Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 5 de 5
Filter
Add more filters










Database
Language
Publication year range
1.
ACS Omega ; 9(4): 4339-4346, 2024 Jan 30.
Article in English | MEDLINE | ID: mdl-38313472

ABSTRACT

The purpose of this work is a stereometric analysis of Ni-Cu thin films to obtain the three-dimensional (3D) microtexture surface based on atomic force microscopy (AFM). Four Ni-Cu thin films on glass and silicon substrates were prepared by a capacitively coupled RF-PECVD system with a 13.56 MHz power supply. The AFM data of the samples were stereometrically analyzed, and the surface microtexture was determined according to the definition of relevant parameters in the standards ISO 25178-2:2012 and ASME B46.1-2009. All microtexture features can be implemented in numerical programs to simulate advanced microtexture models under specific microstructure and composition conditions. The results can be used to validate theoretical models for predicting or correlating the surface parameters of nanostructures. The Ni-Cu films with 40% Cu have a more irregular surface; hence, the maximum Sq value of the as-deposited Ni-Cu films is about 81.24 µm. The core roughness height Sk is calculated as a difference between two extreme levels (maximal and minimal) of the surface core, for which Ni-Cu films with 40% Cu have a maximum value of 183.4 µm. Since the surface kurtosis (Sku) of all sample films was lower than 7, there are very small peaks or valleys on the film surface and for Ni-Cu films with 5% Cu with a value of 3.568. With increasing Cu content, the height distribution histograms of films show more uniform distributions.

2.
Microsc Res Tech ; 84(6): 1098-1105, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33405274

ABSTRACT

The main goal of the present work is to explore the three dimensional (3-D) atomic force microscopy (AFM) images of human teeth and investigating their micromorphology. For this purpose, 10 fresh and permanent canine teeth were selected from a group of 40-year-old men who were candidate for the experimental processes. Afterward, they were all applied for studying the morphology of their hard tissues. The tapping mode of AFM was used to characterize the surface micromorphology on the square areas of 1 µm × 1 µm (512 × 512 pts). AFM results and surface stereometric analysis indicate the relationships between the micromorphology of the surface and the structural properties of these tissues across the length scales. As can be seen, the surface of cementum has the most irregular topography (D = 2.87 ± 0.01) while the most regular topography (D = 2.43 ± 0.01) is found in dentin. Furthermore, the more and less regularity of the surface have been found in inner enamel (Sq = 26.26 nm) and dentin (Sq = 41.28 nm), respectively. Stereometric and fractal analyses give valuable information about human canine teeth via 3-D micromorphology.


Subject(s)
Cuspid , Dental Cementum , Adult , Dental Enamel , Dentin , Humans , Male , Microscopy, Atomic Force
3.
Microsc Res Tech ; 84(6): 1205-1211, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33350550

ABSTRACT

In this article, the Ni-Cu nanoparticles (NPs) in the amorphous carbon hydrogenated thin films with different copper percentage by co-deposition of RF-plasma enhanced chemical vapor deposition were prepared using acetylene gas and Ni and Cu targets. The films deposited with 5% Cu have minimum value of the average diameter of Multi-walled Carbon Nanotubes, MWCNTs, in about of 100 nm. It can be seen that the lateral size values of the nanoparticles for films with 5% Cu have minimum value of 5.34 nm. Films deposited with 75% Cu have maximum value of optical density specially in high energy. The spectral density power of all films indicated the presence of fractal components in prominent topographies. Films deposited without Cu NPs have minimum value of fractal dimension in about of 2.96. The diagram of the bearing area versus the nanoparticles height has shown the percentage of cavities and single-layers. The single-layer contents of all films were about 95%.

4.
Microsc Res Tech ; 83(5): 457-463, 2020 May.
Article in English | MEDLINE | ID: mdl-31912934

ABSTRACT

This work describes an analysis of titanium dioxide (TiO2 ) thin films prepared on silicon substrates by direct current (DC) planar magnetron sputtering system in O2 /Ar atmosphere in correlation with three-dimensional (3D) surface characterization using atomic force microscopy (AFM). The samples were grown at temperatures 200, 300, and 400°C on silicon substrate using the same deposition time (30 min) and were distributed into four groups: Group I (as-deposited samples), Group II (samples annealed at 200°C), Group III (samples annealed at 300°C), and Group IV (samples annealed at 400°C). AFM images with a size of 0.95 µm × 0.95 µm were recorded with a scanning resolution of 256 × 256 pixels. Stereometric analysis was carried out on the basis of AFM data, and the surface topography was described according to ISO 25178-2:2012 and American Society of Mechanical Engineers (ASME) B46.1-2009 standards. The maximum and minimum root mean square roughnesses were observed in surfaces of Group II (Sq = 7.96 ± 0.1 nm) and Group IV (Sq = 3.87 ± 0.1 nm), respectively.

5.
Microsc Res Tech ; 79(12): 1208-1213, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27639345

ABSTRACT

This work analyses the three-dimensional (3-D) surface texture of carbon-nickel (C-Ni) films grown by radio frequency (RF) magnetron co-sputtering on glass substrates. The C-Ni thin films were deposited under different deposition times, from 50 to 600 s, at room temperature. Atomic force microscopy was employed to characterize the 3-D surface texture data in connection with the statistical, and fractal analyses. It has been found that up to 180 s the sputtering occurs in more metal content mode and in greater than 180 s it occurs in more non-metal content mode. This behavior demonstrated a strong link between the structural and morphological properties of C-Ni composite films and facilitates a deeper understanding of structure/property relationships and surface defects in prepared samples. Furthermore, these findings can be applied to research on the mechanisms to prepare and control high-quality C-Ni films.

SELECTION OF CITATIONS
SEARCH DETAIL
...