A new, simple and highly versatile method for the surface modification of luminescent cadmium selenide nanoparticles (CdSe NPs) based on 1,3-dipolar cycloaddition reactions is described. Uniform, trioctylphosphine oxide (TOPO)-covered CdSe NPs were prepared and subjected to two ligand-exchange reactions: first, ligand exchange was accomplished with pyridine, fully removing the TOPO ligand from the CdSe surface. In a second step, either 1-[(3-azidopropyl)octylphosphinoyl]octane or hex-5-ynoic acid 3-(dioctylphosphinoyl)propyl ester were added, attaching an azido or an acetylene moiety to the NP surface. Further thermal or Cu(I)-mediated 1,3-dipolar cycloaddition reactions on the residual azido/acetylene moieties with a variety of acetylenes/azides furnished the modified CdSe NPs with supramolecular receptors (i.e. barbituric acid, thymine, oligoethyleneglycol) on their surface. Photoluminescence measurements reveal a y50% residual quantum yield (relative to TOPO-covered CdSe NPs) after ligand modification, thus presenting an efficient pathway towards luminescent, surface modified CdSe NPs. The presence of the different functional groups was proven by 1 H-NMR, 31 P-NMR spectroscopy and by use of a nanoparticle-bound spiropyran dye and subsequent fluorescence quenching experiments. In order to further exploit the ligands on the CdSe NP surfaces, supramolecular recognition via binding to self-assembled monolayers (SAMs) presenting the matching receptor was investigated, leading to dense layers of CdSe NPs on planar surfaces as verified by AFM measurements. The concept offers a simple method for guiding the binding and recognition of luminescent CdSe NPs and related NPs onto surfaces.

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We report on the deposition of nanoparticles onto polymeric surfaces by use of a multiple hydrogen bonding interaction. Main interest concerned the preparation of statistical copolymers with a defined number of interactions within the side chain, thus enabling control of the number of supramolecular interactions present on the surface for the subsequent binding-process. Thus, statistical copolymers of poly(oxy)norbornenes bearing either perfluorinated side chains or the "Hamilton receptor" in amounts ranging from 1 to 70 mol % were prepared using a ROMP methodology combined with subsequent azide/alkine "click" reactions. Films cast from these polymersseither via spin-or via dip-coatingswere used to study the binding of barbituric acid-functionalized Au nanoparticles (diameter ) 5 nm) bearing the matching supramolecular interaction toward the Hamilton receptor on the polymeric surface. A detailed AFM analysis of the films was performed, detailing the influence of filmcasting conditions on the properties of the final polymeric films. A strong effect on the bound density of the NP's was observed only at lower concentrations (below 1 mol %) of the supramolecular receptor, whereas higher amounts of receptor units exhibit only minor effects on the density of bound nanoparticles. Thus, the presented method offers the generation of polymeric films with a defined density of nanoparticles bound to their surfaces.

The investigation and analysis of polymer thin films with Bi(n)(+), n = 1-7 cluster ions has been demonstrated by means of static secondary ion mass spectrometry (SIMS). The highly specific signal enhancement of these primary ions combined with the individual fragmentation pattern of poly(4-vinylphenol) and poly(methyl methacrylate) is the basic principle for a modified approach of data reduction derived from the well-established g-SIMS procedure. Based on mass spectra, which correspond to different cluster ion sizes, not only a clear distinction between the two polymers is feasible but also a further simplification of the data can be demonstrated. It has been successfully proven that characteristic polymer-relevant species can be refined out of the large amount of unspecific and highly fragmented secondary ions, which are usually present in SIMS spectra. Therefore, a more precise and direct interpretation of complex organic fragments becomes feasible, which consequently enables the investigation of even more sophisticated samples.

ZrO 2 / GeO 2 dielectrics are grown on germanium substrates by Atomic Layer Deposition (ALD) at substrate temperatures of 150, 200, and 250 °C, respectively. The impact of the deposition temperature on the electrical and structural properties of MOS capacitors is investigated. A significant influence of the ALD temperature on the high frequency capacitance in inversion can be observed, resulting in a shift of the minority carrier response time from 1.15 to 0.2 μs. Time-of-flight secondary ion mass spectroscopy investigations indicate a distinctive depletion of interfacial GeO at higher ALD temperatures, which give rise to trap levels near the oxide/Ge interface.