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 JF - Microscopy and microanalysis PY - 2009 DO - 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 JF - Nuclear instruments and methods in physics research B 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 DO - 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 - 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 JF - Microscopy and microanalysis 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 DO - 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 JF - Microscopy and microanalysis KW - X-ray scattering KW - Compton scattering KW - Rayleigh scattering KW - XRF PY - 2012 DO - 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) JF - Microscopy and microanalysis KW - X-ray scattering KW - Limits of detection KW - Peak-to-background KW - Peak-to-noise KW - XRF KW - Modelling PY - 2012 DO - 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 JF - Microscopy and microanalysis 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 DO - 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 JF - Microscopy and microanalysis KW - mu-XRF KW - SEM KW - EDS PY - 2010 DO - 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 - 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 JF - Journal of analytical atomic spectrometry 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 DO - 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. JF - Microscopy and microanalysis 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 DO - 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 JF - Microscopy and microanalysis 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 DO - 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 -