TY - JOUR A1 - Rades, Steffi A1 - Hodoroaba, Vasile-Dan A1 - Salge, T. A1 - Wirth, Thomas A1 - Lobera, M.P. A1 - Labrador, R.H. A1 - Natte, Kishore A1 - Behnke, Thomas A1 - Gross, Thomas A1 - Unger, Wolfgang T1 - High-resolution imaging with SEM/T-SEM, EDX and SAM as a combined methodical approach for morphological and elemental analyses of single engineered nanoparticles N2 - The combination of complementary characterization techniques such as SEM (Scanning Electron Microscopy), T-SEM (Scanning Electron Microscopy in Transmission Mode), EDX (Energy Dispersive X-ray Spectroscopy) and SAM (Scanning Auger Microscopy) has been proven to be a powerful and relatively quick characterization strategy for comprehensive morphological and chemical characterization of individual silica and titania nanoparticles. The selected “real life” test materials, silica and titania, are listed in the OECD guidance manual as representative examples because they are often used as commercial nanomaterials. Imaging by high resolution SEM and in the transmission mode by T-SEM allows almost simultaneous surface and in-depth inspection of the same particle using the same instrument. EDX and SAM enable the chemical characterization of bulk and surface of individual nanoparticles. The core–shell properties of silica based materials are addressed as well. Titania nominally coated by silane purchased from an industrial source has been found to be inhomogeneous in terms of chemical composition. KW - surface and in-depth inspection KW - silica nanoparticles KW - titania nanoparticles PY - 2014 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-316296 DO - https://doi.org/10.1039/c4ra05092d SN - 2046-2069 VL - 4 IS - 91 SP - 49577 EP - 49587 PB - RSC Publishing CY - London AN - OPUS4-31629 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bütefisch, S. A1 - Weimann, T. A1 - Busch, I. A1 - Danzebrink, H.-U. A1 - Gross, Thomas A1 - Unger, Wolfgang A1 - Wirth, Thomas T1 - New reference material for imaging XPS (X-ray photoelectron spectroscopy) instrument characterization N2 - Reference materials without variations in topography are essential for the characterization of imaging XPS (X-ray Photoelectron Spectroscopy) Instruments. Therefore a new fabrication process for this kind of zero-topography reference material was developed at PTB and resulted in first prototypes. The fabrication process and first measurement results will be presented in this paper. T2 - Sensor 2015 - 17th International conference on sensors and measurement technology CY - Nuremberg, Germany DA - 19.05.2015 KW - Imaging XPS KW - Reference material KW - Topography free KW - Micro technology PY - 2015 SN - 978-3-9813484-8-4 DO - https://doi.org/10.5162/sensor2015/P7.1 SP - Chapter P7, 821 EP - 825 AN - OPUS4-33837 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dietrich, Paul A1 - Horlacher, T. A1 - Gross, Thomas A1 - Wirth, Thomas A1 - Castelli, R. A1 - Shard, A.G. A1 - Alexander, M. A1 - Seeberger, P. H. A1 - Unger, Wolfgang T1 - Surface analytical characterization of carbohydrate microarrays N2 - Microarrays are a versatile platform for diagnostics and high-throughput analysis. Carbohydrate microarrays are valuable tools to investigate interactions with other molecules since many glycans are involved in fundamental biological processes. A combined X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) surface analysis was used to investigate the basic steps in the production of carbohydrate microarrays. The preparation included coupling of a thiol-terminated mannoside to maleimide-functionalized glass surfaces derived from γ-aminopropyl silane (GAPS) slides. XPS results clearly demonstrate successful chemical modification in each fabrication step, and ToF-SIMS imaging revealed immobilized carbohydrates in the spotted regions of the final microarray. KW - Carbohydrates KW - Microarrays KW - XPS KW - ToF-SIMS KW - Nona-mannoside KW - Maleimide surfaces KW - Surface analysis PY - 2010 DO - https://doi.org/10.1002/sia.3255 SN - 0142-2421 SN - 1096-9918 VL - 42 SP - 1188 EP - 1192 PB - Wiley CY - Chichester AN - OPUS4-21500 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Baytekin, H. Tarik A1 - Wirth, Thomas A1 - Gross, Thomas A1 - Sahre, Mario A1 - Unger, Wolfgang A1 - Theisen, J. A1 - Schmidt, M. T1 - Surface analytical characterization of micro-fluidic devices hot embossed in polymer wafers: Surface chemistry and wettability N2 - Recently, time-of-flight secondary ion mass spectrometry (ToF-SIMS) and X-ray photoelectron spectroscopy (XPS) instrumentation has been used to address areas of interest within micro-fluidic devices providing full access to the surface chemistry established at the bottom of micro-channels therein. After careful calibration, information on surface chemistry as obtained by ToF-SIMS or XPS can be interpreted in terms of wettability expressed as contact angles which are then characteristic for the inner walls of micro-channels. Standard contact angle measurement is not applicable in micro-channels. The approach has been demonstrated to be successful with two different micro-fluidic devices hot embossed into high-end quality poly(methyl methacrylate) (PMMA) or Polycarbonate wafers. A pre-selected surface chemistry at micro-channel walls can be established by plasma technologies but ageing and rinsing effects have to be under control. A combination of ToF-SIMS, XPS and contact angle measurement techniques has been demonstrated to provide the required information. Finally, it is shown by ToF-SIMS and XPS analysis that in the production of micro-fluidic parts during practical processing using hot embossing technologies, material originating from cover foils will reside on the polymer wafer's surface. Moreover, residues of releasing agents as silicone oil used during processing can be detected by ToF-SIMS. Both cover foil residues and silicones are issues of trouble shooting in micro-fluidics because they will change contact angles efficiently. KW - Micro-fluidic device KW - PMMA KW - Polycarbonate KW - Plasma treatment KW - Wettability KW - ToF-SIMS KW - XPS PY - 2010 DO - https://doi.org/10.1002/sia.3149 SN - 0142-2421 SN - 1096-9918 VL - 42 IS - 8 SP - 1417 EP - 1431 PB - Wiley CY - Chichester AN - OPUS4-21712 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Baytekin, H.T. A1 - Wirth, Thomas A1 - Gross, Thomas A1 - Treu, Dieter A1 - Sahre, Mario A1 - Theisen, J. A1 - Schmidt, M. A1 - Unger, Wolfgang T1 - Determination of wettability of surface-modified hot-embossed polycarbonate wafers used in microfluidic device fabrication via XPS and ToF-SIMS N2 - The wettability of the surfaces inside the microchannels of a microfluidic device is an important property considering a liquid flows through them. Contact angle measurements usually applied to test the wettability of surfaces cannot be used for an analysis of microchannel walls within microfluidic devices. A workaround is the use of surface analytical methods, which are able to reach points of interest in microchannels and may provide information on the surface chemistry established there. In calibrating these methods by using flat polymer wafers, where the contact angle can be measured as usual, data measured in real microchannels can be evaluated in terms of wetting properties. Reference wafers of bisphenol-A polycarbonate, a polymeric material that is often used in fluidic microdevice fabrication, were treated under different oxygen plasma conditions. The modified surfaces were characterized by using XPS, time of flight (ToF)-SIMS and atomic force microscope (AFM). Surface chemistry and surface topography have been correlated with contact angle measurements. In addition, effects of ageing or rinsing after plasma treatment have also been investigated. KW - Oxygen plasma KW - Polycarbonate KW - XPS KW - ToF-SIMS KW - Principal component analysis PY - 2008 DO - https://doi.org/10.1002/sia.2724 SN - 0142-2421 SN - 1096-9918 VL - 40 IS - 3-4 SP - 358 EP - 363 PB - Wiley CY - Chichester AN - OPUS4-17340 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dietrich, Paul A1 - Horlacher, T. A1 - Girard-Lauriault, Pierre-Luc A1 - Gross, Thomas A1 - Lippitz, Andreas A1 - Min, Hyegeun A1 - Wirth, Thomas A1 - Castelli, R. A1 - Seeberger, P. H. A1 - Unger, Wolfgang T1 - Adlayers of dimannoside thiols on gold: surface chemical analysis N2 - Carbohydrate films on gold based on dimannoside thiols (DMT) were prepared, and a complementary surface chemical analysis was performed in detail by X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (ToF-SIMS), near-edge X-ray absorption fine structure (NEXAFS), FT-IR, and contact angle measurements in order to verify formation of ω-carbohydrate-functionalized alkylthiol films. XPS (C 1s, O 1s, and S 2p) reveals information on carbohydrate specific alkoxy (C–O) and acetal moieties (O–C–O) as well as thiolate species attached to gold. Angle-resolved synchrotron XPS was used for chemical speciation at ultimate surface sensitivity. Angle-resolved XPS analysis suggests the presence of an excess top layer composed of unbound sulfur components combined with alkyl moieties. Further support for DMT attachment on Au is given by ToF-SIMS and FT-IR analysis. Carbon and oxygen K-edge NEXAFS spectra were interpreted by applying the building block model supported by comparison to data of 1-undecanethiol, poly(vinyl alcohol), and polyoxymethylene. No linear dichroism effect was observed in the angle-resolved C K-edge NEXAFS. KW - Carbohydrates KW - Self-assembled monolayer KW - XPS KW - NEXAFS KW - ToF-SIMS KW - Surface chemical analysis PY - 2011 DO - https://doi.org/10.1021/la104038q SN - 0743-7463 SN - 1520-5827 VL - 27 IS - 8 SP - 4808 EP - 4815 PB - American Chemical Society CY - Washington, DC AN - OPUS4-23554 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weigel, W. A1 - Unger, Wolfgang A1 - Graf, Nora A1 - Gross, Thomas A1 - Wirth, Thomas T1 - Surface Chemical Analysis of DNA Microarrays - Application of XPS and ToF-SIMS for Surface Chemical Imaging on the µm Scale KW - Microarrays KW - Oberflächenanalytik KW - XPS KW - ToF-SIMS KW - Chemical imaging PY - 2008 SN - 1611-597X VL - 12 IS - 10 SP - 14 EP - 16 PB - GIT-Verlag CY - Darmstadt AN - OPUS4-18307 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Graf, Nora A1 - Gross, Thomas A1 - Wirth, Thomas A1 - Weigel, W. A1 - Unger, Wolfgang T1 - Application of XPS and ToF-SIMS for surface chemical analysis of DNA microarrays and their substrates N2 - The chemical composition of the functional surfaces of substrates used for microarrays is one of the important parameters that determine the quality of a microarray experiment. In addition to the commonly used contact angle measurements to determine the wettability of functionalized supports, X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) are more specific methods to elucidate details about the chemical surface constitution. XPS yields information about the atomic composition of the surface, whereas from ToF-SIMS, information on the molecular species on the surface can be concluded. Applied on printed DNA microarrays, both techniques provide impressive chemical images down to the micrometer scale and can be utilized for label-free spot detection and characterization. Detailed information about the chemical constitution of single spots of microarrays can be obtained by high-resolution XPS imaging. KW - Microarrays KW - Surface analysis KW - XPS KW - ToF-SIMS KW - Chemical imaging PY - 2009 DO - https://doi.org/10.1007/s00216-009-2599-x SN - 1618-2642 SN - 1618-2650 VL - 393 IS - 8 SP - 1907 EP - 1912 PB - Springer CY - Berlin AN - OPUS4-19245 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hinze, A. A1 - Klages, C.-P. A1 - Zänker, A. A1 - Thomas, M. A1 - Wirth, Thomas A1 - Unger, Wolfgang T1 - ToF-SIMS imaging of DBD-plasma-printed microspots on BOPP substrates N2 - Imaging ToF-SIMS has been applied to characterize the surface chemistry variations across small areas produced by a DBD-type plasma printing technique on a BOPP substrate using pure nitrogen and a nitrogen-hydrogen gas mixture. CH4N+ and CNO- secondary ions are detected with high yields remote from the discharge region. They are discussed to be due to surface modifications of the substrate by metastable gas-phase species. On the other hand, surface species exist that are preferentially formed by reactions of the substrate with short-lived species which are only present close to the plasma discharge region. A C3H8O+ secondary fragment ion is assumed to be a key fragment of such a surface species. KW - ToF-SIMS KW - Plasma KW - Polymer KW - Dielectric barrier discharges (DBD) KW - Plasma printing KW - Polymer modification KW - Surface modification KW - Time-of-flight secondary-ion mass spectroscopy (ToF-SIMS) imaging PY - 2008 DO - https://doi.org/10.1002/ppap.200700138 SN - 1612-8850 SN - 1612-8869 VL - 5 IS - 5 SP - 460 EP - 470 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-19342 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dietrich, Paul A1 - Horlacher, T. A1 - Girard-Lauriault, Pierre-Luc A1 - Gross, Thomas A1 - Lippitz, Andreas A1 - Min, Hyegeun A1 - Wirth, Thomas A1 - Castelli, R. A1 - Seeberger, P. A1 - Unger, Wolfgang T1 - Multimethod chemical characterization of carbohydrate-functionalized surfaces N2 - A combined XPS, NEXAFS, and ToF-SIMS chemical surface characterization of carbohydrate-functionalized gold and glass surfaces is presented. Spot shape and chemical composition across a spot surface are provided by surface-sensitive methods as ToF-SIMS and XPS, used in their imaging modes. Moreover, the feasibility of this multimethod approach to control relevant production steps of a carbohydrate microarray prototype is demonstrated. KW - Carbohydrates KW - Microarrays KW - Self-assembled monolayers KW - XPS KW - NEXAFS KW - ToF-SIMS PY - 2011 DO - https://doi.org/10.1080/07328303.2011.615181 SN - 0732-8303 VL - 30 IS - 4-6 SP - 361 EP - 372 PB - Taylor & Francis CY - London [u.a.] AN - OPUS4-24874 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Girard-Lauriault, P.-L. A1 - Dietrich, Paul A1 - Gross, Thomas A1 - Wirth, Thomas A1 - Unger, Wolfgang T1 - Chemical characterization of the long-term ageing of nitrogen-rich plasma polymer films under various ambient conditions N2 - Nitrogen rich plasma polymer films (L-PPE:N) were prepared by low-pressure RF plasma using a 1:1 mixture of ethylene and ammonia and aged for 345 d in four different ambient conditions: (i) at room temperature (RT) in air; (ii) at RT in nitrogen; (iii) at -20?°C in air and; (iv) at –20 °C in nitrogen. The films were analyzed by X-ray photoelectron spectroscopy (XPS) and by time-of-flight secondary ion mass spectrometry (ToF-SIMS) at various intervals over the duration of the experiment. The ageing of primary amines, NH2, was followed by chemical derivatization with 4-trifluoromethyl benzaldehyde. Storage at –20 °C, mostly independently of ambient atmosphere, slowed down ageing to almost undetectable levels as evaluated by the analytical methods used for this study. KW - Ageing KW - Plasma polymers KW - Primary amines KW - ToF-SIMS KW - XPS PY - 2013 DO - https://doi.org/10.1002/ppap.201200118 SN - 1612-8850 SN - 1612-8869 VL - 10 IS - 4 SP - 388 EP - 395 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-28006 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Beck, Uwe A1 - Fritz, Thomas A1 - Gamer, Nadja A1 - Wirth, Thomas T1 - VAMAS - Versailles Project on Advanced Materials and Standards N2 - Glühentladung optischer Ausstrahlungsspektroskopie (GDOES) wurde ursprünglich für die elementare Analyse von Größenmaterialien entwickelt. Mehrere Gruppen führten diese Methode zur Analyse von Anstrichen, Laienstapeln und dünnen Filmen durch. In den frühen Neunzigern wurde eine ISO-TC 201-Arbeitsgruppe gegründet, um Normen für alle Formen der Glühentladungsspektroskopie (GDS) zu entwickeln und die Fähigkeiten der Oberflächenchemikalien-Analyse zu beurteilen, insbesondere für die Tiefe von gestuften Systemen. Die Quantifizierung von Tiefenprofilen, d.h. die Umwandlung von Intensitäts-Zeit- Profilen in Konzentrierungs-Tiefen-Profile ist für dc-mode entwickelt worden. 1997 wurde ein VAMAS TWA 2 Vorschlag für ein Referenzanstrich für GD-OES Tiefe gemacht. Entsprechend dem VAMAS Beurteilungsverfahren wurde dieser Vorschlag 1998 mit einigen geringfügigen Änderungen genehmigt. T3 - BAM Forschungsberichtreihe - 242 PY - 2001 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-2083 SN - 978-3-89701-713-X SN - 0938-5533 VL - 242 SP - 1 EP - 64 PB - Wirtschaftsverlag NW CY - Bremerhaven AN - OPUS4-208 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sobol, Oded A1 - Böllinghaus, Thomas A1 - Wirth, Thomas A1 - Unger, Wolfgang A1 - Eliezer, D. T1 - High resolution ToF-SIMS imaging of deuterium permeation and cracking in duplex stainless steels N2 - Fundamental understanding and elucidation of hydrogen assisted degradation and trapping mechanisms is dependent on sufficient imaging techniques for respective hydrogen interactions, in particular with multi-phase metallic microstructures. The present work shows the progress in elucidating the deuterium behavior in austenitic-ferritic duplex stainless steels under the consideration that deuterium behaves in many ways similarly to hydrogen. A novel combination of deuterium permeation and in-situ Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) imaging technique is compared with post charging ToF-SIMS imaging experiments. As a step beyond state-of-the-art, integration of chemo-metric and high resolution structural characterization techniques with computational multivariate data analysis (MVA) and data fusion is presented. T2 - 2016 International Hydrogen Conference CY - Grand Teton National Park, Jackson Lake Lodge, Wyoming, USA DA - 11.09.2016 KW - DSS KW - ToF-SIMS KW - Data-fusion KW - EBSD PY - 2017 SN - 978-0-7918-6138-7 SP - 407 EP - 415 PB - ASME Press CY - Two Park Ave. New-York, NY 10016, USA AN - OPUS4-42647 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Holzweber, Markus A1 - Sobol, Oded A1 - Wirth, Thomas A1 - Böllinghaus, Thomas A1 - Unger, Wolfgang T1 - Deuterium permeation and cracking in duplex steels as viewed by ToF-SIMS and HR-SEM with data fusion N2 - Better understanding of hydrogen assisted degradation and trapping mecha-nisms requires sufficient imaging techniques for respective hydrogen-microstructure interaction studies, in particular with multi-phase metallic micro-structures [1]. The present work is focusing on the elucidation of deuterium be-havior in two austenitic-ferritic duplex stainless steels (DSS) under the assumption that deuterium behaves in many ways similarly to hydrogen [2]. For case studies standard 2205 and lean 2101 DSSs were chosen due to the extensive use of these steels in industry [3]. The analyses were conducted by using a novel in-situ permeation and Time-of-Flight secondary ion mass spectrometry (ToF-SIMS) imaging technique or by ex-situ ToF-SIMS imaging following electrochemical charging experiments. Another pioneering procedure was data fusion (including chemometry) of results of powerful laterally resolved chemical analysis and high resolution structural characterization techniques . Results for the ex-situ observations showed a different influence of deuterium loading on the two steel grades as well as different damage mechanisms in each phase. Formation of sub-surface blisters between the ferrite and austenite were obtained in both the standard and the lean DSS. In both steels, an increased deuterium concentration was observed around deformed regions such as cracks, confirming that they originate from the presence of deuterium [4]. The formation of parallel cracks was obtained only in the austenite within the standard duplex whereas in the lean duplex the highest intensity of deuterium was obtained in the austenite along the ferrite-austenite interphase. In comparison, application of the novel in-situ permeation technique enabled to register and record the deuterium permeation through the material and the respective saturation sequence of the two phases as well as the interfaces. Faster diffusion of the deuterium was observed in the ferrite and a direct proof for deuterium enrichment at the austenite-ferrite interface has been given [1]. The integration of the specified techniques gives a better insight into the processes leading to hydrogen induced failure. These two experimental techniques provide very valuable tools for elucidation of respective metallurgical failure mechanisms that can be used for the validation of respective numerical models for hydrogen assisted cracking (HAC). T2 - 19. Arbeitstagung Angewandte Oberflächenanalytik CY - Soest, Germany DA - 05.09.2016 KW - ToF-SIMS KW - Hydrogen assisted cracking KW - Data fusion KW - SEM PY - 2016 AN - OPUS4-37484 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Straub, Franka A1 - Wirth, Thomas A1 - Hertwig, Andreas A1 - Hodoroaba, Vasile-Dan A1 - Unger, Wolfgang A1 - Böllinghaus, Thomas T1 - Imaging the microstructure of duplex stainless steel samples with TOF-SIMS N2 - Time-of-flight secondary ion mass spectrometry (TOF-SIMS) mappings provide a visualization of the distribution of chemical elements and phases on polished duplex steel surfaces as element and fragment secondary ion signals. The advantage of TOF-SIMS, compared to optical microscopy, is its potential to analyze the chemical composition with a lateral resolution at a submicrometer scale. TOF-SIMS mappings allow distinguishing between ferritic and austenitic phases because of the phase selective detection method without any requirement of etching or other processing. KW - TOF-SIMS mappings KW - Duplex stainless steel KW - Surface analysis KW - Ferritic phase KW - Austenitic phase PY - 2010 UR - http://onlinelibrary.wiley.com/doi/10.1002/sia.3385/pdf DO - https://doi.org/10.1002/sia.3385 SN - 0142-2421 SN - 1096-9918 VL - 42 IS - 6-7 SP - 739 EP - 742 PB - Wiley CY - Chichester AN - OPUS4-21818 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kim, K.J. A1 - Kim, J.W. A1 - Moon, D.W. A1 - Wirth, Thomas A1 - Hodoroaba, Vasile-Dan A1 - Gross, Thomas A1 - Unger, Wolfgang A1 - Jordaan, W. A1 - Staden, M.v. A1 - Prins, S. A1 - Wang, H. A1 - Song, X. A1 - Zhang, L. A1 - Fujimoto, T. A1 - Kojima, I. T1 - Final report on key comparison K67 and parallel pilot study P108: measurement of composition of a thin Fe-Ni alloy film N2 - The Key Comparison K67 and the parallel Pilot Study P108 on quantitative analysis of thin alloy films have been completed in the Surface Analysis Working Group (SAWG) of the Consultative Committee for Amount of Substance (CCQM). The aim of these inter-laboratory comparisons is to determine the degree of equivalence in the measurement capability of national metrology institutes (NMIs) and designated institutes (DIs) for the determination of the composition of thin alloy films. The measurand is expressed in atomic percent. A Fe-Ni alloy film with a certified composition was available for the participants of the inter-laboratory comparison. It has been used as a reference specimen to determine the relative sensitivity factors (RSF) of Fe and Ni for the different analytical methods used by the participants to determine the composition of the test sample. As was shown in the preceding Pilot Study P98, the degrees of equivalence in the measurement capabilities of the participants can be improved in that way. The composition of the reference specimen was certified by inductively coupled plasma mass spectrometry (ICP-MS) using the isotope dilution method. The in-depth and lateral homogeneity, determined in terms of elemental composition, of the certified reference sample and the unknown test sample were confirmed by secondary ion mass spectrometry (SIMS) using C60 primary ions by the leading laboratory. Five laboratories participated in the key comparison. Four of them used x-ray photoelectron spectroscopy (XPS) and one Auger electron spectroscopy (AES). One laboratory participated in the parallel P108 pilot study using electron probe micro analysis with an energy-dispersive spectrometer (ED EPMA) and XPS. KW - XPS KW - AES KW - EDX KW - Fe-Ni alloy film KW - Key comparison KW - CCQM PY - 2010 DO - https://doi.org/10.1088/0026-1394/47/1A/08011 SN - 0026-1394 SN - 1681-7575 VL - 47 IS - 1A SP - 08011-1 - 08011-15 PB - Inst. of Physics Publ. CY - Bristol AN - OPUS4-21045 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kim, K.J. A1 - Unger, Wolfgang A1 - Kim, J.W. A1 - Moon, D.W. A1 - Gross, Thomas A1 - Hodoroaba, Vasile-Dan A1 - Schmidt, Dieter A1 - Wirth, Thomas A1 - Jordaan, W. A1 - van Staden, M. A1 - Prins, S. A1 - Zhang, L. A1 - Fujimoto, T. A1 - Song, X.P. A1 - Wang, H. T1 - Inter-laboratory comparison: quantitative surface analysis of thin Fe-Ni alloy films N2 - An international interlaboratory comparison of the measurement capabilities of four National Metrology Institutes (NMIs) and one Designated Institute (DI) in the determination of the chemical composition of thin Fe-Ni alloy films was conducted via a key comparison (K-67) of the Surface Analysis Working Group of the Consultative Committee for Amount of Substance. This comparison was made using XPS (four laboratories) and AES (one laboratory) measurements. The uncertainty budget of the measured chemical composition of a thin alloy film was dominated by the uncertainty of the certified composition of a reference specimen which had been determined by inductively coupled plasma mass spectrometry using the isotope dilution method. Pilot study P-98 showed that the quantification using relative sensitivity factors (RSFs) of Fe and Ni derived from an alloy reference sample results in much more accurate result in comparison to an approach using RSFs derived from pure Fe and Ni films. The individual expanded uncertainties of the participants in the K-67 comparison were found to be between 2.88 and 3.40 atomic %. The uncertainty of the key comparison reference value (KCRV) calculated from individual standard deviations and a coverage factor (k) of 2 was 1.23 atomic %. KW - Quantification KW - Fe-Ni alloy KW - Uncertainty KW - Key comparison KW - Traceability PY - 2012 DO - https://doi.org/10.1002/sia.3795 SN - 0142-2421 SN - 1096-9918 VL - 44 IS - 2 SP - 192 EP - 199 PB - Wiley CY - Chichester AN - OPUS4-24505 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sobol, Oded A1 - Straub, F. A1 - Wirth, Thomas A1 - Holzlechner, G. A1 - Böllinghaus, Thomas A1 - Unger, Wolfgang T1 - Real Time Imaging of Deuterium in a Duplex Stainless Steel Microstructure by Time-of-Flight SIMS N2 - For more than one century, hydrogen assisted degradation of metallic microstructures has been identified as origin for severe technical component failures but the mechanisms behind have not yet been completely understood so far. Any in-situ observation of hydrogen transport phenomena in microstructures will provide more details for further elucidation of these degradation mechanisms. A novel experiment is presented which is designed to elucidate the permeation behaviour of deuterium in a microstructure of duplex stainless steel (DSS). A hydrogen permeation cell within a TOF-SIMS instrument enables electrochemical charging with deuterium through the inner surface of the cell made from DSS. The outer surface of the DSS permeation cell exposed to the vacuum has been imaged by TOF-SIMS vs. increasing time of charging with subsequent chemometric treatment of image data. This in-situ experiment showed evidently that deuterium is permeating much faster through the ferrite phase than through the austenite phase. Moreover, a direct proof for deuterium enrichment at the austenite-ferrite interface has been found. KW - Characterization and analytical techniques KW - Corrosion KW - Imaging technique KW - Mass spectrometry PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-353872 UR - http://www.nature.com/articles/srep19929 DO - https://doi.org/10.1038/srep19929 SN - 2045-2322 VL - 6 IS - 19929 SP - 1 EP - 7 PB - nature publishing group CY - London, United Kingdom AN - OPUS4-35387 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sobol, Oded A1 - Holzlechner, Gerald A1 - Nolze, Gert A1 - Wirth, Thomas A1 - Eliezer, D. A1 - Böllinghaus, Thomas A1 - Unger, Wolfgang T1 - Time-of-Flight secondary ion mass spectrometry (ToF-SIMS) imaging of deuterium assisted cracking in a 2205 duplex stainless steel microstructure N2 - In the present work, the influence of deuterium on the microstructure of a duplex stainless steel type EN 1.4462 has been characterized by Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) supported by scanning electron microscopy (SEM), focused ion beam (FIB), electron back scattered diffraction(EBSD) and energy dispersive x-ray (EDX) investigations. Characterization has been carried out before and after electrochemical charging with deuterium which has been used as a tracer, due to its similar behavior to hydrogen in the steel microstructure. In a first approach, the distribution of the deuterium occurring at temperatures above 58 °C has been visualized. Further it turned out that sub-surface micro blisters are formed in the ferrite-austenite interface, followed by the formation of needle shaped plates and subsequent cracking at the ferrite surface. In the austenite phase, parallel cracking alongside twins and hexagonal close packed (martensitic) regions has been observed. In both phases and even in the apparent interface, cracking has been associated with high deuterium concentrations, as compared to the surrounding undamaged microstructure. Sub-surface blistering in the ferrite has to be attributed to the accumulation and recombination of deuterium at the ferrite-austenite interface underneath the respective ferrite grains and after fast diffusing through this phase. Generally, the present application of chemometric imaging and structural analyses allows characterization of hydrogen assisted degradation at a sub-micron lateral resolution. KW - ToF-SIMS KW - Hydrogen assisted cracking KW - Hydrogen embrittlement KW - SEM KW - FIB KW - EBSD PY - 2016 UR - http://www.sciencedirect.com/science/article/pii/S0921509316310334 DO - https://doi.org/10.1016/j.msea.2016.08.107 SN - 0921-5093 VL - 676 SP - 271 EP - 277 PB - Elsevier B.V. AN - OPUS4-37298 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rades, Steffi A1 - Wirth, Thomas A1 - Unger, Wolfgang T1 - Investigation of silica nanoparticles by Auger electron spectroscopy (AES) N2 - High-priority industrial nanomaterials like SiO2, TiO2, and Ag are being characterized on a systematic basis within the framework of the EU FP7 research project NanoValid. Silica nanoparticles from an industrial source have been analyzed by Auger electron spectroscopy. Point, line, and map spectra were collected. Material specific and methodological aspects causing the special course of Auger line scan signals will be discussed. KW - Nanoparticles KW - Auger electron spectroscopy KW - Surface analysis PY - 2014 DO - https://doi.org/10.1002/sia.5378 SN - 0142-2421 SN - 1096-9918 VL - 46 IS - 10-11 SP - 952 EP - 956 PB - Wiley CY - Chichester AN - OPUS4-31604 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Streeck, C. A1 - Wirth, Thomas A1 - Unger, Wolfgang A1 - Beckhoff, B. T1 - Qualifying calibration samples for advanced thin film materials characterisation N2 - In this article the question of the certification of calibration samples for the characterisation of advanced thin film materials is addressed within the framework of reliable process control or quality management purposes. Reference measurement techniques can be used in order to address the gap in appropriate certified reference materials (CRMs) for thin film analyses. They allow for qualifying out-of-production samples originating from an operating production line as calibration samples. As a template for this procedure, CIGS [Cu(In,Ga)Se2] layers, that are absorber layers for high efficiency thin-film solar cells, have been used for establishing and validating reference-free X-ray fluorescence (XRF) analysis and Auger-electron spectroscopy (AES) as reference measurement techniques. The focus was on determining the average mole fractions in the CIGS layers obtaining results traceable to the SI unit system. Reference-free XRF is physically traceable and is based upon radiometrically calibrated instrumentation and knowledge of atomic fundamental data. Sputter-assisted AES can be established as a chemically traceable method after careful calibration using a certified reference material (CRM) based on a total number counting method. KW - CIGS KW - X-ray fluorescence (XRF) KW - Auger-electron spectroscopy (AES) PY - 2018 UR - https://www.spectroscopyeurope.com/article/qualifying-calibration-samples-advanced-thin-film-materials-characterisation VL - 30 IS - 1 SP - 11 EP - 14 PB - John Wiley & Sons Ltd CY - Chichester, West Sussex PO19 8SQ, UK AN - OPUS4-44260 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Unger, Wolfgang A1 - Senoner, Mathias A1 - Wirth, Thomas A1 - Bütefisch, S. A1 - Busch, I. T1 - Lateral resolution delivered by imaging surface-analytical instruments as SIMS, AES and XPS: Application of the BAM-L200 Certified Reference Material and related ISO Standards N2 - The certified reference material BAM-L200, a nanoscale stripe pattern for length calibration and specification of lateral resolution, is described. BAM-L200 is prepared from a cross-sectioned epitaxially grown layer stack of AlxGa1-xAs and InxGa1 xAs on a GaAs substrate. The surface of BAM-L200 provides a flat pattern with stripe widths ranging down to 1 nm. Calibration distances, grating periods and stripe widths have been certified by TEM with traceability to the length unit. The combination of gratings, isolated narrow stripes and sharp edges of wide stripes offers a plenty of options for the determination of lateral resolution, sharpness and calibration of length scale at selected settings of imaging surface analytical instruments. The feasibility of the reference material for an analysis of the lateral resolution is demonstrated in detail by evaluation of ToF-SIMS, AES and EDX images. Other applications developed in the community are summarized, too. BAM-L200 fully supports the implementation of the revised International Standard ISO 18516 (in preparation) which is based on knowledge outlined in the Technical Report ISO/TR 19319:2013. KW - Standardization KW - AES KW - XPS KW - SIMS KW - Lateral resolution KW - Certified reference material PY - 2017 SN - 1341-1756 VL - 24 IS - 2 SP - 123 EP - 128 AN - OPUS4-43138 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kraffert, K. A1 - Karg, M. A1 - Schmack, R. A1 - Clavel, G. A1 - Boissiere, C. A1 - Wirth,, Thomas A1 - Pinna, N. A1 - Kraehnert, R. T1 - Stabilization of Mesoporous Iron Oxide Films against Sintering and Phase Transformations via Atomic Layer Deposition of Alumina and Silica N2 - The stabilization of crystal phases and nanostructured morphologies is an essential topic in application-driven design of mesoporous materials. Many applications, e.g. catalysis, require high temperature and humidity. Typical metal oxides transform under such conditions from a metastable, low crystal-line material into a thermodynamically more favorable form, i.e. from ferrihy-drite into hematite in the case of iron oxide. The harsh conditions induce also a growth of the crystallites constituting pore walls, which results in sintering and finally collapse of the porous network. Herein, a new method to stabi-lize mesoporous templated metal oxides against sintering and pore collapse is reported. The method employs atomic layer deposition (ALD) to coat the internal mesopore surface with thin layers of either alumina or silica. The authors demonstrate that silica exerts a very strong influence: It shifts hematite formation from 400 to 600 °C and sintering of hematite from 600 to 900 °C. Differences between the stabilization via alumina and silica are rationalized by a different interaction strength between the ALD material and the ferrihydrite film. The presented approach allows to stabilize mesoporous thin films that require a high crystallization temperature, with submonolayer quantity of an ALD material, and to apply mesoporous materials for high temperature applications. KW - Mesoporous oxides KW - Atomic layer deposition KW - Stabilization PY - 2018 DO - https://doi.org/10.1002/admi.201800360 VL - 5 IS - 14 SP - 1800360-1 EP - 1800360-9 PB - Wiley-VCH AN - OPUS4-47869 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wirth, Thomas T1 - Investigation of Silica Nanoparticles by Auger Electron Spectroscopy (AES) T2 - PHI European User Meeting 2014 CY - Ismaning, Germany DA - 2014-05-14 PY - 2014 AN - OPUS4-32947 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Graf, Nora A1 - Yegen, E. A1 - Lippitz, Andreas A1 - Treu, Dieter A1 - Wirth, Thomas A1 - Unger, Wolfgang T1 - Optimization of cleaning and aminosilanization protocols for Si wafers to be used as platforms for biochip microarrays by surface analysis (XPS, ToF-SIMS and NEXAFS spectroscopy) N2 - It is known that aminosilanized Si wafers may be used as microarray platforms. Results of an XPS study of a cleaning applied to Si wafers prior to aminosilanization are presented and discussed. Furthermore, the results of an aminosilanization protocol optimized in terms of nitrogen chemistry are described. After optimization of the protocol a free amine content of 94% was reached. The surface chemistry was investigated in this study by using XPS, time of flight (ToF)-SIMS and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. Reference to aminosilanization protocols reported in the literature has been made. KW - Aminosilanization KW - Si wafers KW - Microarray KW - XPS KW - ToF-SIMS KW - NEXAFS PY - 2008 DO - https://doi.org/10.1002/sia.2621 SN - 0142-2421 SN - 1096-9918 VL - 40 IS - 3-4 SP - 180 EP - 183 PB - Wiley CY - Chichester AN - OPUS4-17192 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Senoner, Mathias A1 - Wirth, Thomas A1 - Unger, Wolfgang T1 - Imaging surface analysis: Lateral resolution and its relation to contrast and noise N2 - Lateral resolution, also called image resolution, is the most relevant quality parameter of maps and line scans. Therefore well defined procedures for the determination of lateral resolution are required. In the surface analysis community different definitions of lateral resolution are in use and there is no generally accepted method for the determination of lateral resolution which meets the demands of the state-of-the-art in surface analysis. We propose the determination of lateral resolution by imaging of well defined square-wave gratings with finely graded periods. This method enables the real time estimation of lateral resolution and the adjustment of instrument settings with respect to lateral resolution. The effect of noise and contrast on lateral resolution has been analysed by numerically simulated images of square-wave gratings. A new resolution criterion has been developed which is based on the dip-to-noise ratio and takes into account the sampling step width by introducing a "reduced noise". The contrast transfer function has been introduced and its relation to lateral resolution in the presence of noise was analysed. For that reason an "effective cut-off frequency" was defined which is the reciprocal of the lateral resolution. Normalized values of lateral resolution and their relation to signal-to-noise ratio and sampling step width were given for Gaussian and Lorentzian line spread functions. These values enable the calculation of experimental parameters which are necessary to get a required value of lateral resolution. Finally the successful application of the proposed approach to determine lateral resolution has been demonstrated by ToF-SIMS element mapping of the certified reference material BAM-L200. KW - Auflösungskriterium KW - BAM-L200 KW - Effektive cut-off Funktion KW - Laterale Auflösung KW - Kontrast KW - Kontrasttransferfunktion KW - Linienverwaschungsfunktion KW - Rauschen PY - 2010 DO - https://doi.org/10.1039/c004323k SN - 0267-9477 SN - 1364-5544 VL - 25 SP - 1440 EP - 1452 PB - Royal Society of Chemistry CY - London AN - OPUS4-21875 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Senoner, Mathias A1 - Wirth, Thomas A1 - Unger, Wolfgang A1 - Österle, Werner A1 - Kaiander, I. A1 - Sellin, R.L. A1 - Bimberg, D. T1 - BAM-L002 - A new type of certified reference material for length calibration and testing of lateral resolution in the nanometre range N2 - A new type of test sample for the determination of lateral resolution in surface analysis is presented. The certified reference material BAM-L002 Nanoscale strip pattern for length calibration and testing of lateral resolution is an embedded cross-section of epitaxially grown layers of AlxGa1-xAs and InxGa1-xAs on GaAs substrate. The surface of the sample provides a flat pattern with strip widths of 0.4-500 nm. The combination of gratings, isolated narrow strips and sharp edges of wide strips offers improved possibilities for the calibration of a length scale, the determination of lateral resolution and the optimization of instrument settings. The feasibility of the reference material for an analysis of lateral resolution is demonstrated for SIMS. PY - 2004 DO - https://doi.org/10.1002/sia.1936 SN - 0142-2421 SN - 1096-9918 VL - 36 SP - 1423 EP - 1426 PB - Wiley CY - Chichester AN - OPUS4-4696 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wirth, Thomas T1 - Development of GD-OES standard measurement procedures by using PVD and other referencecoating samples T2 - Expert-Meeting "Depth Profiling", EU Network "Analytical GDS" CY - Dresden, Germany DA - 1999-10-13 PY - 1999 AN - OPUS4-6055 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wirth, Thomas T1 - Standard-Messverfahren, Referenzmaterialien für die GD-OES, Aktivitäten der BAM T2 - 7. Deutsches Anwendertreffen "Analytische GDS" CY - Dresden, Germany DA - 2000-10-17 PY - 2000 AN - OPUS4-6122 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wirth, Thomas T1 - Development of reference materials for GD-OES, SNMS, AES and Electron Beam Microanalysis: First results of the VAMAS project, the EC project "MICROLITE" and new EC - "Expression of needs" T2 - EC Network "Analytical GDS": Expert meetings "reference materials for non-conducting and layered samples", Standard procedures; European standards CY - Berlin, Germany DA - 2000-05-03 PY - 2000 AN - OPUS4-6095 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wirth, Thomas T1 - Electron-probe MICROanalysis of LIghT Elements; Measurement Methods and Certified Reference Materials (MICROLITE) - Minutes of Progress Meeting: WP1.2 Production of carbide and nitride standards and WP1.4 Stability testing T2 - MICROLITE 7th Progress Meeting, EKO Stahl CY - Eisenhüttenstadt, Germany DA - 2001-10-17 PY - 2001 AN - OPUS4-6901 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wirth, Thomas T1 - Electron-probe MICROanalysis of LIghT Elements; Measurement Methods and Certified Reference Materials (MICROLITE) - Minutes of Progress Meeting: WP1.2 Production of carbide and nitride standards and WP1.4 Stability testing T2 - MICROLITE 6th Progress Meeting CY - Palmones, Spain DA - 2001-03-16 PY - 2001 AN - OPUS4-6902 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hantsche, Harald A1 - Golze, Manfred A1 - Zabinski, A. A1 - Eckardt, Jürgen A1 - Wirth, Thomas A1 - Schmidt, Dieter T1 - Auger microprobe-surface analysis of sub-mum nitrides and carbonitrides in steel PY - 1993 SN - 0937-0633 VL - 346 SP - 29 EP - 36 PB - Springer CY - Berlin AN - OPUS4-6903 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Senoner, Mathias A1 - Wirth, Thomas A1 - Unger, Wolfgang T1 - A reference material for calibration and testing of instruments with nanometric lateral resolution T2 - SIMS Europe 2002 ; 3rd European Workshop on Secondary Ion Mass Spectrometry CY - Münster, Germany DA - 2002-09-15 PY - 2002 SP - 58 AN - OPUS4-6841 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Almagro, J.-F. A1 - Busch, P. A1 - Gohil, D. D. A1 - Saunders, S. R. J. A1 - Sloof, W. G. A1 - Thiot, J.-F. A1 - Schneider, H. A1 - Whitwood, M. A1 - Wirth, Thomas T1 - Electron-Probe MICROanalysis of LighT Elements - Measurement Methods and Certified Reference Materials (MICROLITE) PY - 2000 IS - 266 SP - 1 EP - 35 PB - National Physical Laboratory CY - Teddington, Middlesex AN - OPUS4-6843 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Senoner, Mathias A1 - Wirth, Thomas A1 - Unger, Wolfgang A1 - Österle, Werner A1 - Kaiander, I. A1 - Sellin, R. L. A1 - Bimberg, D. ED - Wilkening, G. ED - Koenders, L. T1 - Testing the Lateral Resolution in the Nanometre Range with a New Type of Certified Reference Material T2 - NanoScale 2004 Seminar ; 6th Seminar on Quantitative Microscopy ; 2nd Seminar on Nanoscale Calibration Standards and Methods CY - Braunschweig, Germany DA - 2004-03-25 KW - Laterale Auflösung KW - Nanometrologie KW - Nanotechnologie KW - Oberflächenanalytik KW - Zertifiziertes Referenzmaterial PY - 2004 SN - 3-527-40502-X DO - https://doi.org/10.1002/3527606661.ch21 SP - 282 EP - 294 PB - Wiley-VCH CY - Weinheim AN - OPUS4-7541 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Oran, Umut A1 - Ünveren, Ercan A1 - Wirth, Thomas A1 - Unger, Wolfgang T1 - Poly-dimethyl-siloxane (PDMS) contamination of polystyrene (PS) oligomers samples: a comparison of time-of-flight static secondary ion mass spectrometry (TOF-SSIMS) and X-ray photoelectron spectroscopy (XPS) results N2 - Pure and PDMS contaminated PS oligomers films were investigated both by time-of-flight static secondary ion mass spectrometry (TOF-SSIMS) and X-ray photoelectron spectroscopy (XPS). The secondary ion spectra from the PDMS contaminated PS oligomers were almost completely related to PDMS. XPS revealed a PDMS contamination characterized by a silicon surface concentration of 6 at.%. Obviously siloxane contaminants existing on the surface of a silicon wafer may diffuse towards the PS oligomers outermost surface resulting in a rather high PDMS surface concentration of about 85%. Due to the known differences in the information depth and sensitivity of SSIMS and XPS very different detection limits are to be considered. In elimination of siloxane contaminants by ultrasonication in hexane was found to be an effective way. Another common organic cleaning procedure, which is ultrasonication in trichloroethylene (TCE), subsequently in isopropanol and finally in acetone was found to be ineffective for cleaning of PDMS contaminated silicon wafers. KW - PDMS KW - TOF-SIMS KW - Polystyrene KW - Segregation PY - 2004 DO - https://doi.org/10.1016/j.apsusc.2003.12.008 SN - 0169-4332 SN - 1873-5584 VL - 227 SP - 318 EP - 324 PB - North-Holland CY - Amsterdam AN - OPUS4-3479 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Senoner, Mathias A1 - Wirth, Thomas A1 - Unger, Wolfgang T1 - Teststreifen für den Nanokosmos KW - Laterale Auflösung KW - Nanometrologie KW - Nanotechnologie KW - Oberflächenanalytik KW - Zertifiziertes Referenzmaterial PY - 2004 UR - http://www.laborpraxis.de/ SN - 0344-1733 SN - 1610-8256 VL - 27 IS - Juli/Aug SP - 30 EP - 32, Sonderh. Nanotechnologie PB - Vogel CY - Würzburg AN - OPUS4-3808 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kuhmann, J. A1 - Harde, P. A1 - Pech, O. A1 - Pittroff, W. A1 - Preuß, A. A1 - Adolphi, B. A1 - Wirth, Thomas A1 - Österle, Werner ED - Reichl, H. T1 - Fluxless flip-chip bonding for the photonic assembly - comparison between evaporated SnPb (60/40) and AuSn (80/20) solder T2 - 5th International Conference on Micro-Electro-, -Opto-, -Mechanical Systems and Components CY - Potsdam, Germany DA - 1996-09-17 PY - 1996 SN - 3-8007-2200-3 VL - 5 SP - 91 EP - 97 PB - VDE-Verl. CY - Berlin AN - OPUS4-2544 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Senoner, Mathias A1 - Wirth, Thomas A1 - Unger, Wolfgang A1 - Escher, M. A1 - Weber, N. A1 - Funnenmann, D. A1 - Krömker, B. T1 - Testing of Lateral Resolution in the Nanometre Range Using the BAM-L002 - Certified Reference Material: Application to ToF-SIMS IV and NanoESCA Instruments T2 - International Symposium on Practical Surface Analysis CY - Jeju, Republic of Corea DA - 2004-10-04 KW - ESCA KW - Nanometrologie KW - Nanotechnologie KW - Oberflächenanalytik KW - SIMS KW - XPS KW - Zertifiziertes Referenzmaterial PY - 2005 SN - 1341-1756 SN - 1347-8400 VL - 12 IS - 2 SP - 78 EP - 82 CY - Tsukuba AN - OPUS4-11146 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wirth, Thomas T1 - Surface analysis of dental enamel by TOF-SIMS, SEM and TEM T2 - SIMS EUROPE 2006 CY - Münster, Germany DA - 2006-09-24 PY - 2006 AN - OPUS4-13190 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wirth, Thomas T1 - TOF-SIMS investigation of coated glass beads T2 - 18th International Conference on Secondary Ion Mass Spectrometry CY - Riva del Garda, Italy DA - 2011-09-18 PY - 2011 AN - OPUS4-24240 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Moritz, W. A1 - Werner, R. A1 - Tausche, A. A1 - Cherkaschinin, G. A1 - Molajew, R. A1 - Wirth, Thomas A1 - Unger, Wolfgang A1 - Linke, S. T1 - Alloys for gas sensors investigated using the continuous gradient-high throughput screening macroscope CG-HTSM N2 - Ternary alloys have been studied as the gate metal of chemical sensors based on the field effect in silicon. The investigation of reduced poisoning of hydrogen sensors by H2S is presented in the alloy system PdxNiyCo1-x-y. A new method in high throughput screening of alloys is applied. Not singular sample compositions but a continuous gradient in alloy concentrations was produced on a semiconductor sample. A laser scanning system produces a photo current in the semiconductor to map the sensor signal and provide a quasi continuous alloy characterization. The new system is therefore called Continuous Gradient—High Throughput Screening Macroscope (CG-HTSM). Typically 625 alloys are characterized in 15 minutes. The resolution of our set-up allows distinguishing 100.000 alloy compositions. KW - Alloy KW - Sensor KW - High throughput screening KW - Macroscope PY - 2011 DO - https://doi.org/10.1166/sl.2011.1586 SN - 1546-198X SN - 1546-1971 VL - 9 IS - 2 SP - 662 EP - 664 PB - American Scientific Publishers (ASP) CY - Stevenson Ranch, CA, USA AN - OPUS4-24504 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Abou-Ras, D. A1 - Caballero, R. A1 - Fischer, C.-H. A1 - Kaufmann, C.A. A1 - Lauermann, I. A1 - Mainz, R. A1 - Mönig, H. A1 - Schöpke, A. A1 - Stephan, C. A1 - Streeck, C. A1 - Schorr, S. A1 - Eicke, A. A1 - Döbeli, M. A1 - Gade, B. A1 - Hinrichs, J. A1 - Nunney, T. A1 - Dijkstra, H. A1 - Hoffmann, V. A1 - Klemm, D. A1 - Efimova, V. A1 - Bergmaier, A. A1 - Dollinger, G. A1 - Wirth, Thomas A1 - Unger, Wolfgang A1 - Rockett, A.A. A1 - Perez-Rodriguez, A. A1 - Alvarez-Garcia, J. A1 - Izquierdo-Roca, V. A1 - Schmid, T. A1 - Choi, P.-P. A1 - Müller, M. A1 - Bertram, F. A1 - Christen, J. A1 - Khatri, H. A1 - Collins, R.W. A1 - Marsillac, S. A1 - Kötschau, I. T1 - Comprehensive comparison of various techniques for the analysis of elemental distributions in thin films N2 - The present work shows results on elemental distribution analyses in Cu(In,Ga)Se2 thin films for solar cells performed by use of wavelength-dispersive and energy-dispersive X-ray spectrometry (EDX) in a scanning electron microscope, EDX in a transmission electron microscope, X-ray photoelectron, angle-dependent soft X-ray emission, secondary ion-mass (SIMS), time-of-flight SIMS, sputtered neutral mass, glow-discharge optical emission and glow-discharge mass, Auger electron, and Rutherford backscattering spectrometry, by use of scanning Auger electron microscopy, Raman depth profiling, and Raman mapping, as well as by use of elastic recoil detection analysis, grazing-incidence X-ray and electron backscatter diffraction, and grazing-incidence X-ray fluorescence analysis. The Cu(In,Ga)Se2 thin films used for the present comparison were produced during the same identical deposition run and exhibit thicknesses of about 2 µm. The analysis techniques were compared with respect to their spatial and depth resolutions, measuring speeds, availabilities, and detection limits. KW - Elemental distributions KW - Comparison KW - Depth profiling KW - Chemical mapping KW - Thin films KW - Solar cells KW - Chalcopyrite-type KW - Cu(In,Ga)Se2 PY - 2011 DO - https://doi.org/10.1017/S1431927611000523 SN - 1431-9276 SN - 1435-8115 VL - 17 IS - 5 SP - 728 EP - 751 PB - Cambridge University Press CY - New York, NY AN - OPUS4-24506 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Beck, Uwe A1 - Reiners, Georg A1 - Wirth, Thomas A1 - Hoffmann, V. A1 - Präßler, F. T1 - Multilayer reference coatings for depth profile standards N2 - Depth profiles of layer systems consisting of different film materials and having different thicknesses are of great practical importance. Multilayer reference coatings of conducting (Ti/Al) and non-conducting (SiO2/Si3N4) material are analyzed with Auger electron spectroscopy (AES) and glow discharge optical emission spectroscopy (GDOES) depth profiling. Deposition techniques, physical vapor deposition for Ti/Al layers and plasma-enhanced chemical vapor deposition for SiO2/Si3N4 layers, as well as measurement and testing procedures for the determination of layer thickness such as optical and mechanical stylus and spectroscopie ellipsometry are discussed. GDOES depth profiles in direct current (d.c.) and radio frequency (r.f.) mode are related to measurements of crater profiles and compared with line scans and depth profiles performed by AES. It is shown that such multilayer reference systems are appropriate for calibration of depth profiles, i.e. the definition and the evaluation of the depth resolution at the interface, the determination of sputter rates both for d.c.- and r.f.-GDOES and AES, the optimization of the conditions of analysis, and the quantification of analysis itself. KW - Depth profiling KW - Multilayers KW - Glow discharge KW - Auger electron spectroscopy PY - 1996 DO - https://doi.org/10.1016/S0040-6090(96)09083-9 SN - 0040-6090 VL - 290-291 SP - 57 EP - 62 PB - Elsevier CY - Amsterdam AN - OPUS4-25436 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Almagro, J.-F. A1 - Busch, P. A1 - Gohil, D. D. A1 - Heikinheimo, E. A1 - Karduck, P. A1 - Richter, S. A1 - Sloof, W. G. A1 - Thiot, J.-F. A1 - Wirth, Thomas T1 - Electron-Probe MICROanalysis of LighT Elements - Measurement Methods and Certified Reference Materials (MICROLITE) PY - 2002 IS - 65 SP - 1 EP - 156 PB - National Physical Laboratory CY - Teddington, Middlesex AN - OPUS4-1911 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wirth, Thomas A1 - Beck, Uwe A1 - Hoffmann, V. A1 - Kurt, R. A1 - Kämmer, K. A1 - Thielsch, R. T1 - Interference Phenomena at Transparent Layers in Glow Discharge Optical Emission Spectrometry KW - Glow discharge optical emission spectroscopy KW - Depth profile KW - Interference KW - Transparent layers KW - Layer thickness KW - Refractive index KW - GD-OES PY - 1999 SN - 0003-7028 SN - 1943-3530 VL - 53 IS - 8 SP - 987 EP - 990 PB - Society for Applied Spectroscopy CY - Frederick, Md. AN - OPUS4-777 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Beck, Uwe A1 - Wirth, Thomas A1 - Sahre, Mario A1 - Männ, Marion A1 - Gamer, Nadja A1 - Hoffmann, V. A1 - Hentschel, R. A1 - Brauneck, U. A1 - Mollenhauer, R. ED - Berg, S. T1 - Reference coatings for gdoes depth profiling - Preliminary results of a VAMAS project T2 - 7th International Conference on Plasma Surface Engineering (PSE 2000) CY - Garmisch-Partenkirchen, Germany DA - 2000-09-17 PY - 2000 SN - 0257-8972 IS - 142-144 PB - Elsevier CY - Amsterdam AN - OPUS4-970 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, Ralf A1 - Behrens, Harald A1 - Ageo-Blanco, Boris A1 - Reinsch, Stefan A1 - Wirth, Thomas T1 - Foaming Species and Trapping Mechanisms in Barium Silicate Glass Sealants N2 - Barium silicate glass powders 4 h milled in CO2 and Ar and sintered in air are studied with microscopy, total carbon analysis, differential thermal Analysis (DTA), vacuum hot extraction mass spectroscopy (VHE-MS), Fourier-transformed infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and time-of-flight secondary-ion mass spectrometry (TOF-SIMS). Intensive foaming of powder compacts is evident, and VHE studies prove that foaming is predominantly caused by carbonaceous species for both milling gases. DTA Shows that the decomposition of BaCO3 particles mix-milled with glass powders occurs at similar temperatures as foaming of compacts. However, no carbonate at the glass surface could be detected by FTIR spectroscopy, XPS, and TOF-SIMS after heating to the temperature of sintering. Instead, CO2 molecules unable to rotate identified by FTIR spectroscopy after milling, probably trapped by mechanical dissolution into the glass bulk. Such a mechanism or microencapsulation in cracks and particle aggregates can explain the contribution of Ar to foaming after intense milling in Ar atmosphere. The amount of CO2 molecules and Ar, however, cannot fully explain the extent of foaming. Carbonates mechanically dissolved beneath the surface or encapsulated in cracks and micropores of particle aggregates are therefore probably the major foaming source. KW - Milling KW - Foaming KW - Glass powder KW - Sintering PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-531227 DO - https://doi.org/10.1002/adem.202100445 SN - 1438-1656 VL - 24 IS - 6 SP - 2100445-1 EP - 2100445-13 AN - OPUS4-53122 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kirner, Sabrina A1 - Wirth, Thomas A1 - Sturm, Heinz A1 - Krüger, Jörg A1 - Bonse, Jörn T1 - Nanometer-resolved chemical analyses of femtosecond laser-induced periodic surface structures on titanium N2 - The chemical characteristics of two different types of laser-induced periodic surface structures (LIPSS), so-called high and low spatial frequency LIPSS (HSFL and LSFL), formed upon irradiation of titanium surfaces by multiple femtosecond laser pulses in air (30 fs, 790 nm, 1 kHz), are analyzed by various optical and electron beam based surface analytical techniques, including micro-Raman spectroscopy, energy dispersive X-ray analysis, X-ray photoelectron spectroscopy, and Auger electron spectroscopy. The latter method was employed in a high-resolution mode being capable of spatially resolving even the smallest HSFL structures featuring spatial periods below 100 nm. In combination with an ion sputtering technique, depths-resolved chemical information of superficial oxidation processes was obtained, revealing characteristic differences between the two different types of LIPSS. Our results indicate that a few tens of nanometer shallow HSFL are formed on top of a ∼150 nm thick graded superficial oxide layer without sharp interfaces, consisting of amorphous TiO2 and partially crystallized Ti2O3. The larger LSFL structures with periods close to the irradiation wavelength originate from the laser-interaction with metallic titanium. They are covered by a ∼200 nm thick amorphous oxide layer, which consists mainly of TiO2 (at the surface) and other titanium oxide species of lower oxidation states underneath. KW - Laser-induced periodic surface structures (LIPSS) KW - Femtosecond laser KW - Oxidation KW - Titanium KW - Auger electron spectroscopy PY - 2017 DO - https://doi.org/10.1063/1.4993128 SN - 0021-8979 VL - 122 IS - 10 SP - 104901, 1 EP - 9 PB - AIP Publishing CY - Melville, NY, USA AN - OPUS4-41905 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan A1 - Wirth, Thomas A1 - Reiners, Georg ED - Berg, S. T1 - Glow Discharge Optical Emission Spectroscopy (GDOES) - A powerful tool for the characterisation of coatings T2 - 7th International Conference on Plasma Surface Engineering (PSE 2000) CY - Garmisch-Partenkirchen, Germany DA - 2000-09-17 PY - 2000 SN - 0257-8972 IS - 142-144 SP - 1(?) EP - 15(?) PB - Elsevier CY - Amsterdam AN - OPUS4-960 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -