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This study is aimed at analyzing the surface micromorphology of amorphous hydrogenated carbon layers containing nickel nanoparticles (Ni-NPs@a-C:H) within their structure, which were sputtered by co-deposition of RF-Sputtering and RF-PECVD method from acetylene gas and nickel target on glass substrates. Prepared films were then used as research material following their deposition time at three different times of 3, 7 and 13 minutes. Series of height samples were taken with the help of atomic force microscopy (AFM) operating in a non-contact mode and examined in order to determine their surface engineering characteristics. The analysis of 3-D surface texture helps to understand their essential characteristics and their implications as well as graphicalmodels and their implementation in computer simulation.

The characterization of ion beam current density distribution and beam uniformity is crucial for improving broad-beam ion source technologies. The design of the broad ion beam extraction system directly affects these two parameters, therefore, depending on the application, the design and geometry of the source is changed. In this study, the effect of the presence or the absence of a neutralization process on the ion beam density was investigated. Also, the effect of the probe bias on the ion beam current measurement was evaluated. Eventually, using a flat probe, the ion beam profiles obtained from the extraction system of the ion source (Model RFIS 60, ACECR, Iran) were measured at energies from 300 eV to 1000 eV and compared in terms of current and uniformity of the ion beam in the absence of the neutralizer. In these experiments, screen and accelerator grids with different geometries (flat and convex grids) were used for comparison purposes. According to the obtained results, the flat grids generate a higher current density while the convex grids generate a more uniform beam. Therefore, each of these grid geometries can be suitable depending on the desired application.

The aim of this research is to fabricate Ag nanoparticle assemblies forming nanolayers with different thicknesses in order to evaluate their physical properties and their 3-D (three-dimensional) surface micromorphology. Such Ag nanolayers were deposited by physical vapor deposition methods under ion-beam irradiation in argon atmosphere at room temperature. X-ray diffraction (XRD) characterizations confirmed the formation of silver nanocrystals. Using surface field parameters, which were derived from atomic force microscopy (AFM) analysis, the surface morphology of the nanolayers were described according ISO 25178-2:2012. The height and slope distribution functions, together with the autocorrelation (ACF), the height–height correlation (HHCF) and the power spectral density (PSDF) functions were determined for the different analyzed samples using linear interpolation in the horizontal direction. All samples had a fractal character with a fractal dimension of 2.54 ± 0.01 independent of the film thickness.

Theoretical study of triplet half-Heusler compound RbBaB shows that this compound is a ferromagnetic half-metal with a gap of about 1.2 eV in the bulk state. The structural, electronic, optical properties, and thermodynamic stability of all possible terminations of the (001) thin film of this compound are calculated with the full-potential linear augmented plane waves method. According to the phase diagram, it was found that the Ba-B termination is the most stable one among all terminations. The electronic study reveals the half-metallic behavior with a spin polarization of less than 100 for the two Ba-B and Rb-B terminations and the metallic property for the Rb–Ba termination. The main optical response to incident light of two Rb-B and Ba-B terminations occurred in the visible area, similar to the bulk state. Excessive amounts of e1(ω) imply the metal behavior of the Rb-B and Ba-B terminations. The e2(ω) peaks in the infrared and visible area imply the intra-band transitions. Also, the energy loss function peaks are presented at the higher ultraviolet range, indicating good optical response on the surface of these compounds at IR and visible areas.

In this study nickel–carbon (Ni–C) nanocomposite thin films composed of Ni nanoparticles with different average sizes embedded in amorphous hydrogenated carbon, were prepared through the combination of radio frequency sputtering and plasma enhanced chemical vapor deposition techniques. Such samples were used as experimental models to study the three dimensional surface morphology properties in thin films by atomic force microscopy imaging and fractal analysis over square areas of 1 μm × 1 μm. The deposition time was varied at 7, 10 and 13 min, respectively, to study changes in the properties of the obtained films. The studied samples exhibited fractal properties characterized by fractal dimensions dependent on the deposition time with values between 2.43 ± 0.01 and 2.71 ± 0.01.

In this work, the optical absorption spectra of carbon–nickel films annealed at different temperatures (300–1000 °C) with a special emphasis on the surface plasmon resonance (SPR) were investigated. The films were grown on quartz substrates by radio-frequency (RF) magnetron co-sputtering at room temperature with a deposition time of 600 s. The optical absorption peaks due to the SPR of Ni particle are observed in the wavelength range of 300–330 nm. With annealing temperature increasing up to 500 °C due to the increase in Ni particle size, the intensity of the SPR peaks increases, but weakens with annealing temperature increasing over 500 °C. The Ni nanoparticle size, the dielectric function of carbon matrix (e m) and the plasma frequency of the free electrons (ω p) at 500 °C have the maximum values of 21.63 nm, 0.471 and 5.26 × 1015 s−1, respectively. The absorption peak shows a redshift trend up to 500 °C and then turn to blueshift with annealing temperature increasing over 500 °C. These observations are in a good agreement with the electrical measurements in temperature range of 15–520 K and the Maxwell–Garnett (M–G) effective medium theory (EMT).

Thin films of Ag/Cu were deposited by reactive DC magnetron sputtering on (001)-oriented Si and glass substrates for various deposition times (4–24 min). These films were characterized by atomic force microscopy (AFM), and a power law scaling was performed on the obtained micrographs to investigate the self-affine nature of the sample morphology, which is indicative of a fractal structure. We applied the Higuchi’s algorithm to the AFM data to determine the fractal dimension of each sample, and the Hurst exponents were computed. The deposition time dependences of these parameters and the grain size distributions estimated from the UV–visible spectra using the Mie theory, allowed us to describe a particle formation mechanism during the deposition process, in which the length of continuous paths of conductive particles increases as the deposition time is increased. In agreement with this explanation, the electrical resistance decreased with the increment of the deposition time.

The preparation of designed nanostructured thin films combining nano grains of different compositions and physical properties represents a promising avenue for the exploration of novel collective behaviors with technological potentials. Herein, nanostructured Ag-Cu thin films with different surface morphology properties were grown by magnetron sputtering varying the deposition time (4-24 min) and fixing the other deposition conditions. X-ray diffraction studies corroborated that Cu and Ag tend to appear as separated phases with nanometric sizes due to the fact that these elements are rather immiscible. The deposited Cu tended to be partially oxidized with crystal sizes of several tens of nm, whereas the deposited Ag phase displayed a poor crystallinity with an average crystal size of around 3nm. However, at deposition time of few minutes, the formation of Ag-Cu crystals with a preferable crystallization orientation along the [111] direction was detected. The surface morphology of the obtained thin films was studied by atomic force microscopy determining the surface roughness and average particle sizes of the samples. These parameters were correlated with the plasmon resonance extinction bands of the different Ag-Cu films and their electrical properties, providing a reproducible route to obtain thin films with tuned electrical resistances and optical properties.