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Electron Probe Microanalysis Through Coated Oxidized Surfaces

Published online by Cambridge University Press:  16 July 2019

Mike B. Matthews*
Affiliation:
AWE, Aldermaston, Reading, RG7 4PR, UK University of Bristol, School of Earth Sciences, Wills Memorial Building, Queens Road, Clifton, BS8 1RJ, UK
Ben Buse
Affiliation:
University of Bristol, School of Earth Sciences, Wills Memorial Building, Queens Road, Clifton, BS8 1RJ, UK
Stuart L. Kearns
Affiliation:
University of Bristol, School of Earth Sciences, Wills Memorial Building, Queens Road, Clifton, BS8 1RJ, UK
*
*Author for correspondence: Mike B. Matthews, E-mail: matthm@hotmail.com
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Abstract

Low voltage electron probe microanalysis (EPMA) of metals can be complicated by the presence of a surface oxide. If a conductive coating is applied, analysis becomes one of a three-layer structure. A method is presented which allows for the coating and oxide thicknesses and the substrate intensities to be determined. By restricting the range of coating and oxide thicknesses, tc and to respectively, x-ray intensities can be parameterized using a combination of linear functions of tc and to. tc can be determined from the coating element k-ratio independently of the oxide thickness. to can then be derived from the O k-ratio and tc. From tc and to the intensity components of the k-ratios from the oxide layer and substrate can each be derived. Modeled results are presented for an Ag on Bi2O3 on Bi system, with tc and to each ranging from 5 to 20 nm, for voltages of 5–20 kV. The method is tested against experimental measurements of Ag- or C-coated samples of polished Bi samples which have been allowed to naturally oxidize. Oxide thicknesses determined both before and after coating with Ag or C are consistent. Predicted Bi Mα k-ratios also show good agreement with EPMA-measured values.

Type
Materials Applications
Copyright
Copyright © Microscopy Society of America 2019 

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References

Anderson, CA (1966). Electron probe microanalysis of thin layers and small particles with emphasis on light element determinations. In The Electron Microprobe, McKinley, TD, Heinrich, KFJ & Wittry, DB (Eds.), pp. 5874. New York: John Wiley and Sons, Inc.Google Scholar
Buse, B, Kearns, SL, Clapham, C & Hawley, D (2016). Decontamination in the electron probe microanalysis with a Peltier-cooled cold finger. Microsc Microanal 22(5), 981986. 10.1017/S1431927616011715.Google Scholar
Hou, PY & Stringer, J (1995). The effect of reactive element additions on the selective oxidation, growth and adhesion of chromia scales. Mater Sci Eng A 202(1–2), 110. doi: 10.1016/0921-5093(95)09798-8.Google Scholar
Hutchins, GA (1966). Thickness determination of thin films by electron probe microanalysis. In The Electron Microprobe, McKinley, TD, Heinrich, KFJ & Wittry, DB (Eds.), pp. 390404. New York: John Wiley and Sons, Inc.Google Scholar
Jurek, K, Renner, O & Krouský, E (1994). The role of coating densities in X-ray microanalysis. Mikrochim Acta 114–115(1), 323326. doi: 10.1007/BF01244558.Google Scholar
Kerrick, DM, Eminhizer, LB & Villaume, JF (1973). The role of carbon film thickness in electron microprobe analysis. Am Mineral 58, 920925.Google Scholar
Limandri, SP, Carreras, AC & Trincavelli, JC (2010). Effects of the carbon coating and the surface oxide layer in electron probe microanalysis. Microsc Microanal 16(05), 583593. doi: 10.1017/S1431927610093761.Google Scholar
Liou, HK, Mei, P, Gennser, U & Yang, ES (1991). Effects of Ge concentration on SiGe oxidation behavior. Appl Phys Lett 59(10), 12001202. 10.1063/1.105502.Google Scholar
Llovet, X & Salvat, F (2016). PENEPMA: A Monte Carlo programme for the simulation of X-ray emission in EPMA. IOP Conf Ser: Mater Sci Eng 109, 012009. doi: 10.1088/1757-899X/109/1/012009.Google Scholar
Marshall, DJ & Hall, TA (1968). Electron-probe X-ray microanalysis of thin films. J Phys D: Appl Phys 1(12), 310. doi: 10.1088/0022-3727/1/12/310.Google Scholar
Matthews, MB, Kearns, SL & Buse, B (2018a). Electron beam-induced carbon erosion and the impact on electron probe microanalysis. Microsc Microanal 24(6), 612622. doi: 10.1017/S143192761801539.Google Scholar
Matthews, MB, Kearns, SL & Buse, B (2018b). The accuracy of Al and Cu film thickness determinations and the implications for electron probe microanalysis. Microsc Microanal 24(2), 8392. doi: 10.1017/S1431927618000193.Google Scholar
Meier, GH, Jung, K, Mu, N, Yanar, NM, Pettit, FS, Pirón Abellán, J, Olszewski, T, Nieto Hierro, L, Quadakkers, WJ & Holcomb, GR (2010). Effect of alloy composition and exposure conditions on the selective oxidation behavior of ferritic Fe-Cr and Fe-Cr-X alloys. Oxid Met 74(5–6), 319340. 10.1007/s11085-010-9215-5.Google Scholar
Pouchou, J-L (1993). X-Ray microanalysis of stratified specimens. Analytica Chimica Acta 283, 8197.Google Scholar
Pouchou, J-L & Pichoir, F (1990). Surface film X-ray microanalysis. Scanning 12(4), 212224.Google Scholar
Salvat, F (2015). PENELOPE-2014. A Code System for Monte Carlo Simulation of Electron and Photon Transport’. Issy-les-Moulineaux, France: OECD/NEA Data Bank. Available at http://www.oecd-nea.org/lists/penelope.html.Google Scholar
Smith, MP (1986). Silver coating inhibits electron microprobe beam damage of carbonates. J Sediment Petrol 56(4), 560561.Google Scholar
Wagner, C (1952). Theoretical analysis of the diffusion processes determining the oxidation rate of alloys. J Electrochem Soc 99(10), 369. doi: 10.1149/1.2779605Google Scholar
Waldo, RA (1988). An iteration procedure to calculate film compositions and thicknesses in electron-probe microanalysis. In Microbeam Analysis, Newbury, DE (Ed.), pp. 310314. San Francisco: San Francisco Press.Google Scholar
Whittle, DP & Stringer, J (1980). Improvements in high temperature oxidation resistance by additions of reactive elements or oxide dispersions. Philosophical Transactions of the Royal Society of London A 295, 309329.Google Scholar
Willich, P (1992). EPMA – a versatile technique for the characterisation of thin films and layered structures. In Electron Microbeam Analysis: Mikrochimica Acta Supplement, Boekestein, A & Pavicevic, MK (Eds.), pp. 117. Vienna: Springer.Google Scholar
Willich, P & Schiffmann, K (1992). EPMA of surface oxide films. In Electron Microbeam Analysis: Mikrochimica Acta Supplement, Boekestein, A & Pavicevic, MK (Eds.), pp. 221227. Vienna: Springer.Google Scholar