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Oxide Substrates (oxide + substrate)
Selected AbstractsNanoscale Conducting Oxide Writing: Nanoscale Writing of Transparent Conducting Oxide Features with a Focused Ion Beam (Adv. Mater.ADVANCED MATERIALS, Issue 6 20096/2009) A conductive atomic force microscopy tip probes an embedded, optically transparent, electrically conducting oxide nanowire that was patterned on an indium oxide substrate using focused ion beam implantation. The nanowire is 160 nm wide, 7 nm deep, and theoretically limitless in length, connectivity, and shape. Nanowires of this type have potential application as interconnects in transparent electronics. Further details can be found in the article by Tobin Marks, Mark Hersam and co-workers on p.721. [source] Development and characterization of light-emitting diodes (LEDs) based on ruthenium complex single layer for transparent displaysPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 8 2008G. Santos Abstract In this work, two ruthenium complexes, [Ru(bpy)3](PF6)2 and [Ru(ph2phen)3](PF6)2 in poly(methylmethacrylate) matrix were employed to build single-layer light-emitting electrochemical cells by spin coating on indium tin oxide substrate. In both cases the electroluminescence spectra exhibit a relatively broad band with maxima near to 625 nm and CIE (x, y) color coordinates of (0.64, 0.36), which are comparable with the photoluminescence data in the same medium. The best result was obtained with the [Ru(bpy)3](PF6)2 device where the optical output power approaches 10 µW at the band maximum with a wall-plug efficiency higher than 0.03%. The lowest driving voltage is about 4 V for an electrical current of 20 mA. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] The Formation of Large-Area Conducting Graphene-Like PlateletsCHEMISTRY - A EUROPEAN JOURNAL, Issue 33 2009Riccardo Salvio Abstract The treatment of a suspension of graphite oxide (GO) with sodium azide leads to a material that, after reduction, features amino groups at the top and bottom of the sheets. These groups react through microcontact printing with an isothiocyanate monolayer on a silicon oxide substrate to form covalent bonds that strongly attach to the particles on the surface. With ultrasonication it is possible to obtain exfoliation of the sheets that are not covalently bound to the surface leaving single-layer platelets attached to the substrate. The azido derivative can be also used to functionalize the graphene oxide with long alkylic chains through a click chemistry approach. This functionalization results in the exfoliation of this material in dimethylformamide. The novel materials were fully characterized by different techniques including IR spectroscopy, thermogravimetric analysis (TGA), scanning and transmission electron microscopy (SEM and TEM), X-Ray photoelectron spectroscopy (XPS), and solid state NMR spectroscopy. The material with amino groups, after the reduction step, is conductive with a resistivity only approximately seven times larger than that of unprocessed graphite. This implies that after reduction of the GO, the conjugated sp2 network is largely restored. We consider this to be an important step towards a chemical approach for forming conducting large-area platelet films of single-layer graphene. [source] Stability of poly(3,4-ethylene dioxythiophene) materials intended for implants,JOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 2 2010Elin M. Thaning Abstract This study presents experiments designed to study the stability of the conducting polymer poly(3,4-ethylene dioxythiophene) (PEDOT), under simulated physiological conditions using phosphate-buffered saline (PBS) and hydrogen peroxide (H2O2) (0.01M) at 37°C over a 5- to 6-week period. Voltage pulsing in PBS was used as an additional test environment. The influence of switching the counter ion used in electropolymerization from polystyrene sulphonate (PSS) to heparin was investigated. Absorbance spectroscopy and cyclic voltammetry were used to evaluate the material properties. Most of the samples in H2O2 lost both electroactivity and optical absorbance within the study period, but PEDOT:PSS was found slightly more stable than PEDOT:heparin. Polymers were relatively stable in PBS throughout the study period, with around 80% of electroactivity remaining after 5 weeks, disregarding delamination, which was a significant problem especially for polymer on indium tin oxide substrates. Voltage pulsing in PBS did not increase degradation. The counter ion influenced the time course of degradation in oxidizing agents. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 2010 [source] Spin-Coating-Derived Gold-Nanoparticle MemoryJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 10 2010Ching-Chich Leu A metal,oxide,semiconductor (MOS) capacitor embedded with gold nanoparticles (Au NPs) has been successfully fabricated by a spin-coating-derived chemical solution process. The colloidal synthesized Au NPs (,3.5 nm) were self-assembled to 3-aminopropyltrimethoxysilane-modified silicon oxide substrates. With the spin-coating process, Au NPs can be fabricated onto silicon oxide with a high packing density of 1.6 × 1012 cm,2 in a short processing time. The sol,gel-derived HfO2 layer, acting as a control oxide, was also spin coated to construct an Si/SiO2/Au NPs/HfO2 structure. This MOS structure showed good memory effect and retention properties. This study indicates that it is appropriate to utilize the spin-coating process in nanocrystal memory applications. [source] Surface treatments of indium-tin oxide substrates for polymer electroluminescent devicesPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 15 2006Z. Y. Zhong Abstract In this work, three different sets of processing techniques (wet, dry, and combined treatments) were utilized to modify the surfaces of indium-tin oxide (ITO) substrates for polymer electroluminescent devices (PELDs), and the influence of surface treatments on the surface properties of ITO substrates were investigated by X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), contact angle, and four-point probe. The surface energies of ITO substrates were also calculated from the measured contact angles. Experimental results show that the surface properties of the ITO substrates strongly depend on the surface treatments. Oxygen plasma treatment effectively improves the ITO surface properties since plasma decreases the surface roughness and sheet resistance, improves the surface stoichiometry and wetting. Furthermore, the PELDs with the differently treated ITO substrates as hole-injecting electrodes were fabricated and characterized. We observe that the optical and electrical characteristics of devices are greatly influenced by the surface treatments on ITO substrates. Oxygen plasma treatment decreases turn-on voltage, increases brightness and efficiency, and thereby improves the device performance of PELDs. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Characterizations of nanostructured silicon-carbon films deposited on p-layer by PECVDPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 3-4 2010U. Coscia Abstract Nanostructured silicon carbon films composed of silicon nanocrystallites embedded in the amorphous silicon carbon matrix are prepared by a rf-PECVD system at 250 °C from silane and methane gas mixture highly diluted in hydrogen onto 7059 Corning glass and p-layer deposited on tin oxide substrates by varying rf power from 25 to 65 W. The structural and compositional properties of the films have been investigated. The study demonstrates that rf power controls the crystalline fraction as well as the silicon crystallite size and that p-layer/tin oxide structure enhances the nucleation of silicon grains as compared to Corning glass (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] | |||||||||||||