TY - THES A1 - Rackwitz, Vanessa T1 - Instrumentelle Fundamentalparameter und ausgewählte Anwendungen der Mikrofokus-Röntgenfluoreszenzanalyse am Rasterelektronenmikroskop N2 - Seit einem Jahrzehnt sind Röntgenquellen für die Mikrofokus-Röntgenfluoreszenzanalyse (μ-RFA) kommerziell erhältlich und bieten die Möglichkeit, die Analytik am Rasterelektronenmikroskop (REM) mit angeschlossenem energiedispersiven Röntgenspektrometer (EDS) zu erweitern. Mit der μ-RFA lässt sich quantitativ, referenzfrei und zerstörungsfrei der Gehalt der chemischen Elemente in einem mikroskopischen Probenvolumen bestimmen. Für die referenzfreie Quantifizierung mit der RFA wird auf die Sherman-Gleichung zurückgegriffen. Diese Gleichung führt die Intensität der detektierten Röntgenstrahlung auf den Gehalt des Elements in der Probe mittels Fundamentalparameter zurück. Zu den instrumentellen Fundamentalparametern zählen das Anregungsspektrum bestehend aus dem Röntgenröhrenspektrum und der Transmission der Röntgenoptik, die Messgeometrie und die Spektrometereffizienz. Das Ziel dieser Arbeit ist die Entwicklung von Prozeduren zur Charakterisierung der instrumentellen Fundamentalparameter der μ-RFA am REM sowie die Evaluierung und Verringerung der Messunsicherheiten anhand einer kalibrierten Instrumentierung: Die aus der Literatur bekannten Algorithmen zur Berechnung von Röntgenröhrenspektren sollen hinsichtlich ihrer Abweichungen evaluiert werden. Ein semi-empirischer Ansatz wird innerhalb dieser Arbeit bezüglich seiner Unsicherheiten und im niederenergetischen Bereich verbessert. Für drei weitere Anodenmaterialien soll dieser Ansatz erweitert werden. Die mit diesem Ansatz berechneten Röntgenröhrenspektren werden mit direkt gemessenen Röntgenröhrenspektren verglichen, die an einem speziell entwickelten Messstand eines Röntgenröhrenherstellers aufgenommen wurden. Eine Prozedur zur Bestimmung der wichtigsten Parameter von Röntgenhalblinsen im parallelisierenden Modus wird entwickelt. Die zeitliche Stabilität der Transmission von Röntgenvolllinsen, die seit mehreren Jahren im regelmäßigen Einsatz an einer μ-RFA-Quelle waren, wird untersucht. Für das Labor wird ein Verfahren zur Bestimmung der Spektrometereffizienz bis 50 keV neu entwickelt. Neben dieser methodischen Weiterentwicklung werden Anwendungen für die neu charakterisierten instrumentellen Fundamentalparameter vorgestellt. Darunter soll die referenzfreie Quantifizierung mit der μ-RFA am REM anhand von repräsentativen Probenklassen hinsichtlich ihrer Stärken und Schwächen vorgestellt werden. Die Nachweisgrenzen der μ-RFA am REM für schwere Spurenelemente in leichten Matrizen werden an Proben zur Überprüfung einer EU-Richtlinie bestimmt. Darüber hinaus soll überprüft werden, ob die Berücksichtigung der Streueigenschaften einer Probe von Röntgenphotonen für die Analytik ausgenutzt werden kann. N2 - For a decade X-ray sources have been commercially available for the microfocus X-ray fluorescence analysis (μ-XRF) and offer the possibility of extending the analytics at a scanning electron microscope(SEM) with an attached energy dispersive X-ray spectrometer (EDS). By using the μ-XRF it is possible to determine the content of chemical elements in a microscopic sample volume in a quantitative, reference-free and non-destructive way. For the reference-free quantification with the XRF the Sherman equation is referred to. This equation deduces the intensity of the detected X-ray intensity of a fluorescence peak to the content of the element in the sample by means of fundamental parameters. The instrumental fundamental parameters of the μ-XRF at a SEM/EDS system are the excitation spectrum consisting of X-ray tube spectrum and the transmission of the X-ray optics, the geometry and the spectrometer efficiency. Based on a calibrated instrumentation the objectives of this work are the development of procedures for the characterization of all instrumental fundamental parameters as well as the evaluation and reduction of their measurement uncertainties: The algorithms known from the literature for the calculation of X-ray tube spectrum are evaluated with regard to their deviations in the spectral distribution. Within this work a novel semi-empirical model is improved with respect to its uncertainties and enhanced in the low energy range as well as Extended for another three anodes. The emitted X-ray tube spectrum is calculated from the detected one, which is measured at an especially developed setup for the direct measurement of X-ray tube spectra. This emitted X-ray tube spectrum is compared to the one calculated on base of the model of this work. A procedure for the determination of the most important parameters of an X-ray semi-lens in parallelizing mode is developed. The temporal stability of the transmission of X-ray full lenses, which have been in regular use at the μ-XRF source for several years, is examined. The procedure for the determination of the spectrometer efficiency in the laboratory is extended to 50 keV. Besides this methodological development applications for the newly characterized instrumental fundamental Parameters are presented. The reference-free quantification of μ-XRF spectra of representative samples is performed. The limits of detection of the μ-XRF at the SEM are determined for heavy trace elements in light matrices by the example of specimens that were prepared an EU directive. It is investigated if the consideration of the X-ray scattering properties of a sample can extend the XRF analysis. T3 - BAM Dissertationsreihe - 81 KW - Mikrofokus-Röntgenfluoreszenzanalyse KW - Rasterelektronenmikroskop KW - instrumentelle Fundamentalparameter PY - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-771 SN - 978-3-9814634-4-6 SN - 1613-4249 VL - 81 SP - 1 EP - 163 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-77 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Hodoroaba, Vasile-Dan A1 - Procop, M. T1 - Check and specification of the performance of EDX spectrometers attched to the SEM - A new test material and an uptaded software package T2 - 13th European Workshop on modern developments and applications in microbeam analysis (EMAS 2013) CY - Oporto, Portugal DA - 2013-05-12 PY - 2013 AN - OPUS4-28508 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Hodoroaba, Vasile-Dan T1 - An Attempt of Exploiting the Compton-to-Rayleigh Intensity Ratio for Improved Analysis with mu-XRF at a SEM T2 - European Conference on X-Ray Spectrometry EXRS 2012 CY - Vienna, Austria DA - 2012-06-18 PY - 2012 AN - OPUS4-26145 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Ostermann, Markus A1 - Hodoroaba, Vasile-Dan T1 - Limits of detection of mu-XRF with the SEM/EDS for RoHS relevant elements T2 - European Conference on X-Ray Spectrometry EXRS 2012 CY - Vienna, Austria DA - 2012-06-18 PY - 2012 AN - OPUS4-26146 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Ostermann, Markus A1 - Panne, Ulrich A1 - Hodoroaba, Vasile-Dan T1 - Limits of Detection of µ-XRF with SEM/EDS for RoHS relevant elements T2 - PRORA 2011 Fachtagung Prozessnahe Röntgenanalytik CY - Berlin, Germany DA - 2011-11-24 PY - 2011 AN - OPUS4-24792 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Ostermann, Markus A1 - Panne, Ulrich A1 - Hodoroaba, Vasile-Dan T1 - Limits of detection of µ-XRF with the SEM/EDS for RoHS relevant elements T2 - 76. Jahrestagung der DPG und DPG-Frühjahrstagung CY - Berlin, Germany DA - 2012-03-25 PY - 2012 AN - OPUS4-25525 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rackwitz, Vanessa A1 - Panne, Ulrich A1 - Hodoroaba, Vasile-Dan T1 - Calculation of X-ray tube spectra by means of photon generation yields and a modified Kramers background for side-window X-ray tubes N2 - Popular X-ray tube models available in the literature, i.e. 'Pella', 'Ebel', and 'Finkelshtein and Pavlova', are systematically evaluated with the focus on the estimation of the associated uncertainties. Also taken in consideration and compared is our recent semi-empirical own approach already employed in our lab. This has been working for the common target elements rhodium, molybdenum and tungsten and was further extended in the present work for the target elements copper, chromium and vanadium. By using a modern scanning electron microscope/energy dispersive spectroscopy (SEM/EDS) system this time, higher performances such as stability of the beam current and especially the better energy resolution of the EDS have enabled the reliable extension of our own X-ray tube spectrum approach into the low-energy range, due to increasing interest. Hence, also the more challenging X-ray lines of copper, chromium and vanadium L-series lying in the energy range below 1–2?keV are included into the model. Such low-energy L-lines or, e.g. M-lines of tungsten, are not treated explicitly by the other existing popular algorithms for the nowadays widely used geometries of side-window tubes, offering a unique virtue to our present, modern approach. With our own model, a measurement uncertainty of the X-ray tube spectra (considering the uncertainties associated with the SEM beam current, the detector acceptance solid angle and efficiency of the spectrometer) within 15% has been estimated. The validation of the approach is demonstrated with metrological measurements with a calibrated SEM/EDS system geometrically configured as a side-window X-ray tube. KW - X-ray tube spectra KW - Side-window X-ray tube KW - Reference-free XRF KW - Photon generation yield KW - Kramers background KW - Calibrated SEM/EDS PY - 2012 U6 - https://doi.org/10.1002/xrs.2391 SN - 0049-8246 VL - 41 IS - 4 SP - 264 EP - 272 PB - Wiley CY - Chichester AN - OPUS4-26239 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Hodoroaba, Vasile-Dan A1 - Panne, Ulrich T1 - Quantitative referenzfreie Röntgenfluoreszenzanalyse (RFA) - Unsicherheiten bei der Bestimmung der spektralen Röntgenröhrenverteilungen T2 - ANAKON 2009 CY - Berlin, Germany DA - 2009-03-17 PY - 2009 AN - OPUS4-18136 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Hodoroaba, Vasile-Dan A1 - Warrikhoff, A. A1 - Panne, Ulrich T1 - Uncertainties at the Determination of the X-Ray Tube Spectral Distribution T2 - EMAS 2009 CY - Gdansk, Poland DA - 2009-05-10 PY - 2009 AN - OPUS4-18477 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Hodoroaba, Vasile-Dan A1 - Procop, Mathias A1 - Warrikhoff, A. A1 - Panne, Ulrich T1 - The Determination of the Efficiency of an Energy Dispersive X-Ray Spectrometer up to 50keV with a SEM using a calibrated Reference Spectrometer T2 - EMAS 2009 CY - Gdansk, Poland DA - 2009-05-10 PY - 2009 AN - OPUS4-18462 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rackwitz, Vanessa A1 - Ostermann, Markus A1 - Panne, Ulrich A1 - Hodoroaba, Vasile-Dan T1 - Performance of mu-XRF with SEM/EDS for trace analysis on the example of RoHS relevant elements - measurement, optimisation and predivtion of the detection limits N2 - For ten years µ-XRF (micro-focus X-ray fluorescence) analysis has been performed with SEM/EDS (scanning electron microscope with an energy dispersive X-ray detector) so that non-destructive analysis of elements at trace level concentrations below 100 µg g-1 becomes possible. This can be considered as a valuable completion of the classical electron probe microanalysis by EDS, an analytical method 'suffering' from rather poor limits of detection in the range of one to two orders of magnitude higher than those of µ-XRF. Based on a representative actual application, namely analysis of RoHS relevant elements at trace concentration levels, the performance of the rather new analytical method with respect to its limits of detection is systematically evaluated. CRMs (certified reference materials) specially prepared to support the quantitative XRF analysis of RoHS relevant elements were employed. On the other side, based on calculations of µ-XRF spectra according to a recently developed physical model the optimization of the analytical performance is also successfully undertaken. KW - RoHS KW - XRF KW - muXRF KW - SEM/EDS KW - Detection limits KW - Trace elements KW - Modelling PY - 2013 U6 - https://doi.org/10.1039/c3ja50064k SN - 0267-9477 SN - 1364-5544 VL - 28 IS - 9 SP - 1466 EP - 1474 PB - Royal Society of Chemistry CY - London AN - OPUS4-29045 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Hodoroaba, Vasile-Dan A1 - Procop, M. T1 - Check and specification of the performance of EDX spectrometers attched to the SEM - A new test material and an uptaded software package T2 - PRORA 2013 Fachtagung Prozessnahe Röntgenanalytik CY - Berlin, Germany DA - 2013-11-21 PY - 2013 AN - OPUS4-29568 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Krumrey, M. A1 - Scholze, F. A1 - Laubis, C. A1 - Hodoroaba, Vasile-Dan T1 - Neue Referenz- und Testmaterialien sowie Prozeduren zur Funktionskontrolle und Spezifizierung von energie-dispersiven Röntgenspektrometern T2 - PRORA 2013 Fachtagung Prozessnahe Röntgenanalytik CY - Berlin, Germany DA - 2013-11-21 PY - 2013 AN - OPUS4-29569 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Hodoroaba, Vasile-Dan T1 - Kalibrierung eines Messstandes für Röntgenröhren T2 - Forschungsseminar "Moderne analytische Methoden der Physik", TU Berlin CY - Berlin, Germany DA - 2009-02-03 PY - 2009 AN - OPUS4-18730 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rackwitz, Vanessa A1 - Warrikhoff, A. A1 - Panne, Ulrich A1 - Hodoroaba, Vasile-Dan T1 - Determination of the efficiency of an energy dispersive X-ray spectrometer up to 50 keV with a SEM N2 - Both electron and polychromatic photon excitations (micro-focus X-ray source) at a scanning electron microscope (SEM) are used to determine the efficiency of an energy dispersive X-ray spectrometer up to 50 keV by means of a calibrated X-ray spectrometer and reference materials (RM) specially selected for this purpose. KW - Detector efficiency KW - Calibration KW - XRF KW - EDS KW - SEM KW - EDS-TM001 KW - Scattering PY - 2009 U6 - https://doi.org/10.1039/b907815k SN - 0267-9477 SN - 1364-5544 VL - 24 SP - 1034 EP - 1036 PB - Royal Society of Chemistry CY - London AN - OPUS4-19714 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Rackwitz, Vanessa A1 - Reuter, Dirk T1 - X-ray scattering and its benefits for X-ray spectrometry at the SEM PY - 2009 U6 - https://doi.org/10.1017/S1431927609094392 SN - 1431-9276 SN - 1435-8115 VL - 15 IS - Suppl. 2 SP - 1122 EP - 1123 PB - Cambridge University Press CY - New York, NY AN - OPUS4-19792 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Radtke, Martin A1 - Vincze, L. A1 - Rackwitz, Vanessa A1 - Reuter, Dirk T1 - X-ray scattering in X-ray fluorescence spectra with X-ray tube excitation - Modelling, experiment, and Monte-Carlo simulation N2 - X-ray scattering may contribute significantly to the spectral background of X-ray fluorescence (XRF) spectra. Based on metrological measurements carried out with a scanning electron microscope (SEM) having attached a well characterised X-ray source (polychromatic X-ray tube) and a calibrated energy dispersive X-ray spectrometer (EDS) the accuracy of a physical model for X-ray scattering is systematically evaluated for representative samples. The knowledge of the X-ray spectrometer efficiency, but also of the spectrometer response functions makes it possible to define a physical spectral background of XRF spectra. Background subtraction relying on purely mathematical procedures is state-of-the-art. The results produced by the analytical model are at least as reliable as those obtained by Monte-Carlo simulations, even without considering the very challenging contribution of multiple scattering. Special attention has been paid to Compton broadening. Relevant applications of the implementation of the analytical model presented in this paper are the prediction of the limits of detection for particular cases or the determination of the transmission of X-ray polycapillary lenses. KW - X-ray scattering KW - X-ray fluorescence KW - Spectral background KW - Modelling KW - Monte-Carlo simulation PY - 2010 U6 - https://doi.org/10.1016/j.nimb.2010.09.017 SN - 0168-583X SN - 1872-9584 VL - 268 IS - 24 SP - 3568 EP - 3575 PB - Elsevier CY - Amsterdam AN - OPUS4-22357 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rackwitz, Vanessa A1 - Procop, M. A1 - Bjeoumikhova, S. A1 - Panne, Ulrich A1 - Hodoroaba, Vasile-Dan T1 - A routine procedure for the characterisation of polycapillary X-ray semi-lenses in prallelising mode with SEM/EDS N2 - The accurate knowledge of the properties of polycapillary X-ray semi-lenses has a significant influence on the quantitative results in a widespread field of applications involving microfocus X-ray beams. A routine procedure for the characterisation of a polycapillary X-ray semi-lens with a scanning electron microscope (SEM) having attached an energy dispersive spectrometer (EDS) is presented in this paper. A key issue of the procedure consists of fitting the semi-lens in front of the EDS for spectra acquisition. Relevant semi-lens parameters such as focal distance, full width at half maximum (FWHM) of the acceptance area, and transmission are determined in parallelising mode of the semi-lens. Special attention has been paid to the calculation of the transmission. KW - Polycapillary X-ray optics KW - Semi-lens KW - Parallelising mode KW - SEM KW - EDS KW - Acceptance area KW - FWHM KW - Transmission KW - Focal distance KW - XRF PY - 2011 U6 - https://doi.org/10.1039/c0ja00135j SN - 0267-9477 SN - 1364-5544 VL - 26 IS - 3 SP - 499 EP - 504 PB - Royal Society of Chemistry CY - London AN - OPUS4-23555 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Procop, Mathias A1 - Hodoroaba, Vasile-Dan T1 - Characterization of Polycapillary X-Ray Semilenses with SEM/EDX T2 - Microscopy & Microanalysis CY - Portland, OR, USA DA - 2010-08-01 PY - 2010 AN - OPUS4-20907 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Warrikhoff, A. A1 - Panne, Ulrich A1 - Hodoroaba, Vasile-Dan T1 - Determination of Emitted X-Ray Tube Spectra by Means of a Calibrated Instrumental Setup T2 - Microscopy & Microanalysis CY - Portland, OR, USA DA - 2010-08-01 PY - 2010 AN - OPUS4-20915 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Warrikhoff, A. A1 - Panne, Ulrich A1 - Hodoroaba, Vasile-Dan T1 - Determination of emitted X-ray tube spectra by means of a calibrated instrumental setup T2 - EMAS 2010, 9th EMAS Regional Workshop CY - Amsterdam, Netherlands DA - 2010-04-25 PY - 2010 AN - OPUS4-21061 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Salge, T. A1 - Terborg, R. A1 - Rackwitz, Vanessa T1 - Advanced elemental analysis with ED-EPMA, WD-EPMA and mu-XRF at a SEM N2 - It is a latent wish of any SEM/EDS (scanning electron microscope with an energy dispersive spectrometer) analyst to “see more” of the analyzed specimen, i.e. to improve the existing analytical figures of merit. One key issue are the relatively poor limits of detection (not below 0.1 mass-%) provided by energy dispersive X-ray spectrometry (EDX) with the conventional electron excitation (ED-EPMA). This is a consequence of relatively low peak-to-background ratios and reduced energy resolution when compared to wavelength dispersive spectrometry (WD-EPMA). Recent technological developments make possible to equip the SEM with a wavelength dispersive spectrometer (WDS), so that significantly better energy resolution can be attained. Also a relative new product that can be easily attached to a SEM/EDS system is a micro-focus X-ray source. Hence, it is possible to perform (micro-focus) X-ray fluorescence spectrometry (μ-XRF) and take advantage of the enhanced peak-to-background ratios (well suited for trace analysis). However, there are also some disadvantages: an increased measurement time and excitation with a high current in the 10s of nA range are usually required for WDS. μ-XRF provides more bulk information and poor limits of detection for light elements. By combining the advantages of these analytical techniques “seeing more” becomes possible. KW - ED-EPMA KW - WD-EPMA KW - (mu-)XRF KW - EDX PY - 2011 U6 - https://doi.org/10.1017/S1431927611003874 SN - 1431-9276 SN - 1435-8115 VL - 17 IS - Suppl. 2 SP - 600 EP - 601 PB - Cambridge University Press CY - New York, NY AN - OPUS4-26751 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rackwitz, Vanessa A1 - Hodoroaba, Vasile-Dan T1 - An attempt of exploiting the compton-to-rayleigh intensity ratio for improved analysis with muXRF at a SEM KW - X-ray scattering KW - Compton scattering KW - Rayleigh scattering KW - XRF PY - 2012 U6 - https://doi.org/10.1017/S1431927612006678 SN - 1431-9276 SN - 1435-8115 VL - 18 IS - Suppl. 2 SP - 964 EP - 965 PB - Cambridge University Press CY - New York, NY AN - OPUS4-26753 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Rackwitz, Vanessa T1 - Prediction of detection limits of micro X-ray fluorescence (muXRF) KW - X-ray scattering KW - Limits of detection KW - Peak-to-background KW - Peak-to-noise KW - XRF KW - Modelling PY - 2012 U6 - https://doi.org/10.1017/S1431927612006563 SN - 1431-9276 SN - 1435-8115 VL - 18 IS - Suppl. 2 SP - 942 EP - 943 PB - Cambridge University Press CY - New York, NY AN - OPUS4-26754 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rackwitz, Vanessa A1 - Procop, M. A1 - Hodoroaba, Vasile-Dan T1 - Characterization of polycapillary X-ray semilenses with SEM/EDX KW - Polycapillary X-ray optics KW - Semi-lens KW - Parallelising mode KW - SEM KW - EDS KW - Acceptance area KW - FWHM KW - Transmission KW - Focal distance KW - XRF PY - 2010 U6 - https://doi.org/10.1017/S1431927610054280 SN - 1431-9276 SN - 1435-8115 VL - 16 IS - Suppl 2 SP - 932 EP - 933 PB - Cambridge University Press CY - New York, NY AN - OPUS4-27219 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Rackwitz, Vanessa A1 - Reuter, Dirk T1 - Micro-focus X-ray fluorescence (mu-XRF) as an extension of the analytical SEM KW - mu-XRF KW - SEM KW - EDS PY - 2010 U6 - https://doi.org/10.1017/S1431927610054115 SN - 1431-9276 SN - 1435-8115 VL - 16 IS - Suppl. 2 SP - 904 EP - 905 PB - Cambridge University Press CY - New York, NY AN - OPUS4-27220 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Hodoroaba, Vasile-Dan T1 - Röntgenspektroskopie am REM: Von der methodischen Erweiterung zur Metrologie T2 - Institut für Chemische Technologien und Analytik, Technische Universität Wien, Seminar "Moderne Analytische Chemie" CY - Vienna, Austria DA - 2014-01-10 PY - 2014 AN - OPUS4-29958 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rackwitz, Vanessa A1 - Warrikhoff, A. A1 - Hodoroaba, Vasile-Dan T1 - Accurate determination of small spot X-ray tube spectra by means of direct measurement in a calibrated instrumental setup N2 - A calibrated instrumental setup was specially developed for the purposes of accurate measurements of absolute X-ray spectra emitted by modern micro-focus, low-power X-ray tubes. By knowing all the instrumental parameters the spectra measured with the 16 m long setup are recalculated into emitted X-ray tube spectra in photons per eV per msr per nA per s. KW - X-ray tube KW - Calibration KW - Absolute X-ray spectrum KW - Setup PY - 2014 U6 - https://doi.org/10.1039/c3ja50353d SN - 0267-9477 SN - 1364-5544 VL - 29 IS - 3 SP - 458 EP - 463 PB - Royal Society of Chemistry CY - London AN - OPUS4-30196 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Procop, M. A1 - Rackwitz, Vanessa T1 - Check and specification of the performance of EDS systems attached to the SEM by means of a new test material EDS-TM002 and an updated evaluation software package EDS spectrometer test - Version 3.4. N2 - Four years ago BAM has made available via its webshop a test material, EDS-TM001, as well as an accompanying software package, "EDX spectrometer check", to be employed by both EDS (energy dispersive spectrometer) users and manufacturers to check and pecify, respectively, the performance of an EDS. KW - EDS detector KW - EDX KW - Test material KW - EDS-TM002 KW - EDS performance test KW - Software PY - 2013 U6 - https://doi.org/10.1017/S1431927613008271 SN - 1431-9276 SN - 1435-8115 VL - 19 IS - Suppl. 2 SP - 1256 EP - 1257 PB - Cambridge University Press CY - New York, NY AN - OPUS4-29421 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Marinenko, R.B. A1 - Rackwitz, Vanessa A1 - Bremser, Wolfram A1 - Unger, Wolfgang T1 - Determination of the k-values of copper-gold alloys with ED- and WD-EPMA - Results of an inter-laboratory comparison N2 - An inter-laboratory comparison organized as a pilot study (PS) has been performed under the umbrella of the Consultative Committee for Amount of Substance – Metrology in Chemistry (CCQM) / Surface Analysis Working Group (SAWG) with the objective to compare k-values measured with Electron Probe X-ray Microanalysis (EPMA) for copper-gold alloys. The k-value, defined as the ratio of the Xray photon intensity of an X-ray characteristic line of the unknown sample to the corresponding one in the reference material, is a rough estimate of the mass fraction of the respective element. Basically, the mass fractions can be calculated from the k-values after applying a matrix correction procedure, which includes empirical approaches, so that traceability gets lost. Due to its physical, measurable nature, the k-value has been selected in the present PS as the primary measurand. The mass fraction has been set as the secondary (derived) measurand. Both EDX and WDX have been employed. The WDX results and the overall comparability between the k-values obtained by EDX and WDX are still in progress. KW - Interlaboratory comparison KW - EDX KW - WDX KW - EPMA KW - K-values KW - Cu-Au alloy KW - CCQM PY - 2014 U6 - https://doi.org/10.1017/S1431927614005376 SN - 1431-9276 SN - 1435-8115 VL - 20 IS - Suppl. S 3 SP - 730 EP - 731 PB - Cambridge University Press CY - New York, NY AN - OPUS4-31338 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Hodoroaba, Vasile-Dan T1 - Neue Referenz- und Testmaterialien sowie Prozeduren zur Funktionskontrolle und Spezifizierung von energiedispersiven Röntgenspektrometern (EDS) T2 - Training Course on quality Assure for traceable energy dispersive eletron probe microanalysis (ED-EPMA) CY - Berlin, Germany DA - 2014-03-28 PY - 2014 AN - OPUS4-30587 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Hodoroaba, Vasile-Dan A1 - Benemann, Sigrid T1 - Spezifische Standard ArbeitsAnweisung (StAA) für die Kalibrierung und Funktionskontrolle von energiedispersiven Rötgenspektrometern (EDS) T2 - Training Course on quality Assureance for traceable energy dispersive electron probe microanalysis (ED-EPMA) CY - Berlin, Germany DA - 2014-03-28 PY - 2014 AN - OPUS4-30588 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Hodoroaba, Vasile-Dan A1 - Procop, Mathias T1 - Mikro-Röntgenfluorenszenz-Analyse (µ-RFA) am Rasterelektronen-Mikroskop (REM) T2 - 15. Tagung Festkörperanalytik CY - Chemnitz, Germany DA - 2009-07-12 PY - 2009 AN - OPUS4-19529 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Hodoroaba, Vasile-Dan A1 - Procop, Mathias T1 - Characterisation of Polycapillary Lenses with a Scanning Electron Microscope (SEM) T2 - ICXOM20, 20th International Congress on X-ray Optics and Microanalysis CY - Karlsruhe, Germany DA - 2009-09-14 PY - 2009 AN - OPUS4-19533 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Hodoroaba, Vasile-Dan A1 - Panne, Ulrich T1 - Micro-Focus X-Ray Fluorescence (µ-XRF) Analysis with a Scanning Electron Microscope (SEM) T2 - Euroanalysis 2009 CY - Innsbruck, Austria DA - 2009-09-06 PY - 2009 AN - OPUS4-19536 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Hodoroaba, Vasile-Dan A1 - Warrikhoff, A. A1 - Panne, Ulrich T1 - Experimental Determination of the X-Ray Tube Spectral Distribution with a Scanning Electron Microscope (SEM) T2 - ICXOM20, 20th International Congress on X-ray Optics and Microanalysis CY - Karlsruhe, Germany DA - 2009-09-14 PY - 2009 AN - OPUS4-19537 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Hodoroaba, Vasile-Dan A1 - Procop, Mathias T1 - Mikro-Fokus-Röntgenfluoreszenzanalyse (µ-RFA) am REM T2 - Thermo-Anwendertreffen Mikroanalyse CY - Düsseldorf, Germany DA - 2009-04-21 PY - 2009 AN - OPUS4-19256 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Warrikhoff, A. A1 - Panne, Ulrich A1 - Hodoroaba, Vasile-Dan T1 - Zertifizierung von Röntgenröhrenspektren an einem kalibrierten Messstand T2 - PRORA 2009 CY - Berlin, Germany DA - 2009-11-26 PY - 2009 AN - OPUS4-20086 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Warrikhoff, A. A1 - Panne, Ulrich A1 - Hodoroaba, Vasile-Dan T1 - Determination of emitted X-ray tube spectra by means of a calibrated instrumental setup T2 - EXRS 2010 (European conference on X-Ray Spectrometry CY - Figueira da Foz, Portugal DA - 2010-06-20 PY - 2010 AN - OPUS4-21135 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Procop, M. A1 - Hodoroaba, Vasile-Dan T1 - Characterisation of Polycapillary X-Ray Semi-lenses with SEM/EDX T2 - European Conference on X-Ray Spectrometry, EXRS 2010 CY - Figueira da Foz, Portugal DA - 2010-06-20 PY - 2010 AN - OPUS4-21102 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rackwitz, Vanessa A1 - Warrikhoff, A. A1 - Panne, Ulrich A1 - Hodoroaba, Vasile-Dan T1 - Determination of emitted X-ray tube spectra by means of a calibrated instrumental setup KW - X-ray tube spectrum KW - XRF KW - SEM KW - EDS KW - Spectrometer efficiency PY - 2010 U6 - https://doi.org/10.1017/S1431927610054292 SN - 1431-9276 SN - 1435-8115 VL - 16 IS - Supplement S2 SP - 930 EP - 931 PB - Cambridge University Press CY - New York, NY AN - OPUS4-22471 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Ostermann, Markus A1 - Panne, Ulrich A1 - Hodoroaba, Vasile-Dan T1 - Limits of Detection of µ-XRF with SEM for RoHS relevant Elements T2 - European Microbeam Analysis Society EMAS 2011 CY - Angers, France DA - 2011-05-15 PY - 2011 AN - OPUS4-22503 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Panne, Ulrich A1 - Hodoroaba, Vasile-Dan T1 - An Attempt of µ-XRF Analysis by Exploiting the Rayleigh-to-Compton Intensity Ratio T2 - European Microbeam Analysis Society EMAS 2011 CY - Angers, France DA - 2011-05-15 PY - 2011 AN - OPUS4-22504 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa A1 - Hodoroaba, Vasile-Dan A1 - Procop, Mathias T1 - Mikro-Röntgenfluoreszenz-Analyse (µ-RFA) am Rasterelektronen-Mikroskop (REM) T2 - 15. Tagung Festkörperanalytik CY - Chemnitz, Germany DA - 2009-07-12 PY - 2009 AN - OPUS4-19466 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rackwitz, Vanessa T1 - Evaluierung von IMOXS-Quant unter Verwendung von Referentmaterialien T2 - Nutzertreffen iMOXS, BAM CY - Berlin, Germany DA - 2009-10-01 PY - 2009 AN - OPUS4-20043 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Procop, Mathias A1 - Hodoroaba, Vasile-Dan A1 - Rackwitz, Vanessa T1 - A microfocus X-ray source for improved EDS and XRF analysis in the SEM N2 - A microfocus X-ray source mounted on the analysis chamber of an SEM was used to excite X-ray fluorescence spectra and to detect chemical elements with concentrations below the detection limit of the electron-excited X-ray spectra conventionally measured with SEM/EDS. An aluminium alloy and a hard material ceramics were analysed as representative examples. It is demonstrated that the combination of the three analytical methods: (1) SEM imaging for surface morphology characterisation; (2) electron-excited X-ray spectroscopy with its high spatial resolution for element analysis of inclusions or precipitates; and (3) X-ray fluorescence for the detection of elements with concentrations below 0.1 mass% considerably improves the performance of SEM/EDX analyses. KW - Scanning electron microscopy KW - Microanalysis KW - Energy-dispersive X-ray spectroscopy KW - X-ray fluorescence KW - Micro-XRF KW - Materials science PY - 2011 SN - 2043-0655 VL - 25 IS - 4 SP - 11 EP - 13 PB - Wiley CY - Chichester AN - OPUS4-23764 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rackwitz, Vanessa A1 - Krumrey, M. A1 - Laubis, C. A1 - Scholze, F. A1 - Hodoroaba, Vasile-Dan T1 - New reference and test materials for the characterization of energy dispersive X-ray spectrometers at scanning electron microscopes N2 - Checking the performance of energy dispersive X-ray spectrometers as well as validation of the results obtained with energy dispersive X-ray spectrometry (EDX) at a scanning electron microscope (SEM) involve the use of (certified) reference and dedicated test materials. This paper gives an overview on the test materials mostly employed by SEM/EDX users and accredited laboratories as well as on those recommended in international standards. The new BAM reference material EDS-CRM, which is currently in the process of certification, is specifically designed for the characterization of EDS systems at a SEM through calibration of the spectrometer efficiency in analytical laboratories in a simple manner. The certification of the spectra by means of a reference EDS is described. The focus is on the traceability of EDS efficiency which is ensured by measurements of the absolute detection efficiency of silicon drift detectors (SDD) and Si(Li) detectors at the laboratory of the PTB using the electron storage ring BESSY II as a primary X-ray source standard. A new test material in development at BAM for testing the performance of an EDS in the energy range below 1 keV is also briefly presented. KW - EDX KW - EDS KW - Performance check KW - SEM KW - Test materials KW - Spectrometer efficiency PY - 2015 U6 - https://doi.org/10.1007/s00216-014-8242-5 SN - 1618-2642 SN - 1618-2650 VL - 407 IS - 11 SP - 3045 EP - 3053 PB - Springer CY - Berlin AN - OPUS4-33025 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Rackwitz, Vanessa T1 - Gaining improved chemical composition by exploitation of compton-to-rayleigh intensity ratio in XRF analysis N2 - The high specificity of the coherent (Rayleigh), as well as incoherent (Compton) X-ray scattering to the mean atomic number of a specimen to be analyzed by X-ray fluorescence (XRF), is exploited to gain more information on the chemical composition. Concretely, the evaluation of the Compton-to-Rayleigh intensity ratio from XRF spectra and its relation to the average atomic number of reference materials via a calibration curve can reveal valuable information on the elemental composition complementary to that obtained from the reference-free XRF analysis. Particularly for matrices of lower mean atomic numbers, the sensitivity of the approach is so high that it can be easily distinguished between specimens of mean atomic numbers differing from each other by 0.1. Hence, the content of light elements which are “invisible” for XRF, particularly hydrogen, or of heavier impurities/additives in light materials can be calculated 'by difference' from the scattering calibration curve. The excellent agreement between such an experimental, empirical calibration curve and a synthetically generated one, on the basis of a reliable physical model for the X-ray scattering, is also demonstrated. Thus, the feasibility of the approach for given experimental conditions and particular analytical questions can be tested prior to experiments with reference materials. For the present work a microfocus X-ray source attached on an SEM/EDX (scanning electron microscopy/energy dispersive X-ray spectroscopy) system was used so that the Compton-to-Rayleigh intensity ratio could be acquired with EDX spectral data for improved analysis of the elemental composition. PY - 2014 U6 - https://doi.org/10.1021/ac5000619 SN - 0003-2700 SN - 1520-6882 VL - 86 IS - 14 SP - 6858 EP - 6864 PB - American Chemical Society CY - Washington, DC AN - OPUS4-31179 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -