TY - JOUR A1 - Handrea-Haller, Marlene A1 - Sahre, Mario A1 - Neubauer, A. A1 - Sleytr, U.B. A1 - Kautek, Wolfgang T1 - Electrochemistry of Nano-Scale Bacterial Surface Protein Layers on Gold KW - S-layers crystallization KW - Gold KW - Electrochemical quartz microbalance KW - Scanning force microscopy KW - XPS PY - 2002 SN - 0013-4686 SN - 1873-3859 N1 - Geburtsname von Handrea-Haller, Marlene: Handrea, M. - Birth name of Handrea-Haller, Marlene: Handrea, M. PB - Elsevier Science CY - Kidlington AN - OPUS4-1736 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schröder, K. A1 - Meyer-Plath, Asmus A1 - Keller, D. A1 - Ohl, A. T1 - On the Applicability of Plasma Assisted Chemical Micropatterning to Different Polymeric Biomaterials N2 - A plasma process sequence has been developed to prepare chemical micropatterns on polymeric biomaterial surfaces. These patterns induce a guided localized cell layover at microscopic dimension. Two subsequent plasma steps are applied. In the first functionalization step a microwave ammonia plasma introduces amino groups to obtain areas for very good cell adhesion; the second passivation step combines pattern generation and creation of cell repelling areas. This downstream microwave hydrogen plasma process removes functional groups and changes the linkages of polymer chains at the outermost surfaces. Similar results have been obtained on different polymers including polystyrene (PS), polyhydroxyethylmethacrylate (PHEMA), polyetheretherketone (PEEK), polyethyleneterephthalate (PET) and polyethylenenaphthalate (PEN). Such a rather universal chemical structuring process could widen the availability of biomaterials with specific surface preparations. KW - Microwave plasma KW - Ammonia KW - Hydrogen KW - Polymer surface KW - Cell culture KW - XPS KW - Fluorescence PY - 2002 DO - https://doi.org/10.1023/A:1016239302194 SN - 1084-0184 SN - 1572-8978 VL - 7 IS - 2 SP - 103 EP - 125 PB - Plenum Press CY - New York, NY AN - OPUS4-1729 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gross, Thomas A1 - Unger, Wolfgang A1 - Patscheider, J. T1 - Quantitative surface chemical analysis of stainless steel 1.4301 using Surface Science Instruments XPS spectrometers: report on an interlaboratory comparison N2 - Results of an interlaboratory comparison of XPS data obtained with stainless steel are presented. Only one photoelectron spectrometer model was used. The stainless-steel sample surfaces were analysed in different states by XPS: as received, after sputtering to I(C 1s)/I(Fe 2p3/2) 0.025 and after removing a chromium-enriched oxide layer following a certain protocol. The Fe, Cr and Ni elemental concentrations were evaluated from the respective XPS data submitted by the participants of the interlaboratory test experiment. Total means, repeat standard deviations (sr) and reproducibility standard deviations (sR) are presented. The best reproducibility standard deviations were obtained for the XPS analysis after removal of a chromium-enriched oxide layer and quantification of the XPS intensities without taking the contamination elements of carbon and oxygen into account. The absolute reproducibility standard deviation of the elemental concentrations in that case is as small as 1.1-1.5 at.%. This gives 2%, 6% and 16% for the relative reproducibility standard deviation of the concentrations of iron, chromium and nickel, respectively. The total means of the iron, chromium and nickel concentrations finally obtained agree within 2sR with bulk values determined by wavelength-dispersive x-ray fluorescence spectroscopy. Comparison to an earlier interlaboratory test experiment shows that using only one model of photoelectron spectrometer reduces the reproducibility standard deviations efficiently. Copyright © 2002 John Wiley & Sons, Ltd. KW - XPS KW - ESCA KW - Quantitative surface chemical analysis KW - Stainless steel KW - Interlaboratory comparison PY - 2002 DO - https://doi.org/10.1002/sia.1229 SN - 0142-2421 SN - 1096-9918 VL - 33 IS - 5 SP - 426 EP - 432 PB - Wiley CY - Chichester AN - OPUS4-1409 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Unger, Wolfgang A1 - Gross, Thomas A1 - Lippitz, Andreas A1 - Güttler, B. T1 - Uncertainty in measurement of overlayer thickness of thermally oxidized silicon using x-ray photoelectron spectroscopy N2 - Overlayers of SiO2 (nominally 4, 6 and 8 nm thick) on silicon, prepared by thermal oxidation, were investigated using x-ray photoelectron spectroscopy (XPS). The thickness of these overlayers was obtained from a measurement of the photoelectron intensities originating from the substrate and the oxide overlayer by applying an appropriate quantitative model. The uncertainty budget of that thickness measurement method is given. The relative combined standard uncertainty of the method was found to be 15%. The effective attenuation lengths or the corresponding electron inelastic mean free paths are of considerable importance for both the estimated values of overlayer thickness and combined standard uncertainties. The XPS results were compared with ellipsometry data. KW - XPS KW - ESCA KW - Uncertainty KW - Overlayer KW - SiO2 PY - 2000 DO - https://doi.org/10.1002/1096-9918(200012)29:12<891::AID-SIA943>3.0.CO;2-A SN - 0142-2421 SN - 1096-9918 IS - 29 SP - 891 EP - 894 PB - Wiley CY - Chichester AN - OPUS4-1075 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Friedrich, Jörg Florian A1 - Koprinarov, Ivaylo A1 - Giebler, Rainer A1 - Lippitz, Andreas A1 - Unger, Wolfgang T1 - Reactions and Intermediates at the Metal-Polymer Interface as Observed by XPS and NEXAFS Spectroscopy KW - XPS KW - NEXAFS KW - Interfacial polymer-metal redox reactions KW - Chromium-polymer intermediates KW - Near edge X-ray absorption fine structure spectroscopy KW - Adhesion KW - Polymer-metal bonds KW - Polymer-aluminium bonds KW - Polymer-copper bonds PY - 1999 SN - 0021-8464 SN - 1545-5823 VL - 71 SP - 297 EP - 321 PB - Gordon & Breach CY - New York, NY AN - OPUS4-798 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -