Hostname: page-component-78c5997874-fbnjt Total loading time: 0 Render date: 2024-11-18T06:04:33.623Z Has data issue: false hasContentIssue false

Quantitative Measurement of Iron-Silicides by EPMA Using the Fe Lα and Lβ X-ray Lines: A New Twist to an Old Approach

Published online by Cambridge University Press:  12 April 2019

Aurélien Moy*
Affiliation:
Department of Geoscience, University of Wisconsin, Madison, WI 53706, USA
John Fournelle
Affiliation:
Department of Geoscience, University of Wisconsin, Madison, WI 53706, USA
Anette von der Handt
Affiliation:
Department of Earth Sciences, University of Minnesota, Minneapolis, MN 55455, USA
*
*Author for correspondence: Aurélien Moy, E-mail: amoy6@wisc.edu
Get access

Abstract

The recent availability of Schottky-type field emission electron microprobes provides incentive to consider analyzing micrometer-sized features. Yet, to quantify sub-micrometer-sized features, the electron interaction volume must be reduced by decreasing accelerating voltage. However, the K lines of the transition elements (e.g., Fe) then cannot be excited, and the L lines must be used. The Fe Lα1,2 line is the most intense of the L series but bonding effects change its atomic parameters because it involves a valence band electron transition. For successful traditional electron probe microanalysis, the mass absorption coefficient (MAC) must be accurately known, but the MAC of Fe Lα1,2 radiation by Fe atoms varies from one Fe-compound to another and is not well known. We show that the conventional method of measuring the MAC by an electron probe cannot be used in close proximity to absorption edges, making its accurate determination impossible. Fortunately, we demonstrate, using a set of Fe–silicide compounds, that it is possible to derive an accurate calibration curve, for a given accelerating voltage and takeoff angle, which can be used to quantify Fe in Fe–silicide compounds. The calibration curve can be applied to any spectrometer without calibration and gives accurate quantification results.

Type
Materials Applications
Copyright
Copyright © Microscopy Society of America 2019 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Armstrong, JT (1988). Bence-Albee after 20 years: Review of the accuracy of α-factor correction procedures for oxide and silicate minerals. In Microbeam Analysis, Newbury, DE (Ed.), pp. 469476. San Francisco: San Francisco Press.Google Scholar
Bence, AE & Albee, AL (1968). Empirical correction factors for the electron microanalysis of silicates and oxides. J Geol 76(4), 382403.10.1086/627339Google Scholar
Buse, B & Kearns, S (2018). Quantification of olivine using Fe Lα in electron probe microanalysis (EPMA). Microsc Microanal 24, 17.Google Scholar
Castaing, R (1951). Application des sondes électronique à une méthode d'analyse ponctuelle chimique et cristallographique. PhD Thesis. University of Paris, France. Publication ONERA No. 55.Google Scholar
Chantler, CT, Olsen, K, Dragoset, RA, Chang, J, Kishore, AR, Kotochigova, SA & Zucker, DS (2005). X-ray form factor, attenuation and scattering tables (version 2.1). National Institute of Standards and Technology, Gaithersburg, MD. Available at http://physics.nist.gov/ffast (retrieved August 15, 2018).Google Scholar
Chen, CT, Idzerda, YU, Lin, H-J, Smith, NV, Meigs, G, Chaban, E, Ho, GH, Pellegrin, E & Sette, F (1995). Experimental confirmation of the X-ray magnetic circular dichroism sum rules for iron and cobalt. Phys Rev Lett 75, 152155.Google Scholar
Cullen, DE, Hubbell, JH & Kissel, L (1997). EPDL97 The Evaluated Data Library, Technical Report UCRL-50400. Livermore, CA: Lawrence Livermore National Laboratory.Google Scholar
Donovan, J, Kremser, D, Fournelle, J & Goemann, K (2018). Probe for Windows User's Guide and Reference, Enterprise edition. Eugene, OR: Probe Software, Inc.Google Scholar
Elam, WT, Ravel, BD & Sieber, JR (2002). A new atomic database for X-ray spectroscopic calculations. Radiat Phys Chem 63(2), 121128.Google Scholar
Essene, EJ & Fisher, DC (1986). Lightning strike fusion: Extreme reduction and metal-silicate liquid immiscibility. Science 234, 189193.Google Scholar
Fournier, C, Merlet, C, Dugne, O & Fialin, M (1999). Standardless semi-quantitative analysis with WDS-EPMA. J Anal At Spectrom 14, 381386.10.1039/a807433jGoogle Scholar
Goldstein, JI, Newbury, DE, Michael, JR, Ritchie, NWM, Scott, JHJ & Joy, DC (2018). Electron beam—specimen interactions: Interaction volume. In Scanning Electron Microscopy and X-Ray Microanalysis, 4th ed. pp. 114, New York, NY: Springer.Google Scholar
Gopon, P, Fournelle, J, Sobol, PE & Llovet, X (2013). Low-voltage electron-probe microanalysis of Fe–Si compounds using soft X-rays. Microsc Microanal 19, 16981708.Google Scholar
Heinrich, KFJ (1987). Mass absorption coefficients for electron probe microanalysis. In Proceedings of the 11th International Congress on X-ray Optics and Microanalysis, Brown, JD & Packwood, RH (Eds.), pp. 67119. London, Ontario: University of Western Ontario Press.Google Scholar
Ida, T, Ando, M & Toraya, H (2000). Extended pseudo-Voigt function for approximating the Voigt profile. J Appl Cryst 33, 13111316.Google Scholar
Lee, JC, Xiang, J, Ravel, B, Kortright, J & Flanagan, K (2009). Condensed matter astrophysics: A prescription for determining the species-specific composition and quantity of interstellar dust using X-rays. Astrophys J 702, 970979.Google Scholar
Llovet, X, Pinard, PT, Heikinheimo, E, Louhenkilpi, S & Richter, S (2016). Electron probe microanalysis of Ni silicides using Ni-L X-ray lines. Microsc Microanal 22, 12331243.Google Scholar
McSwiggen, P (2014). Characterisation of sub-micrometre features with the FE-EPMA. IOP Conf Ser Mater Sci Eng 55, 012009.Google Scholar
Perepezko, JH & Hebert, RJ (2002). Amorphous aluminum alloys—synthesis and stability. JOM 54(3), 3439.Google Scholar
Pinard, PT (2016). Electron probe microanalysis of carbon containing steels at a high spatial resolution. PhD Thesis. RWTH Aachen University, Germany.Google Scholar
Pouchou, JL (1996). Use of soft X-rays in microanalysis. Mikrochim Acta 13(Suppl), 3960.Google Scholar
Pouchou, JL & Pichoir, F (1988). Determination of mass absorption coefficients for soft X-rays by use of the electron microprobe. In Microbeam Analysis, Newbury, DE (Ed.), pp. 319324. San Francisco: San Francisco Press.Google Scholar
Pouchou, JL & Pichoir, F (1991). Quantitative analysis of homogeneous or stratified microvolumes applying the model “PAP”. In Electron Probe Quantitation, Heirinch, KFJ & Newbury, DE (Eds.), pp. 223249. New York: Plenum Press.Google Scholar
Rémond, G, Myklebust, R, Fialin, M, Nockolds, C, Phillips, M & Roques-Carmes, C (2002). Decomposition of wavelength dispersive X-ray spectra. J Res Natl Inst Stand Technol 107, 509529.Google Scholar
Rietmeijer, FJ, Nakamura, T, Tsuchiyama, A, Uesugi, K, Nakano, T & Leroux, H (2008). Origin and formation of iron silicide phases in the aerogel of the Stardust mission. Meteorit Planet Sci 43(1–2), 121134.Google Scholar
Salvat, F (2015). PENELOPE-2014: A Code System for Monte Carlo Simulation of Electron and Photon Transport. Issy-les-Moulineaux, France: OECD/Nuclear Energy Agency. Available at http://www.nea.fr/lists/penelope.html.Google Scholar
Scott, VD, Love, G & Reed, SJB (1995). Quantitative Electron-Probe Microanalysis. 2nd ed. New York: Ellis Horwood.Google Scholar
Shiryaev, AA, Griffin, WL & Stoyanov, E (2011). Moissanite (SiC) from kimberlites: Polytypes, trace elements, inclusions and speculations on origin. Lithos 122, 152164.Google Scholar
Sokaras, D, Kochur, AG, Müller, M, Kolbe, M, Beckhoff, B, Mantler, M, Zarkadas, C & Andrianis, M (2011). Cascade L-shell soft-X-ray emission as incident X-ray photons are tuned across the 1s ionization threshold. Phys Rev A 83, 052511.Google Scholar
STRATAGem Version 2.6, SAMx, 4, rue Galilée, 78280 Guyancourt, France.Google Scholar
Ziebold, TO & Ogilvie, RE (1963). Quantitative analysis with the electron microanalyzer. Anal Chem 35(6), 621627.Google Scholar