical properties of all coatings are evaluated and compared with the uncoated AISI 316L to explore the efficiency of surface modification. The XRD and Raman analysis show that all the films are crystalline. This shows that the increased nitrogen content leads to a transformation from hexagonal α‐Zr phase to cubic c‐Zr and then to mixed α‐Zr and face centered cubic c‐ZrN phases. The films deposited with nitrogen flow ratio of 0.2 show the highest hardness of 32.2 GPa. Using the potentiodynamic polarization method, the corrosion behavior of the films is studied in Hank's solution. The comparison between uncoated and coated substrates shows a decrease in corrosion current density for all coated samples. [ABSTRACT FROM AUTHOR]

In order to study the influence of the substrate bias on the properties of ZrN thin films deposited by radio-frequency magnetron sputtering for biomedical application. Films of ZrN were grown onto 316L stainless steel substrate using radio-frequency (rf) magnetron sputtering from a pure zirconium target in Ar - N2 gas mixture. The substrate bias voltage was varied from 0 to −100 V, which produces a variation in the structural and electrochemical properties of the obtained films. The deposited films were characterized by X-Rays Diffraction, Atomic Force Microscopy, scanning force microscopy and potentiodynamic polarization. [ABSTRACT FROM AUTHOR]

ZrO2 thin films were deposited on 316L stainless steel substrate by a radio-frequency magnetron sputtering system. The substrate bias voltage, the working gas rate and the reactive gas fraction in the gas mixture were varied. These variations produce a variation in the deferent properties of the obtained films. The deposited films were characterized by X-Rays Diffraction, Atomic Force Microscopy, nano-indentation and potentiodynamic polarization. The experimental results show that the film thickness and the roughness of the films are highly influenced by the plasma parameters. XRD results show that the monoclinic phase is predominant in unbiased deposited films. The best anti-corrosion performance and hardness were obtained for ZrO2 deposited with a substrate bias voltage of −75 V, Ar rate of 6 sccm and oxygen fraction of 25%. [ABSTRACT FROM AUTHOR]

In this study we present the effect of negative bias applied to substrate and the pressure on the properties of TiC films (i.e. structure, Raman spectroscopy, electrical resistivity and hardness). The elaboration of our films has been carried out by RF-Magnetron Sputtering, 13.56 MHz, using two targets: titanium carbide and pure titanium. The film depositions have been done on silicon, glass and steel substrates. The total pressure was 10-60 mTorr. The attention was given to study the influence of different parameters, pressure and substrate-bias, on the properties of TiC layers. In this paper, a comparison between the properties of TiC prepared using pure titanium target and titanium carbide target is made. The deposited layers were characterized by XRD analysis, nanoindentation, four probe technique and Raman spectroscopy. [ABSTRACT FROM AUTHOR]

• ZrO 2 films were deposited on stainless steel 316L by RF magnetron sputtering. • The ZrO 2 coated 316L are hydrophobic. • Bioactivity tests in vitro demonstrate the formation of a hydroxyapatite layer on the films surface. The zirconia (ZrO 2) films were deposited using radio-frequency magnetron sputtering (RFMS) from a pure zirconium target in Ar-O 2 gas mixture with different percentage of the oxygen. The effect of Oxygen percentage on the film's characteristics was investigated by Raman spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), and tribology test. Also, the contact angle of the films was measured in order to evaluate their hydrophobicity. Additionally, in vitro test in artificial blood plasma and further SEM observations were performed to study bioactivity of the films. The experimental results showed that the roughness, the porosity and the thickness of the films depend on the oxygen percentage. According to XRD and Raman spectroscopy results, the films present a polymorph phase of monoclinic and tetragonal. Zirconia films at low oxygen percentage showed better hydrophobic behavior with 114.5° at 15% of oxygen. These films also exhibit a lower friction coefficient and wear rate (0.22 and 6 × 10−07 mm3/m respectively). However the best bioactive behavior was exhibited by the films deposited at 25% of oxygen due to their higher roughness and porosity. In fact, it was found that the bioactivity of the films is highly dependent on the porosity and roughness of the films. [ABSTRACT FROM AUTHOR]

Zirconium oxide (ZrO 2) thin films were grown onto 316L stainless steel by radio frequency magnetron sputtering (RFMS), at different substrate D.C. bias voltages (from 0 to −100 V). The deposition was performed using a pure zirconium target in the presence of an Ar-O 2 gas mixture. The characterization of the deposited films was performed using scanning Electron Microscope, atomic Force Microscopy, X-rays diffraction, Raman spectroscopy, nanoindentation and potentiodynamic polarization. The structures of all ZrO 2 films are crystalline. The monoclinic phase is predominant in the grounded films (0 V). However, the application of bias voltage depicts a tetragonal phase. Nanoindentation results reveal promoted values of the hardness of the ZrO 2 films. Corrosion behavior of the films was studied in Hank's solution using the potentiodynamic polarization method. The comparison between the uncoated samples and the coated ones showed a reduction in corrosion current density for coated samples. The minimum corrosion rate of the film deposited at −100 V was 0.04992 mpy, which is about 18 times less than that of the uncoated steel (0.88135 mpy). The optimum anti-corrosion performance and hardness were obtained for ZrO 2 deposited at a bias voltage of −100 V. • ZrO 2 films were deposited by magnetron sputtering from a metallic Zr target using oxygen as reactive gas. • ZrO 2 films with high hardness and high protective efficiency (94%) are demonstrated. • The hardness increases with the bias voltage applied to substrate. • Corrosion resistance is affected by negative bias voltage of ZrO 2 film. [ABSTRACT FROM AUTHOR]

The control of the optical properties of ZnO nanostructured thin films by using different dopant elements paves the way for the development of potential materials for photonic and optoelectronic applications. In this work manganese (Mn) doped ZnO thin films were fabricated by rapid thermal evaporation method on a glass substrate having the same Mn content level of ~10% and annealed at different temperatures. XRD analysis showed that the annealed layers have hexagonal wurtzite structure, however, the unannealed layers showed only Zn peaks without any preferential direction. The elemental analysis of the films has been investigated by XPS, which revealed the presence of Mn and oxygen atoms for all layers. In addition, it was observed by FIB-SEM that the morphology of thin films changed with the annealing temperature. For an anneal at 500 °C nanoneedles appeared. Raman spectroscopy showed E 1 (TO) mode in the sample annealed at 500 °C which was attributed with the formation of nanoneedles structures. The optical transmission of the annealed films was in the range of 75–77% and the optical bandgap varied from 3.97 to 3.72 eV. These variations are related to the structural and morphological changes of the thin films with annealing temperature. • The effect of thermal annealing on the physical properties of nanostructured Mn doped ZnO thin films was investigated. • XRD analysis revealed that MZO layers after annealing crystallize in hexagonal wurtzite phase. • The morphology of MZO films changed with the annealing temperature. For an anneal at 500 °C nanoneedles appeared. • Raman measurements have also shown an additional mode E 1 (TO) at 467 cm−1 associated with the apparition of nanoneedles. • The optical constants n, α and the thickness d were successfully identified and determined only from the transmittance spectra using the PSO algorithm. [ABSTRACT FROM AUTHOR]