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Highlights: [•] Polyethylene naphthalate ripple pattern was successfully prepared. [•] Dimensions of nanostructures can be precisely controlled. [•] KrF excimer treatment significantly changes the PEN surface chemistry. [•] Electrically continuous gold nanopattern was constructed. [ABSTRACT FROM AUTHOR]

This work is focused on plasma treatment of polypropylene (PP) and deposition of Au layer by sputtering and evaporation. Samples were exposed to argon plasma discharge (8.3 and 3.2 W) and the changes of the surface properties were studied by different analytical methods. Surface wettability was derived from contact angle. PP was metallized with sputtered and evaporated Au layer. Surface morphology was measured with atomic force microscopy. The Au layers were deposited by sputtering and evaporation. The thickness of the deposited Au layers was determined by atomic absorption spectroscopy. The mechanical properties of deposited Au layers were analyzed using NanoIndenter device, the surface morphology of scratches in Au was studied by SEM microscopy. The significant difference in the zeta-potential at all pH range between pristine and plasma-treated PP clearly indicates the effect of plasma treatment leading to a more hydrophilic surface. The surface modification of the PP substrate, even the wettability of surface and its roughness are modified, is not capable of significant changes in substrate-metal nanoparticle interaction, since the thickness of gold nanolayers is slightly influenced by substrate premodification. Both sputtered and evaporated gold nanolayers on pristine PP become electrically conductive for thickness from ∼8 nm. POLYM. ENG. SCI., 53:2270-2275, 2013. © 2012 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Abstract: Interference effects can lead to the formation of ripple structures at laser-irradiated poly(ethylene terephthalate) surfaces. Poly(ethylene terephthalate) surface was irradiated with linearly polarized light of a pulsed 157nm laser. In a certain range of irradiation parameters, the irradiation resulted in the formation of coherent ripples patterns. The dimension of the pattern depends on the angle of the laser beam incidence. The surface morphology of the nano-patterned poly(ethylene terephthalate) was analyzed by atomic force microscopy and focused ion beam-scanning electron microscopy. Oxygen concentration in the modified polymer surface was studied by angular resolved X-ray induced photo-electron spectroscopy. Gold nano-layers were consecutively sputtered onto the laser irradiated poly(ethylene terephthalate) surfaces. The morphology of the sputtered gold nano-layers was investigated with atomic force microscopy too. We found that the morphology of the gold nano-layers changes and depends on the surface pattern of the laser irradiated poly(ethylene terephthalate). Formation of gold “nano-hills” is observed at the ridges of the ripple structures. The amount of oxygen together with the morphology of prepared polymer pattern may be the dominant factors controlling the gold layer growth. The present results are compared with those obtained earlier on PET irradiated with krypton fluoride laser. [Copyright &y& Elsevier]

This work deals with characterization of polypropylene (PP) exposed to plasma discharge and gold layers deposited on the plasma modified PP. PP foils were exposed to Ar plasma and subsequently metallized with sputtered Au layer. Chemical structure of the plasma modified PP was studied using X-ray photoelectron spectroscopy (XPS) and Rutherford backscattering (RBS). Wettability of the plasma modified PP and its changes during sample aging were determined by goniometry. Surface morphology of PP and deposited Au layers was measured with atomic force microscopy (AFM). Continuity of Au layers was characterized by measuring their sheet resistance. With increasing exposure time in the plasma discharge the water contact angle decreases and the polymer surface becomes more hydrophilic. During the aging of the plasma treated samples the contact angle increases again. Plasma treatment leads to a decrease of the PP surface roughness and to generation of oxygen-containing polar groups on PP surface. During sample aging the concentration of the oxygen-containing groups decreases. [ABSTRACT FROM AUTHOR]

Abstract: Gold nano-layers were deposited onto laser irradiated polyethyleneterephthalate (PET) surfaces. For irradiation, we used the linearly polarized light of a pulsed 248nm KrF and 157nm F2 laser, respectively. In a certain range of irradiation parameters, the irradiation resulted in the formation of coherent ripples patterns with a lateral periodicity in the order of the wavelength of the laser light and with a corrugation height of several 10nm. The deposited layers were then prepared by sputtering. The layers were analyzed by atomic force microscopy (AFM), focused ion beam (FIB) cuts, scanning electron microscopy (SEM), and angular resolved X-ray induced photoelectron spectroscopy (ARXPS). Gold sputtering on KrF laser irradiated PET led to the formation of separated “nano-wires” at the ridges of the nano-patterns and not to a continuous metal layer, as we obtained in case of gold sputtering onto F2 irradiated PET. The results of the XPS analysis indicated, that the KrF irradiation caused degradation on the ridge of the ripples, whereas no noticeable degradation occurred for F2 laser treatment. We attribute the different growth mechanisms of the deposited gold layers mainly to the difference in surface chemical composition of laser irradiated PET with the two different lasers employed. [Copyright &y& Elsevier]

Abstract: Ultrathin gold layers with different thickness of (10–100nm) on the glass substrate were obtained by Ar plasma-assisted sputtering. The effects of annealing on gold structures sputtered onto glass substrate were studied using AFM, SEM, UV–Vis methods and electrical measurements. Concentration of free charge carriers were determined from the measured resistance and the Hall constant measured by the Van der Pauw method. We have shown that post-deposition thermal treatment leads in significant change in surface morphology of the sputtered Au structures. Our results suggest that the annealing affects electrical properties of the Au coverage namely electrical sheet resistance, free carriers volume concentration, the saturation of which is in comparison with as-sputtered samples shifted towards thicker structures. While semi-conductive character of as-sputtered samples diminishes close to the Au structure thickness of ca 20nm, in the case of the annealed structures zero-level saturation is achieved for the thickness of 60nm. [Copyright &y& Elsevier]

Abstract: Polyethylene (PE) surface was treated with Ar plasma. Activated surface was grafted from methanol solution of 1,2-ethanedithiol. Then the sample was immersed into freshly prepared colloid solution of Au-nanoparticles. Finally Au layer was sputtered on the samples. Properties of the modified PE were studied using various methods: AFM, EPR, RBS and nanoindentation. It was shown that the plasma treatment results in degradation of polymer chain (AFM) and creation of free radicals by EPR. After grafting with dithiol, the concentration of free radicals declines. The presence of Au and S in the surface layer after the coating with Au-nanoparticles was proved by RBS. Plasma treatment changes PE surface morphology and increases surface roughness, too. Another significant change in surface morphology and roughness was observed after deposition of Au-nanoparticles. Nanoindentation measurements show that the grafting with Au-nanoparticles increases adhesion of subsequently sputtered Au layer. [Copyright &y& Elsevier]