TY - JOUR A1 - Procop, Mathias A1 - Hodoroaba, Vasile-Dan A1 - Griepentrog, Michael T1 - A new material for the performance check of X-ray spectrometers attached to a SEM T2 - Microscopy and Microanalysis 2006 CY - Chicago, IL, USA DA - 2006-07-30 KW - X-ray spectrometer KW - EDS KW - WDS KW - Calibration PY - 2006 DO - https://doi.org/10.1017/S1431927606061307 SN - 1431-9276 SN - 1435-8115 VL - 12 IS - Supplement 2 SP - 870 EP - 871 PB - Cambridge University Press CY - New York, NY AN - OPUS4-12665 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Procop, Mathias A1 - Hodoroaba, Vasile-Dan A1 - Bjeoumikhov, A. T1 - Calculation of X-ray spectra for a side window tube T2 - Microscopy and Microanalysis CY - Chicago, IL, United States of America DA - 2006-07-30 KW - X-ray spectroscopy KW - X-ray tube KW - Microanalysis KW - XRF PY - 2006 DO - https://doi.org/10.1017/S143192760606123X SN - 1431-9276 SN - 1435-8115 VL - 12 IS - Supplement 2 PB - Cambridge University Press CY - New York, NY AN - OPUS4-12667 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Procop, Mathias A1 - Hodoroaba, Vasile-Dan T1 - X-ray fluorescence as an additional analytical method for a scanning electron microscope N2 - Energy dispersive and wavelength dispersive X-ray spectrometry are used to determine the composition of a specimen in a scanning electron microscope (SEM) by electron probe microanalysis (EPMA). A valuable completion for the SEM is analysis by X-ray fluorescence (XRFA). The main advantage of this method consists in its low detection limit. XRFA with a SEM uses the same spectrometers as for EPMA, necessary are only an additional X-ray source for the excitation of fluorescence spectra and software for their evaluation. Recent developments of smart low-power X-ray tubes and X-ray optical components enabled the construction of compact X-ray sources with focussing properties as add-on for a SEM. For quantitative XRFA the source spectrum has to be known. For its calculation the X-ray production yields Y have been measured for the commonly used tube target materials Mo, Rh and W. The excitation spectra were calculated for a variety of source types and compared with respect to the achievable photon flux and its spectral distribution. KW - X-ray spectroscopy KW - X-ray production yield KW - X-ray tube spectrum KW - X-ray fluorescence analysis KW - XRF KW - X-ray optics KW - Scanning electron microscopy KW - Analytical SEM PY - 2008 DO - https://doi.org/10.1007/s00604-007-0854-4 SN - 0026-3672 SN - 1436-5073 VL - 161 IS - 3-4 SP - 413 EP - 419 PB - Springer CY - Wien AN - OPUS4-17537 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Procop, Mathias T1 - Determination of the real transmission jof an x-ray lens for micro-focus XRF at the SEM by coupling measurement with calculation of scatter spectra KW - X-ray optics KW - Transmission KW - Micro-focus-XRF KW - SEM PY - 2009 DO - https://doi.org/10.1002/xrs.1151 SN - 0049-8246 VL - 38 IS - 3 SP - 216 EP - 221 PB - Wiley CY - Chichester AN - OPUS4-19352 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Procop, Mathias A1 - Hodoroaba, Vasile-Dan T1 - A test material and a quick procedure for the performance check of X-ray spectrometers attached to the SEM PY - 2009 DO - https://doi.org/10.1017/S143192760909432X SN - 1431-9276 SN - 1435-8115 VL - 15 IS - Suppl. 2 SP - 1120 EP - 1121 PB - Cambridge University Press CY - New York, NY AN - OPUS4-19793 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Procop, Mathias T1 - Performance check of a wavelength dispersive X-ray spectrometer (WDS) attached to the SEM PY - 2009 DO - https://doi.org/10.1017/S1431927609094112 SN - 1431-9276 SN - 1435-8115 VL - 15 IS - Suppl. 2 SP - 1118 EP - 1119 PB - Cambridge University Press CY - New York, NY AN - OPUS4-19791 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Terborg, R. A1 - Procop, Mathias T1 - Check of the performance of EDS systems attached to the SEM with the test material EDS-TM001/2 and evaluation software package EDS spectrometer test - Application, experiences and updates N2 - The test material EDS-TM001 together with an accompanying software package, “EDX spectrometer check”, have been made available in 2009 by BAM to be employed by EDS (energy dispersive spectrometer) users to check the performance of an EDS attached to the SEM. Particularly for test laboratories operating under accreditation schemes like ISO/IEC 17025, a periodical control of the critical instrumental parameters in end-user laboratories is required. With EDS-TM001 or EDS-TM002 (second generation) test material, this periodical check is simplified to the acquisition of only one 10 kV spectrum. The software “EDX spectrometer check” is destined to evaluate automatically this spectrum and determine the performance of the EDS in terms of energy resolution and calibration as well as possible alteration of low-energy efficiency due to detector contamination. Energy resolution can be compared with the specified values according to the international ISO standard ISO 15632:2012. EDS-TM is a synthetic material consisting of a thick layer of C, Al, Mn, Cu and Zr in a well-defined composition, deposited on a steel (in case of EDS-TM001) or silicon (in case of EDS-TM002) substrate. Meanwhile, more than one hundred laboratories use the EDS-TM001 or EDS-TM002 test material for the periodical check of their EDS. A detailed description of the test material and software together with examples of application was published recently. New results and gained experiences will be presented as well. When the FWHM of lines appearing in the EDS-TM spectrum are determined, the spectrum background must be subtracted accurately. The applied physical background subtraction procedure is robust and takes into account the transmission of the detector window. While the previous version considers only Moxtek AP windows, the new version includes selection of silicon nitride window and the case of windowless detector. Moreover, the new version allows importing of spectra in Bruker spx format and EMSA/MSA files from EDAX TEAM software. KW - EDS KW - Performance check KW - SEM KW - Test material KW - X-ray spectrometer PY - 2018 UR - https://www.cambridge.org/core/journals/microscopy-and-microanalysis/article/check-of-the-performance-of-eds-systems-attached-to-the-sem-with-the-test-material-edstm0012-and-evaluation-software-package-eds-spectrometer-test-application-experiences-and-updates/3D01FDC765C3ECD734CB8DEC7081DAE2 DO - https://doi.org/10.1017/S1431927618004142 SN - 1431-9276 SN - 1435-8115 VL - 24 IS - S1 (August) SP - 730 EP - 731 PB - Cambridge University Press CY - New York, NY, U.S.A. AN - OPUS4-46006 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Procop, Mathias A1 - Hodoroaba, Vasile-Dan A1 - Terborg, R. A1 - Berger, D. T1 - Determination of the Effective Detector Area of an Energy-Dispersive X-Ray Spectrometer at the Scanning Electron Microscope Using Experimental and Theoretical X-Ray Emission Yields N2 - A method is proposed to determine the effective detector area for energy-dispersive X-ray spectrometers (EDS). Nowadays, detectors are available for a wide range of nominal areas ranging from 10 up to 150mm2. However, it remains in most cases unknown whether this nominal area coincides with the “net active sensor area” that should be given according to the related standard ISO 15632, or with any other area of the detector device. Moreover, the specific geometry of EDS installation may further reduce a given detector area. The proposed method can be applied to most scanning electron microscope/EDS configurations. The basic idea consists in a comparison of the measured count rate with the count rate resulting from known X-ray yields of copper, titanium, or silicon. The method was successfully tested on three detectors with known effective area and applied further to seven spectrometers from different manufacturers. In most cases the method gave an effective area smaller than the area given in the detector description. KW - Energy-dispersive X-ray spectrometer (EDS) KW - EDX KW - Effective area KW - X-ray emission yield KW - Geometrical collection efficiency PY - 2016 UR - https://www.cambridge.org/core/journals/microscopy-and-microanalysis/article/div-classtitledetermination-of-the-effective-detector-area-of-an-energy-dispersive-x-ray-spectrometer-at-the-scanning-electron-microscope-using-experimental-and-theoretical-x-ray-emission-yieldsdiv/E15B2E67C349201CF323E778EB9C6D94 DO - https://doi.org/10.1017/S1431927616011788 VL - 22 IS - 6 SP - 1360 EP - 1368 PB - Cambridge University Press CY - New York, NY, USA AN - OPUS4-38858 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan A1 - Procop, Mathias T1 - Check of Energy-Dispersive X-ray Spectrometers (EDS) Performance with the BAM Test Material EDSTM001/2 and BAM Software EDS Spectrometer Test N2 - The test material EDS-TM001 together with an accompanying software package, “EDX spectrometer check”, have been made available in 2009 by BAM to be employed by EDS (energy-dispersive X-ray spectrometer) users to check the performance of an EDS attached to the SEM. Particularly for test laboratories operating under accreditation schemes like ISO/IEC 17025, a periodical control of the critical instrumental parameters in end-user laboratories is required. With EDS-TM001 or EDS-TM002 (second generation) test material, this periodical check is simplified to the acquisition of only one 10 kV spectrum. The software “EDX spectrometer check” is destined to evaluate automatically this spectrum and determine the performance of the EDS in terms of energy resolution and calibration, as well as possible alteration of low-energy Efficiency due to detector contamination. Energy resolution can be compared with the specified values according to the international ISO standard ISO 15632:2012. EDS-TM is a synthetic material consisting of a 6 μm thick layer of C, Al, Mn, Cu and Zr deposited on a steel (in case of EDS-TM001) or silicon (in case of EDS-TM002) substrate. The chemical composition of EDS-TM was chosen such as to give nearly equal intensities of the low energy lines in a 10 kV spectrum, thus, making it very sensitive against spectrometer efficiency changes. Meanwhile, about 150 laboratories use the EDS-TM001 or EDS-TM002 test material for the periodical check of their EDS. A detailed description of the test material and software together with examples of application was published recently. New results and gained experiences will be presented as well. When the FWHM of the X-ray lines in the EDS-TM spectrum are determined, the spectrum background must be subtracted accurately. The applied physical background subtraction procedure is robust and takes into account the transmission of the detector window. While the previous version considers only Moxtek AP windows, the new version includes selection of silicon Nitride window and the case of windowless detector. Moreover, the new version allows importing of spectra in Bruker spx-format and EMSA/MSA files from EDAX TEAM software. Windowless detectors have been also tested demonstrating long-term stability after repeated heating and cooling cycles. In this case, the appropriate Background subtraction is decisive for accurate detector characterization. Detailed results will be presented. T2 - EMAS 2019 - 16th European Workshop on MODERN DEVELOPMENTS AND APPLICATIONS IN MICROBEAM ANALYSIS CY - Trondheim, Norway DA - 19.05.2019 KW - EDS KW - Test material KW - Software KW - Spectrometer check KW - X-ray spectroscopy PY - 2019 AN - OPUS4-48103 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Procop, Mathias A1 - Hodoroaba, Vasile-Dan A1 - Bjeoumikhov, A. A1 - Eggert, F. A1 - Wedell, R. T1 - Combination of electron probe microanalysis and X-ray fluorescence analysis in a scanning electron microscope T2 - 45th Annual Port Elizabeth Conference CY - Port Elizabeth, South Africa DA - 2006-11-29 KW - myXRF at SEM KW - EPMA KW - Detection limits PY - 2006 SN - 0-620-37294-X VL - 36 SP - 26 CY - Onderstepoort AN - OPUS4-14567 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bjeoumikhov, A. A1 - Arkadiev, V. A1 - Eggert, F. A1 - Hodoroaba, Vasile-Dan A1 - Langhoff, N. A1 - Procop, Mathias A1 - Rabe, J. A1 - Wedell, R. T1 - A new microfocus x-ray source, iMOXS, for highly sensitive XRF analysis in scanning electron microscopes N2 - Scanning electron microscopes are usually equipped with energy-dispersive X-ray detectors for electron probe microanalysis. This widespread analytical method allows investigators to determine the elemental composition of specimens with a spatial resolution of about 1 µm. However, owing to the electron-specimen interaction, the emitted spectra reveal, in addition to characteristic lines, also a high level of continuous bremsstrahlung background. As a result, elements with low concentrations cannot be identified. The minimum detection limit can be diminished by two orders of magnitude if the characteristic lines are excited as fluorescence by an additional x-ray source. In this case, the emergence of bremsstrahlung is considerably reduced. Combining a high-brilliance microfocus x-ray tube with efficient polycapillary optics enables one to realize an experimental arrangement for performing local fluorescence analysis at the same point where the electron beam hits the sample. The polycapillary optics under consideration focuses the emitted x-radiation onto focal spots between 30 and 100 µm in diameter. Count rates of several thousands cps have been achieved. Elemental maps have been obtained by means of the motorized specimen stage of the microscope. Copyright © 2005 John Wiley & Sons, Ltd. KW - Micro-XRF KW - Microfocus x-ray source KW - EPMA KW - SEM PY - 2005 DO - https://doi.org/10.1002/xrs.872 SN - 0049-8246 VL - 34 IS - 6 SP - 493 EP - 497 PB - Wiley CY - Chichester AN - OPUS4-11228 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Alvisi, M. A1 - Blome, M. A1 - Griepentrog, Michael A1 - Hodoroaba, Vasile-Dan A1 - Karduck, P. A1 - Mostert, M. A1 - Nacucchi, M. A1 - Procop, Mathias A1 - Rohde, M. A1 - Scholze, F. A1 - Statham, P. A1 - Terborg, R. A1 - Thiot, J.-F. T1 - The Determination of the Efficiency of Energy Dispersive X-Ray Spectrometers by a New Reference Material N2 - A calibration procedure for the detection efficiency of energy dispersive X-ray spectrometers (EDS) used in combination with scanning electron microscopy (SEM) for standardless electron probe microanalysis (EPMA) is presented. The procedure is based on the comparison of X-ray spectra from a reference material (RM) measured with the EDS to be calibrated and a reference EDS. The RM is certified by the line intensities in the X-ray spectrum recorded with a reference EDS and by its composition. The calibration of the reference EDS is performed using synchrotron radiation at the radiometry laboratory of the Physikalisch-Technische Bundesanstalt. Measurement of RM spectra and comparison of the specified line intensities enables a rapid efficiency calibration on most SEMs. The article reports on studies to prepare such a RM and on EDS calibration and proposes a methodology that could be implemented in current spectrometer software to enable the calibration with a minimum of operator assistance. KW - Energy dispersive X-ray spectrometry KW - Standardless analysis KW - X-ray detectors KW - Detection efficiency KW - Spectrometer calibration PY - 2006 DO - https://doi.org/10.1017/S1431927606060557 SN - 1431-9276 SN - 1435-8115 VL - 12 IS - 5 SP - 406 EP - 415 PB - Cambridge University Press CY - New York, NY AN - OPUS4-13135 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Procop, Mathias A1 - Hodoroaba, Vasile-Dan T1 - Uncertainties in secondary fluorescence correction in EPMA N2 - Secondary fluorescence is an inevitable effect that has to be taken into account in any algorithm for quantitative electron probe microanalysis (EPMA) as an additional correction. Moreover, secondary fluorescence worsens spatial resolution of EPMA. Secondary fluorescence is excited both by characteristic radiation and by the X-ray continuum. In most cases the correction is small. There are, however, cases, e.g. the determination of low heavy metal concentration in a light matrix, where the contribution of secondary fluorescence exceeds 10% of the measured X-ray line intensity. For secondary fluorescence correction the measured X-ray line intensity has to be divided by the correction factor (1+I_flchar/I_p +I_flcont/I_p )≈(1+I_flchar/I_p )(1+I_flcont/I_p ) in order to get those intensity I_p, which is excited only by the primary electrons. I_flchar and I_flcont mean the calculated characteristic and continuums fluorescence intensities. In order to get the intensity of fluorescence radiation, the absorption of the exciting radiation in the specimen, the photoionization probability and the self-absorption of the emitted line must be calculated. The critical quantity is the X-ray yield of the exciting atoms in case of fluorescence by characteristic radiation and the bremsstrahlung yield of the specimen in case of continuum fluorescence. In the former case it is reasonable to apply the same physical model to calculate I_flchar and I_p. KW - EPMA KW - Secondary fluorescence correction KW - Uncertainties KW - Microanalysis PY - 2019 UR - https://www.cambridge.org/core/journals/microscopy-and-microanalysis/article/uncertainties-in-secondary-fluorescence-correction-in-epma/AA92E973D350A74C574067AAFB2D9044 DO - https://doi.org/10.1017/S1431927619012534 SN - 1431-9276 SN - 1435-8115 VL - 25 IS - Suppl. 2 SP - 2360 EP - 2361 PB - Cambridge University Press AN - OPUS4-48863 LA - eng 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 - Procop, Mathias A1 - Hodoroaba, Vasile-Dan A1 - Bjeoumikhov, A. A1 - Wedell, R. A1 - Warrikhoff, A. T1 - Improvements of the low-energy performance of a micro-focus x-ray source for XRF analysis with the SEM N2 - X-ray Fluorescence (XRF) with a scanning electron microscope (SEM) is a valuable completion of the analytical capabilities of SEMs. Small and compact micro-focus x-ray sources are mounted to the microscope chamber, and the x-ray spectra are monitored with conventional EDS systems. Up to now the x-ray tubes used for the micro-focus x-ray sources are equipped with beryllium windows about 100 µm thick. The poly-capillary x-ray lenses have their transmission maximum at photon energies around 10 keV. It drops down in both low- and high-energy ranges. Hence, L-radiation from an Mo or Rh target will be strongly attenuated, and the excitation of fluorescence in the soft x-ray range becomes very ineffective. A new micro-focus x-ray source was developed. It is characterised by a lower self-absorption in the tube target, thin beryllium windows and an x-ray optics having a large distance between its foci and the maximum of transmission at about 5 keV. Thus K line fluorescence of light elements becomes effectively excited by the L-radiation from Mo or Rh tube targets. The detection limit for sodium oxide in glass was found to be below 1 mass%. KW - Micro-focus-XRF KW - X-ray tube KW - X-ray optics KW - SEM PY - 2009 DO - https://doi.org/10.1002/xrs.1159 SN - 0049-8246 VL - 38 IS - 4 SP - 308 EP - 311 PB - Wiley CY - Chichester AN - OPUS4-19583 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -