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Nitrogen ions were implanted at different energies of 15, 30, 45 and 60 keV and with the flux of 1017 N+cm−2 inside the nickel layers that have been deposited on the 304 stainless steel using the electron gun method at room temperature. XRD patterns showed different crystalline phases of nickel nitride for the implanted samples. The surface morphology was extracted by MountainsMap software's using statistical data from AFM analysis. In addition, a potentiodynamic polarisation test was performed in a 3.5% NaCl solution to study the corrosion behaviour. These studies revealed that corrosion was directly related to the deposition parameters, mainly the implantation energy, modifying the surface so that the highest corrosion resistance was obtained for the sample implanted with 60 keV. [ABSTRACT FROM AUTHOR]

In this study, the morphological properties and micro‐roughness of chromium thin film prepared by thermal evaporation technique and confirmed via EDS analysis are examined on different substrates of BK7, Silicon (Si), and glass using atomic force microscope analysis (AFM). Analysis of amplitude parameters, Minkowski functionals, and films' spatial microtexture extracted from AFM analysis showed the difference between glass substrate and the other two (BK7 and Si) substrates for the growth of chromium thin films. In addition, we observed robust signatures of multifractality of the Cr thin films deposited on all substrates we studied. Moreover, we highlight that the Glass substrates displayed the strongest multifractality indicating that such samples present space filling properties distributed over more spatial scales than the samples of BK7 and Si. [ABSTRACT FROM AUTHOR]

In this work, the atomic force microscopy (AFM) technique was used to characterize 3D MgF2 thin film surfaces through advanced analysis involving morphological, fractal, multifractal, succolarity, lacunarity and surface entropy (SE) parameters, consistent with ISO 25178‐2: 2012. Samples were synthesized by electron beam deposition, grown in three different temperatures. Three different temperatures of 25°C (laboratory temperature), 150 and 300°C were chosen. The temperature of 300°C is usually the highest temperature that can be deposited with the electron beam evaporation coating system. The substrates were made of glass (diameter 16 mm, thickness 3 mm), and the samples were prepared at a pressure of 5 × 10−5 Torr. The statistical results from the AFM images indicate that topographic asperities decrease with increasing deposition temperature, showing a decrease in roughness values. Regardless of the deposition temperature, all surfaces have a self‐similar behavior, presenting a very linear PSD distribution, and, according to our results, the sample deposited at 300° had the highest spatial complexity. On the other hand, surface percolation is increasing when temperature increases, indicating that its low roughness and high spatial complexity play an important role on the formation of their most percolating surface microtexture. Our results demonstrate that the lower deposition temperature promoted the formation of less discontinuous height distributions in the MgF2 films. [ABSTRACT FROM AUTHOR]

Diamond-like carbon (DLC) coatings are mostly known for their excellent mechanical and tribological properties. However, DLC coatings also can be served as coatings with metal impurities which are attractive due to their special structural and electrical properties. In this study, silver nanoparticles are co-deposited on carbon films using RF-sputtering and RF-PECVD methods. Films are made on BK7 substrates under different working pressures (i.e., 17.5–20.5 mTorr). In this regard, according to ISO 25178–2: 2012, 2-3D Ag-DLC thin film surfaces are characterized using the atomic force microscopy method via advanced analysis implicating multifractal and morphological properties. Statistical and Minkowski functions results obtained from AFM data demonstrate that the surface topography of the films is changed by altering the deposition pressure. Based on the deposition pressure, the samples prepared at 20.5 mTorr and 19.5 mTorr have the highest and lowest values of the highest spatial complexity compared to other samples, respectively. The generalized dimension and mass exponent trend reveals the multifractal character of the studied surfaces, which the results of the multifractal study of the films are in good agreement with other AFM statistical data. In addition, with the help of EDS analysis, the presence of carbon, nitrogen, and silver elements is confirmed with different weight percentage. The damping and flattening of the surface plasmon resonance (SPR) peaks in the UV–visible absorption spectrum of the samples can be witnessed at different working pressures, which is evaluated and analyzed by AFM and EDS results. [ABSTRACT FROM AUTHOR]

Utilizing a plasma focus (PF) instrument, magnesium nitride (Mg3N2) thin films were synthesized on stainless steel substrates. Twenty five optimum focus shots at 8 cm distance from the anode tip were used to deposit the films at different angular positions regarded to the anode axis. Scanning electron microscopy (SEM), atomic force microscopy (AFM), and X‐ray diffraction (XRD) analyses were performed to assess the surface morphology and structural characteristics of Mg3N2 films. Based on AFM images, these films were studied to understand the effect of angular position variation on their surfaces through morphological and fractal parameters. By increasing the angle, we verify that the grain size decreased from 130(0) nm to 75(5) nm and also the mean quadratic surface roughness of the films reduced in its average values from (28.97 ± 3.24) nm to (23.10 ± 1.34) nm. Power spectrum density analysis indicated that films become more self‐affine at larger angles. Furthermore, the corrosion behavior of the films was investigated through a potentiodynamic polarization test in H2SO4 solution. It was found that the ion energy and flux, varying with the angular positions from the anode tip, directly affected the nanostructured roughness and surface morphology of the samples. The electrochemical studies of films show that the uncoated sample presented the lowest corrosion resistance. The highest corrosion resistance was obtained for the sample deposited with 25 optimum shots and at 0° angular position reaching a reduction in the corrosion current density of almost 800 times compared to the pure stainless steel‐304 substrate. Highlights: Mg3N2/SS films have been deposited at different angles by plasma focus (PF) instruments.The effect of angular position on the surface microtexture, morphological parameters, and corrosion features of the films was studied.The RBS measurement and X‐ray diffraction are utilized to identify the crystalline phases and thickness of films. [ABSTRACT FROM AUTHOR]

In this study, ZrO2 coatings with different thicknesses were grown by the electron beam evaporation technique. The crystalline structure was studied by XRD analysis which suggested the tetragonal and monoclinic phases for ZrO2 coatings. Additionally, the film thickness slightly enhanced the crystallinity. The surface morphology and fractal features were analyzed using Scanning Electron Microscopy (SEM). The surface statistical parameters and the fractal geometry were employed to analyze the impact of the coating thickness and homogeneity on the morphology of the films. The statistical processing and fractal dimension revealed variations in the morphology parameters due to the electron beam evaporation method applied for different thicknesses of samples. Based on these results, it can be concluded that the surface microtexture and fractal dimension area correlated with the thickness and homogeneity of the crystalline structure. [ABSTRACT FROM AUTHOR]

In this work, the atomic force microscopy (AFM) technique was used to characterize 3D MgF 2 thin film surfaces through advanced analysis involving morphological, fractal, multifractal, succolarity, lacunarity and surface entropy (SE) parameters, consistent with ISO 25178-2: 2012. Samples were synthesized by electron beam deposition, grown in three different temperatures. Three different temperatures of 25°C (laboratory temperature), 150 and 300°C were chosen. The temperature of 300°C is usually the highest temperature that can be deposited with the electron beam evaporation coating system. The substrates were made of glass (diameter 16 mm, thickness 3 mm), and the samples were prepared at a pressure of 5 × 10 -5  Torr. The statistical results from the AFM images indicate that topographic asperities decrease with increasing deposition temperature, showing a decrease in roughness values. Regardless of the deposition temperature, all surfaces have a self-similar behavior, presenting a very linear PSD distribution, and, according to our results, the sample deposited at 300° had the highest spatial complexity. On the other hand, surface percolation is increasing when temperature increases, indicating that its low roughness and high spatial complexity play an important role on the formation of their most percolating surface microtexture. Our results demonstrate that the lower deposition temperature promoted the formation of less discontinuous height distributions in the MgF 2 films., (© 2022 Wiley Periodicals LLC.)

Utilizing a plasma focus (PF) instrument, magnesium nitride (Mg 3 N 2 ) thin films were synthesized on stainless steel substrates. Twenty five optimum focus shots at 8 cm distance from the anode tip were used to deposit the films at different angular positions regarded to the anode axis. Scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray diffraction (XRD) analyses were performed to assess the surface morphology and structural characteristics of Mg 3 N 2 films. Based on AFM images, these films were studied to understand the effect of angular position variation on their surfaces through morphological and fractal parameters. By increasing the angle, we verify that the grain size decreased from 130(0) nm to 75(5) nm and also the mean quadratic surface roughness of the films reduced in its average values from (28.97 ± 3.24) nm to (23.10 ± 1.34) nm. Power spectrum density analysis indicated that films become more self-affine at larger angles. Furthermore, the corrosion behavior of the films was investigated through a potentiodynamic polarization test in H 2 SO 4 solution. It was found that the ion energy and flux, varying with the angular positions from the anode tip, directly affected the nanostructured roughness and surface morphology of the samples. The electrochemical studies of films show that the uncoated sample presented the lowest corrosion resistance. The highest corrosion resistance was obtained for the sample deposited with 25 optimum shots and at 0° angular position reaching a reduction in the corrosion current density of almost 800 times compared to the pure stainless steel-304 substrate. HIGHLIGHTS: Mg 3 N 2 /SS films have been deposited at different angles by plasma focus (PF) instruments. The effect of angular position on the surface microtexture, morphological parameters, and corrosion features of the films was studied. The RBS measurement and X-ray diffraction are utilized to identify the crystalline phases and thickness of films., (© 2022 Wiley Periodicals LLC.)