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 U6 - 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 - 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 - CONF A1 - Terborg, R. A1 - Hodoroaba, Vasile-Dan A1 - Kim, K. J. T1 - Determination of Thin Film Thickness and Composition using Energy Dispersive EPMA N2 - Electron Probe Microanalysis (EPMA) provides a non-destructive approach in the dedicated thin film analysis mode with the commercial StrataGem software. Recently, the open-source programme BadgerFilm by Moy and Fournelle became available. Similarly to StrataGem, it is based on the algorithm of Pouchou and Pichoir and needs intensity ratios of the unknown sample and standards (k-values). We have evaluated the k-values measured for the FeNi and SiGe film systems using the BadgerFilm software package and compared the thickness and composition with the results obtained with the established StrataGem software and other reference methods. The thicknesses of the SiGe films obtained by the BadgerFilm software agree within 20% with the StrataGem and TEM results; the elemental compositions BadgerFilm-StrataGEM agree within 2% with one exception (9%). T2 - Microscopy and Microanalysis 2022 CY - Portland, OR, USA DA - 31.07.2022 KW - Thin films KW - Thickness KW - Elemental composition KW - FeNi KW - SiGe KW - BadgerFilm KW - Electron Probe Microanalysis (EPMA) PY - 2022 AN - OPUS4-55522 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Terborg, R. A1 - Kim, K. J. A1 - Hodoroaba, Vasile-Dan T1 - Determination of Thin Film Thickness and Composition using Energy Dispersive EPMA N2 - The thickness of thin films can be measured by various methods, e.g., profilometry, ellipsometry, atomic force microscopy (AFM), or X-ray reflectometry. For the additional determination of thin film composition, techniques like X-ray photoelectron spectroscopy (XPS) or mass spectrometry-based techniques can be used. An alternative non-destructive technique is electron probe microanalysis (EPMA). This method assumes a sample of homogenous (bulk) chemical composition, so that it cannot be usually applied to thin film samples. However, in combination with the thin film software StrataGEM, the thickness as well as the composition of such films on a substrate can be determined. This has been demonstrated for FeNi on Si and SiGe on Al2O3 film systems. For both systems five samples with different elemental composition and a reference were produced and characterised by Korean research institute KRISS using inductively coupled plasma mass spectrometry (ICP-MS), Rutherford backscattering (RBS), and transmission electron microscopy (TEM). These samples were used for an international round robin test. In 2021, a new and open-source thin film evaluation programme called BadgerFilm has been released. It can also be used to determine thin film composition and thickness from intensity ratios of the unknown sample and standards (k-ratios). In this contribution, we re-evaluated the data acquired for the FeNi and SiGe systems using the BadgerFilm software package and compared the resulting composition and thickness with the results of the established StrataGEM software and other reference methods. With the current evaluation, the BadgerFilm software shows good agreement with the composition and thickness calculated by StrataGEM and as the reference values provided by the KRISS. KW - Thin films KW - Elemental composition KW - Film thickness KW - EPMA (Electron Probe Microanalysis) PY - 2022 U6 - https://doi.org/10.1017/S143192762200318X VL - 28 IS - Suppl. 1 SP - 672 EP - 673 PB - Cambridge University Press AN - OPUS4-55437 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Terborg, R. A1 - Hodoroaba, Vasile-Dan A1 - Falke, M. A1 - Käppel, A. T1 - On the characterization of the geometrical collection efficiency of modern EDS systems N2 - To compare the performance of different energy dispersive X-ray spectrometers (EDS), it is important to define characteristic spectrometer parameters. The ISO 15632 standard defines parameters like energy resolution as FWHM for the Kα lines of carbon, fluorine and manganese. The quantum efficiency, which is the ratio of the detected photons divided by the number of incoming photons for different energies, is another significant spectrometer property. It is important for the light element and low energy line detection sensitivity as well as for higher photon energies above 10 keV. A striking EDS feature, provided and marketed by many manufactures, is the active area of the detector, although actually, the solid angle available for photon collection is the more relevant geometrical parameter. It is defined as: Ω = A /r2 with A being the active area of a spherical detector and r being the distance between the point of the radiation origin and the center of the surface of the active detector chip. A more accurate calculation should be used for large flat detector areas. One should note that the solid angle Ω is not an intrinsic spectrometer property. It can only be defined for a specific detector in combination with a specific system (e.g. SEM, EPMA or TEM). Thus, the minimal possible distance r is determined by the particular geometry e.g. a possible interference with the pole piece or other detectors/components in the chamber of a microscope. New EDS technologies use e.g. integrated SDD chips or inclined chips in thinner detector fingers which can be placed closer to the sample with the final result of larger real solid angles. Therefore, the knowledge of the real solid angle is one of the crucial parameters of an EDS microscope combination. A straightforward way to estimate the real solid angle is to simply determine A and r. If respective data are not provided by the manufacturer, this approach can be difficult. KW - EDS KW - EDX KW - Geometrical collection efficiency KW - Solid angle PY - 2014 U6 - https://doi.org/10.1017/S1431927614007454 SN - 1431-9276 SN - 1435-8115 VL - 20 IS - Suppl. S 3 SP - 1144 EP - 1145 PB - Cambridge University Press CY - New York, NY AN - OPUS4-31388 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Wirth, Thomas A1 - Terborg, R. A1 - Kim, K.J. A1 - Unger, Wolfgang T1 - Measurement of atomic fractions in Cu(In,Ga)Se2 films by Auger Electron Spectroscopy (AES) and Energy Dispersive Electron Probe Microanalysis (ED-EPMA) N2 - A pilot study (PS) has been performed under the Consultative Committee for Amount of Substance (CCQM) / Surface Analysis Working Group (SAWG) with the objective to compare the atomic fractions of Cu, In, Ga and Se in CIGS alloy films. Four polycrystalline CIGS films with different atomic fractions were fabricated by variation of the relative atomic fraction of Ga on 100 mm x 100 mm soda-lime glass (SLG) substrates. Similar to real solar cells the atomic fractions of the four elements (Cu, In, Ga, Se) are not homogeneous with depth. For the analysis of the CIGS layers of about 2 μm thickness depth profiling with surface analysis techniques such as XPS, AES and SIMS was recommended. A CIGS alloy reference sample with atomic fractions certified by isotope dilution ICP-MS at KRISS has been also put at disposal by the coordinator of the comparison. The certified values were close to the atomic fractions of the samples to be analyzed. Hence, the atomic fractions of Cu, In, Ga and Se in the CIGS films could be determined by the relative sensitivity factors (RSF) derived from the reference CIGS film. The total ion intensities of the constituent elements were obtained by the total number counting (TNC) method. KW - Interlaboratory comparison KW - Auger Electron Spectroscopy (AES) KW - EDX KW - EPMA KW - CIGS KW - CCQM PY - 2014 U6 - https://doi.org/10.1017/S1431927614003730 SN - 1431-9276 SN - 1435-8115 VL - 20 IS - Suppl. S 3 SP - 402 EP - 403 PB - Cambridge University Press CY - New York, NY AN - OPUS4-31339 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Salge, T. A1 - Terborg, R. A1 - Ball, A. D. A1 - Broad, G.R. A1 - Kearsley, A.T. A1 - Jones, C.G. A1 - Smith, C. A1 - Rades, Steffi A1 - Hodoroaba, Vasile-Dan ED - Hozak, P. T1 - Advanced SEM/EDS analysis using an annular silicon drift detector (SDD): Applications in nano, life, earth and planetary sciences below micrometer scale T2 - IMC 2014 - 18th International microscopy congress CY - Prague, Czech Republic DA - 2014-09-07 PY - 2014 SN - 978-80-260-6720-7 SP - IT-5-P-1842, 1-2 AN - OPUS4-31944 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Terborg, R. A1 - Hodoroaba, Vasile-Dan A1 - Falke, M. A1 - Käppel, A. ED - Hozak, P. T1 - Characterization of EDS systems with respect to the geometrical collection efficiency T2 - IMC 2014 - 18th International microscopy congress CY - Prague, Czech Republic DA - 07.09.2014 KW - EDS KW - EDX KW - Geometrical collection efficiency KW - Solid angle PY - 2014 SN - 978-80-260-6720-7 SP - IT-5-P-1533, 1-2 AN - OPUS4-31945 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Terborg, R. A1 - Procop, M. T1 - Determination of the effective EDS detector area using experimental and theoretical X-ray emission yields N2 - An energy dispersive X-ray spectrometer operating with a semiconductor detector should be specified in compliance with the ISO standard 15632 [1]. Requirements for specification are: a) a general description of the spectrometer to evaluate its performance, b) the energy resolution with corresponding dead time, c) the P/B ratio in the Fe55 spectrum and, finally, d) the L/K intensity Ratio in a Ni or Cu spectrum to estimate spectrometer efficiency at low energies. Items b) to d) can be easily checked by the user. Related procedures are recommended in the annexes of the standard. KW - EDS KW - X-rays KW - Effective solid angle PY - 2015 U6 - https://doi.org/10.1017/S1431927615008181 SN - 1431-9276 SN - 1435-8115 VL - 21 IS - Suppl. 3 SP - Paper 0739, 1481 EP - 1482 PB - Cambridge University Press CY - New York, NY AN - OPUS4-34342 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 U6 - 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 -