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Mirko Cernak - One of the best experts on this subject based on the ideXlab platform.

  • Plasma Treatment of glass surfaces using diffuse coplanar surface barrier discharge in ambient air
    Plasma Chemistry and Plasma Processing, 2013
    Co-Authors: Tomas Homola, Mirko Cernak, Jindřich Matousek, Martin Kormunda, Linda Y L Wu
    Abstract:

    We report a study on the Treatment of flat glass surfaces by ambient air atmospheric pressure Plasma, generated by a dielectric barrier discharge of coplanar arrangement of the electrode system—the diffuse coplanar surface barrier discharge (DCSBD). The Plasma Treatment of glass was performed in both static and dynamic modes. With respect to wettability of the glass surface, Treatment in static mode resulted in non-uniform surface properties, whereas dynamic mode provided a fully uniform Treatment. A water contact angle measurement was used to determine the efficiency of Plasma Treatments in dynamic mode and also to investigate a hydrophobic recovery of Plasma treated glass surfaces. The X-ray photoelectron spectroscopy measurements showed a decrease of overall carbon concentrations after Plasma Treatment. A deconvolution of C1s peak, showed that a short Plasma Treatment led to decrease of C–C bonds concentration and increases of C–O and O–C=O bond concentrations. An enhancing influence of the glass surface itself on DCSBD diffuse Plasma was observed and explained by different discharge onsets and changes in the electric field distribution.

  • influence of humidity on atmospheric pressure air Plasma Treatment of aluminium surfaces
    Applied Surface Science, 2012
    Co-Authors: Vadym Prysiazhnyi, V B Zaporojchenko, Holger Kersten, Mirko Cernak
    Abstract:

    Atmospheric pressure air Plasma Treatment of aluminium surfaces and its aging behaviour in different environments were studied. Two types of aluminium samples with different purity and surface morphology were treated using the diffuse coplanar surface barrier discharge (DCSBD). Surface free energy (SFE) and X-ray photoelectron spectroscopy (XPS) have been utilised to characterise changes induced by the Plasma. A significant decrease of hydrocarbon contaminants after the Plasma Treatment was observed. It is concluded that besides the re-contamination by exposure to ambient air, the aging effect, i.e. decrease of the surface free energy of Plasma treated surfaces, can be due by dehydration of aluminium oxide layer. Also, it was observed that the humid air Plasma Treatment resulted in generation of NOx surface groups.

Wolfgang Viöl - One of the best experts on this subject based on the ideXlab platform.

  • The effect of air Plasma Treatment at atmospheric pressure on thermally modified wood surfaces
    Wood Science and Technology, 2016
    Co-Authors: Daniela Altgen, Georg Avramidis, Wolfgang Viöl, Carsten Mai
    Abstract:

    This study tests the hypothesis that thermal modification of wood influences the effectivity of air Plasma Treatment. Micro-veneers of European beech, Scots pine and Norway spruce were thermally modified at two different temperatures and subsequently Plasma-treated for 1 and 3 s. The veneer surfaces were characterized in terms of morphology, wetting behaviour and surface chemistry. No severe changes in the veneer surfaces due to Plasma Treatment were observed by scanning electron microscopy. Plasma Treatment increased surface free energy and wettability by water and urea–formaldehyde adhesive; it was more effective on thermally modified wood than on unmodified wood. X-ray photoelectron spectroscopy revealed a similar distribution of oxygen-containing functional groups on the wood surface after Plasma Treatment of thermally modified and unmodified beech wood. It is suggested that enhanced wettability through Plasma Treatment is due to the generation of carboxyl groups within the lignin network, which contribute to the polar part of the surface free energy. The high effectiveness of Plasma Treatment on thermally modified wood might thus be explained by its high relative proportion of lignin

  • impact of air Plasma Treatment at atmospheric pressure on wood and wood extractives
    International Wood Products Journal, 2016
    Co-Authors: Georg Avramidis, Holger Militz, Richard Wascher, Wolfgang Viöl
    Abstract:

    This study addresses the question of whether the extractives or the main components of wood are responsible for the alterations in surface energy after air-Plasma Treatment. For this purpose, x-ray photoelectron spectroscopy was carried out on untreated, microtomed and air-Plasma-modified beech wood surfaces. A dielectric barrier discharge at atmospheric pressure was used for Plasma modification. The results indicate that air-Plasma Treatment affects the O/C-ratio and surface energy characteristics of wood surfaces by oxidative alteration and exposition of the wood main components.

  • influence of air Plasma Treatment at atmospheric pressure on wood extractives
    Polymer Degradation and Stability, 2012
    Co-Authors: Georg Avramidis, Holger Militz, Lothar Klarhofer, W Mausfriedrichs, Wolfgang Viöl
    Abstract:

    Abstract The influence of an atmospheric pressure Plasma Treatment on wood extractives has been investigated by means of surface energy determination and XPS. Polar and disperse component of the surface energy show only marginal influence of Plasma Treatment, whereas XPS indicates Plasma induced oxidation and degradation of the extractives.

  • sanding vs Plasma Treatment of aged wood a comparison with respect to surface energy
    International Journal of Adhesion and Adhesives, 2009
    Co-Authors: Arndt Wolkenhauer, Georg Avramidis, Evelyn Hauswald, Holger Militz, Wolfgang Viöl
    Abstract:

    To compare sanding and Plasma Treatment by dielectric barrier discharge (DBD) with respect to their effects on wood surface characteristics, beech, oak, spruce, and Oregon pine were investigated. For this purpose, the surface energy of aged, freshly sanded or Plasma-treated surfaces was examined by contact angle measurement and calculation of work of adhesion. For both methods, sanding and Plasma Treatment, an increase in surface energy caused by a heavily increased polar part was found. Plasma Treatment turned out to be superior to sanding. To see whether a combined Treatment amplified this effect, a combination of sanding and Plasma Treatment was also investigated.

  • Plasma Treatment of wood plastic composites to enhance their adhesion properties
    Journal of Adhesion Science and Technology, 2008
    Co-Authors: Arndt Wolkenhauer, Georg Avramidis, Evelyn Hauswald, Holger Militz, Wolfgang Viöl
    Abstract:

    In this study, the adhesion properties of adhesives and paints on wood–plastic composites (WPCs) after Plasma Treatment at atmospheric pressure and ambient air were investigated. Surface energy determination by means of contact angle measurements according to the Owens–Wendt approach and atomic force microscopy to detect changes in surface topography were carried out. An increase in the polar component of surface energy and an increase in surface roughness after Plasma Treatment were detected, indicating enhanced bond strength. To confirm these results, bond strength tests were conducted. By tensile bond strength tests, increased adhesion of waterborne, solventborne and oil-based paints on Plasma treated surfaces was found. Furthermore, by shear bond strength tests, an increase in bond strength of Plasma treated WPCs bonded with poly(vinyl acetate) and polyurethane adhesives was ascertained.

Hosuk Choi - One of the best experts on this subject based on the ideXlab platform.

  • novel effects of surface modification on activated carbon fibers using a low pressure Plasma Treatment
    Journal of Physical Chemistry C, 2007
    Co-Authors: Shen Tang, Ji Ku Wang, Seungkon Ryu, Hosuk Choi
    Abstract:

    Activated carbon fibers (ACFs) were surface modified with oxygen Plasma at low pressure. The novel effects of the Plasma Treatment on the microstructural properties of the ACFs were characterized using the Brunauer, Emmett, and Teller method and scanning electron microscopy. Micropores developed on the ACFs. Moreover, the specific surface area and micropore volume increased by 10% at a certain Plasma Treatment time and power. The changes in the structural properties of the ACFs are discussed in detail with the respect of Plasma etching. X-ray photoelectron spectroscopy revealed new oxygen-containing groups, such as CO, CO, and OCO, had formed on the surface of the ACFs after Plasma Treatment. Plasma surface oxidative reactions such as the generation of radicals, the combination of the radicals and active oxygen species in the Plasma chamber, and the generation of the various oxygen-containing groups are believed to have occurred. The effect of the Plasma Treatment parameters such as Plasma Treatment time ...

  • surface characteristics of aisi 304l stainless steel after an atmospheric pressure Plasma Treatment
    Surface & Coatings Technology, 2005
    Co-Authors: Shen Tang, Ohjune Kwon, Na Lu, Hosuk Choi
    Abstract:

    Abstract AISI 304L stainless steel plates were treated in an atmospheric pressure Plasma at room temperature in order to improve the surface properties. After Plasma Treatment, the contact angle test was conducted and the wettability and the surface-free energy of the stainless steel plates were both proved to be enhanced after Plasma Treatment. Through the analysis of the contact angle and surface-free energy, the optimum Plasma Treatment conditions were also obtained, including the Treatment time of 60 s, the Treatment power of 120 W and the aging time of 3 to 5 min in air. In the meanwhile, the surface roughness, morphology and chemical compositions of the stainless steel plates before and after Plasma Treatment were characterized by atomic force microscopy (AFM) and X-ray Photoelectron Spectroscopy (XPS). It was proved that the surface roughness was slightly decreased, and new functional groups—oxides and nitrides, appeared on the surface of the stainless steel after Plasma Treatment.

Raghavendra V Reddy - One of the best experts on this subject based on the ideXlab platform.

  • reduced leakage in epitaxial bifeo3 films following oxygen radio frequency Plasma Treatment
    Journal of Applied Physics, 2013
    Co-Authors: Deepti Kothari, Sanjay Kumar Upadhyay, C Jariwala, P M Raole, Raghavendra V Reddy
    Abstract:

    Epitaxial BiFeO3 (BFO) films were deposited using pulsed laser deposition method. The prepared films were characterized using x-ray diffraction, x-ray reflectivity, ferroelectric loop tracer, and leakage current measurements before and after oxygen Plasma Treatment. The leakage current of the films, a crucial parameter in device applications, is observed to be reduced by two orders of magnitude with oxygen Plasma Treatment at room temperature. P-E hysteresis loops were observed in oxygen Plasma treated BFO films. The observed results indicate the usefulness of oxygen radio frequency Plasma Treatment (RF 13.56 MHz), which is an effective and low temperature processing technique, in such lossy ferroelectric thin films.

Jongwan Park - One of the best experts on this subject based on the ideXlab platform.

  • microstructure evolution of the tanx x 0 1 diffusion barriers by nh3 Plasma Treatment for the electroless copper deposition
    Japanese Journal of Applied Physics, 2004
    Co-Authors: Seok Woo Hong, Yong Sun Lee, Jongwan Park
    Abstract:

    Microstructure evolution during NH3 Plasma Treatment of the surface of TaNx barrier films was investigated using transmission electron microscopy (TEM) in order to understand how the Plasma Treatment improves the palladium activation process for electroless copper deposition. Plan view TEM and selected area diffraction pattern (SADP) results showed that the outermost surface of the crystalline TaNx layer was transformed to the amorphous phase by the NH3 Plasma Treatment. The surface energy, evaluated by contact angle measurement, of TaNx films was increased by the NH3 Plasma Treatment. The increase in the surface energy of TaNx films by the Plasma Treatment seems to increase the nucleation sites for palladium activation. It is thought that the enhancement of the palladium activation process by the NH3 Plasma Treatment was caused by an increase in the surface energy of TaNx films during the Plasma Treatment.

  • the effect of nh 3 Plasma Treatment on the electroless copper deposition on tan x x 0 1 diffusion barriers
    Electrochemical and Solid State Letters, 2003
    Co-Authors: Seok Woo Hong, Yong Sun Lee, Jongwan Park
    Abstract:

    The effect of NH 3 Plasma Treatment of the surface of the TaN x barrier films on electroless copper deposition on TaN x films was investigated to enhance the quality of electroless Cu with the low electrical resistivity of TaN x barrier films. Electrical resistivities of TaN x barrier films were increased by less than 10% by Plasma Treatment. Auger electron spectroscopy depth profiles results showed that only a small fraction of the TaN x layer depth was affected by the Plasma Treatment. Field-emission scanning electron microscope micrographs of palladium activated TaN x films showed the number density of palladium nuclei on TaN x barriers was remarkably increased by the NH 3 Plasma Treatment. Electroless copper deposition on TaN x barriers was improved significantly by the NH 3 Plasma Treatment without a large increase in electrical resistivity.