Effect of Ar Gas Pressure on Mechanical Properties of Sputtered Ti Thin Films

Ti-Mg immiscible alloy thin films were prepared using a multi-arc ion plating technique with various deposition parameters. The surface and cross-section morphologies, crystal structures, and chemical compositions of the Ti-Mg films were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), and transmission electron microscopy (TEM). The influence of the substrate negative bias voltage and Ar gas pressure on the microstructure of the Ti-Mg films was systematically studied. Mg atoms were incorporated into the Ti lattice to form an FCC immiscible supersaturated solid solution phase in the thin film. Microparticles were observed on the film surface, and the number of microparticles could be significantly reduced by decreasing the substrate bias voltage and increasing the Ar gas pressure. The appropriate substrate bias voltage and Ar gas pressure increased the deposition rate. The TEM results indicated that columnar, nanolayer, and equiaxed nanocrystals were present in the thin films. Ti and Mg fluctuations were still evident in the nanoscale structures.

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Structure and Optical Properties of ZnO Thin Film Preparation Using RF Magnetron Sputtering

Materials Science Forum ◽

10.4028/www.scientific.net/msf.663-665.377 ◽

2010 ◽

Vol 663-665 ◽

pp. 377-380

Author(s):

Shan Yu Quan ◽

Lin Mei Yang ◽

Cong Liu ◽

Xu Dong Zhang

Keyword(s):

Thin Films ◽

Magnetron Sputtering ◽

Band Gap ◽

Optical Band Gap ◽

Rf Magnetron Sputtering ◽

Band Gap Energy ◽

Gas Pressure ◽

Visible Range ◽

Zno Films ◽

Ar Gas

The aim of this study is to obtain high-quality zinc oxide thin films by reactive radiofrequency (rf) magnetron sputtering. The thin films were prepared at constant total gas pressure, with different oxygen and argon contents. The ZnO samples were characterized by several methods. From XRD measurements it was confirmed that ZnO films are c-axis oriented, the line width and intensity are sensitive to O2/Ar gas pressure. All films exhibited excellent transmission (in excess of 70 %) in the visible range with a steep fall off in transmission at 425 nm. From the absorbance measurements the optical band-gap energy was extrapolated according the transmission spectrum. It shows that the optical band gap of the films increased from 3.233 eV to 3.288 eV with increase in the oxygen concentrations from 20 % to 70 %. Refractive indexes of the obtained thin films were carried out in this study.

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Effect of Ar Gas Pressure on LSPR Property of Au Nanoparticles: Comparison of Experimental and Theoretical Studies

Nanomaterials ◽

10.3390/nano10061071 ◽

2020 ◽

Vol 10 (6) ◽

pp. 1071

Author(s):

Serap Yiğit Gezgin ◽

Abdullah Kepceoğlu ◽

Yasemin Gündoğdu ◽

Sidiki Zongo ◽

Anna Zawadzka ◽

...

Keyword(s):

Thin Films ◽

Near Infrared ◽

Au Nanoparticles ◽

Wavelength Region ◽

Gas Pressure ◽

Nano Particles ◽

Au Nanoparticle ◽

Localized Surface Plasmon ◽

Ambient Gas ◽

Ar Gas

In this study, the thin films were produced by using pulsed laser deposition (PLD) technique from gold (Au) nanoparticles deposited on two kinds of substrates under different argon (Ar) gas pressure. Microscope glass slides and silicon (100) wafers were used as amorphous and crystal substrates. The films were deposited under 2 × 10−3 mbar, 1 × 10−2 mbar, 2 × 10−2 mbar argon (Ar) ambient gas pressure. Effect of the background gas pressure on the plasma plume of the ablated Au nanoparticles was investigated in details. Morphology of Au nanoparticle thin films was investigated by means of atomic force microscopy (AFM) technique. Absorption spectra of Au nanoparticles were examined by using UV-Vis spectrometry. Extinction spectra of Au nanoparticles were calculated by using metallic nano particles boundary element method (MNPBEM) simulation programme. Both experimental spectra and simulation data for Au nanoparticles were obtained and compared in this work. It was concluded that they are also in good agreement with literature data. The measurements and the simulation results showed that localized surface plasmon resonance (LSPR) peaks for Au nanoparticles were located in the near infrared region (NIR) because of the larger size of the disk-like shape of Au nanoparticles, and the near-field coupling between Au nanoparticles. It was demonstrated that as the ambient gas (Ar) pressure was increased, the size and the density of Au nanoparticles on the substrate were decreased and the LSPR peak shifts toward the short wavelength region in the spectrum. This shift has been explained by the changes in the morphology of produced thin films.

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Hydrogen Effect on Structure and Mechanical Properties of ZnO Films Deposited in Ar/H2 Plasma

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.66.156 ◽

2010 ◽

Vol 66 ◽

pp. 156-161 ◽

Cited By ~ 1

Author(s):

Ruben Bartali ◽

V. Micheli ◽

G. Gottardi ◽

I. Luciu ◽

N. Laidani

Keyword(s):

Thin Films ◽

Mechanical Properties ◽

Elastic Modulus ◽

Optical Emission ◽

Zno Thin Films ◽

Zno Films ◽

Hydrogen Effect ◽

Plasma Species ◽

Ar Gas ◽

Film Porosity

In the present work the mechanical properties of ZnO thin films, deposited on Si (100) substrates, were studied using the nanoindentation technique. ZnO thin films were deposited by radiofrequency sputtering from a ZnO target with different H2/Ar gas mixtures. During the deposition the plasma species were in-situ monitored using optical emission spectroscopy (OES). The results showed that the introduction of H2 in the plasma phase had a strong effect on the material’s hardness and elastic modulus. The measured elastic modulus values were then related to the material density to estimate the porosity of the ZnO films. We found an increased film porosity when H2 was added to the sputtering gas, from 6% to 18% in volume. Moreover we found that the porosity was correlated by the emission intensity ratio of atomic Argon on atomic Hydrogen.

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