TY - JOUR A1 - Ludwig, M. H. A1 - Augustin, A. A1 - Hummel, R. E. A1 - Gross, Thomas T1 - On the formation process of luminescing centers in spark-processed silicon KW - Silikon, funkenerodiert KW - Röntgenphotonspektroskopie KW - Photoluminiszenz PY - 1996 SN - 0021-8979 SN - 1089-7550 VL - 80 IS - 9 SP - 5318 EP - 5324 PB - American Institute of Physics CY - Melville, NY AN - OPUS4-638 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gross, Thomas A1 - Treu, Dieter A1 - Unger, Wolfgang T1 - Standard operating procedure (SOP) for the quantitative determination of organic silicon compounds at the surface of elastomeric sealants N2 - Elastomeric sealants may contain organic silicon compounds. The use of these sealants for housings for electronic components is harmful for the reliability of electric contacts inside. In order to prevent electronic components from malfunction, quality control of elastomeric sealants is required. An analytical procedure developed to fulfil this requirement was developed. It is based on electron spectroscopy for chemical analysis (ESCA). Information on the silicon compounds existing at the surface of elastomeric sealants is provided by this method. Silicon in organic and inorganic compounds can be differentiated with the help of Si 2p photoelectron spectra. Quantitative results can be obtained too. The uncertainty budget of the quantitative procedure is estimated. T2 - 11th Conference on Applied Surface Analysis (AOFA) CY - Leipzig, Germany DA - 2000-09-24 KW - ESCA KW - Silicone KW - Standard operation procedure PY - 2001 SN - 0169-4332 SN - 1873-5584 VL - 179 IS - 1-4 SP - 109 EP - 112 PB - North-Holland CY - Amsterdam AN - OPUS4-977 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Unger, Wolfgang A1 - Lippitz, Andreas A1 - Gross, Thomas A1 - Friedrich, Jörg Florian A1 - Wöll, Ch. A1 - Nick, L. T1 - The Use of Octadecyltrichlorosilane Self-Assembled Layers as a Model for the Assessment of Plasma Treatment and Metallization Effects on Polyolefins N2 - Self-assembled octadecyltrichlorosilane (CH3(CH2)17SiCl3, OTS) films were deposited on an oxidized silicon wafer. They were carefully exposed to a low-pressure oxygen direct current (dc) plasma and/or Cr vapor. Subsequently, they were characterized by X-ray photoelectron spectroscopy, near-edge X-ray absorption fine structure spectroscopy, and atomic force microscopy. Detailed information on the oxygen functionalization and the molecular conformation of the OTS films was obtained. The main result was that functionalization conditions can be found where the order of the film remains almost unaffected. Similarly, Cr evaporation of pure OTS films revealed only slight effects on the order in the film. Cr evaporation of an ordered but functionalized OTS film immediately changes its state toward a fully isotropic one. In the course of interaction, oxygen sites at the surface of the functionalized OTS film are reduced whereas Cr becomes oxidized. A redox reaction scheme is proposed for this interfacial reaction. Finally, it is concluded that the given study should be of importance for advanced plasma processing of polyolefins. KW - NEXAFS KW - OTS Self-Assembled Layers PY - 1999 U6 - https://doi.org/10.1021/la981174l SN - 0743-7463 SN - 1520-5827 VL - 15 IS - 4 SP - 1161 EP - 1166 PB - American Chemical Society CY - Washington, DC AN - OPUS4-808 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Brzezinka, Klaus-Werner A1 - Gross, Thomas A1 - Unger, Wolfgang A1 - Ramm, M. A1 - Ata, M. T1 - Studies of amorphous carbon using X-ray photoelectron spectroscopy, near-edge X-ray-absorption fine structure and Raman spectroscopy KW - Amorphous materials KW - Carbon KW - Plasma processing and deposition KW - Structural properties PY - 1999 SN - 0040-6090 VL - 354 SP - 106 EP - 110 PB - Elsevier CY - Amsterdam AN - OPUS4-891 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gross, Thomas A1 - Retzko, Iris A1 - Friedrich, Jörg Florian A1 - Unger, Wolfgang T1 - Time-of-flight-SIMS and XPS characterization of metal doped polymers N2 - Organic thin films with defined chemical structures and physical properties are required for various applications. Plasma polymerization is of technological interest, since the deposition of plasma polymers is possible on any material of any shape in the desired thickness. We report on the TOF-SIMS (TOF: time-of-flight) and XPS investigations of pulse plasma ‘poly(acetylene)’ and alkali metal doped pulse plasma ‘poly(acetylene)’ films. The combination of TOF-SIMS and XPS supplies detailed information on the surface chemistry of these films. Application of both methods provides the possibility for cross-checking certain results. Moreover the different sensitivities of the methods can be utilized. According to the TOF-SIMS and XPS data it can be concluded that the interaction of alkali metals with plasma ‘poly(acetylene)’ results in electrovalent bonds of the type Me?+–C?- between carbon and metal. Furthermore carbon–oxygen–metal interactions were observed. These interactions are of the type C=O?-cdots, three dots, centeredMe?+ and/or C–O?-–Me?+. KW - SIMS KW - TOF-SIMS KW - XPS KW - Plasma KW - Polymer KW - Poly(acetylene) PY - 2003 U6 - https://doi.org/10.1016/S0169-4332(02)00769-9 SN - 0169-4332 SN - 1873-5584 VL - 203-204 SP - 575 EP - 579 PB - North-Holland CY - Amsterdam AN - OPUS4-2271 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 U6 - 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 - 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 U6 - 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 - Österle, Werner A1 - Griepentrog, Michael A1 - Gross, Thomas A1 - Urban, Ingrid T1 - Chemical and microstructural changes induced by friction and wear of brakes N2 - The chemical and microstructural changes occurring during braking simulation tests at the surface of a conventional brake pad material were investigated mainly by scanning and transmission electron microscopy and surface analytical techniques. It can be shown that patches of a third body material develop, comprising a compositional mix of all constituents of the pad and iron oxides from the disk. Milled debris particles still have the crystal structure of barite, the major phase of the pad material, but the grain size is reduced drastically to the nanometer scale. The major wear mechanism is delamination of filler particles from the organic binder, supported by local degradation of the phenolic resin during asperity heating. Quartz crystals are preserved thereby adopting the function of primary contact areas. KW - Brake KW - Third body material KW - Friction layer KW - Electron microscopy PY - 2001 U6 - https://doi.org/10.1016/S0043-1648(01)00785-2 SN - 0043-1648 VL - 251 SP - 1469 EP - 1476 PB - Elsevier CY - Amsterdam AN - OPUS4-2371 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Unger, Wolfgang A1 - Gross, Thomas A1 - Böse, Olaf A1 - Fritz, Thomas A1 - Gelius, U. T1 - Fortschritte im Qualitätsmanagement der Oberflächenanalytik PY - 2000 U6 - https://doi.org/10.1002/nadc.20000480920 SN - 1439-9598 SN - 1521-3854 VL - 48 IS - 9 SP - 1108 EP - 1111 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-6831 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gross, Thomas A1 - Unger, Wolfgang T1 - Quantitative Bestimmung von organischen Si-Verbindungen auf Elastomeroberflächen PY - 1999 SN - 0948-3276 SN - 0022-9520 VL - 52 IS - 12 SP - 842 PB - Hüthig CY - Heidelberg AN - OPUS4-6832 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -