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Electron-Excited X-Ray Microanalysis at Low Beam Energy: Almost Always an Adventure!†

Published online by Cambridge University Press:  12 August 2016

Dale E. Newbury  and
Nicholas W.M. Ritchie
Dale E. Newbury*
Affiliation:
Materials Science Measurement Division, National Institutes of Standards and Technology, Gaithersburg, MD 20899, USA
Nicholas W.M. Ritchie
Affiliation:
Materials Science Measurement Division, National Institutes of Standards and Technology, Gaithersburg, MD 20899, USA
*
*Corresponding author.[email protected]
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Abstract

Scanning electron microscopy with energy-dispersive spectrometry has been applied to the analysis of various materials at low-incident beam energies, E0≤5 keV, using peak fitting and following the measured standards/matrix corrections protocol embedded in the National Institute of Standards and Technology Desktop Spectrum Analyzer-II analytical software engine. Low beam energy analysis provides improved spatial resolution laterally and in-depth. The lower beam energy restricts the atomic shells that can be ionized, reducing the number of X-ray peak families available to the analyst. At E0=5 keV, all elements of the periodic table except H and He can be measured. As the beam energy is reduced below 5 keV, elements become inaccessible due to lack of excitation of useful characteristic X-ray peaks. The shallow sampling depth of low beam energy microanalysis makes the technique more sensitive to surface compositional modification due to formation of oxides and other reaction layers. Accurate and precise analysis is possible with the use of appropriate standards and by accumulating high count spectra of unknowns and standards (>1 million counts integrated from 0.1 keV to E0).

Keywords

DTSA-IIEDSmicroanalysisSEMX-ray
Type
Technique and Instrumentation Development
Information
Microscopy and Microanalysis , Volume 22 , Issue 4 , August 2016 , pp. 735 - 753
Copyright
© Microscopy Society of America 2016 

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Footnotes

†

Certain commercial equipment, instruments, or materials are identified in this paper to foster understanding. Such identification does not imply recommendation or endorsement by the National Institute of Standards and Technology, nor does it imply that the materials or equipment identified are necessarily the best available for the purpose.

References

Castaing, R. (1951). Application of electron probes to metallographic analysis. Paris: PhD dissertation, University of Paris.Google Scholar
Chantler, C.T., Olsen, K., Dragoset, R.A., Chang, J., Kishore, A.R., Kotochigova, S.A. & Zucker, D.S. (2000). X-ray form factor, attenuation and scattering tables, version 2.1. Phys Chem Ref Data 29(4), 597–1048.Google Scholar
Goldstein, J., Newbury, D., Joy, D., Lyman, C., Echlin, P., Lifshin, E., Sawyer, L. & Michael, J. (2003). Scanning Electron Microscopy and X-Ray Microanalysis, 3rd ed. New York, NY: Springer.Google Scholar
Kanaya, K. & Okayama, S. (1972). Penetration and energy-loss theory of electrons in solid targets. J Phys D Appl Phys 5(1), 43–58.Google Scholar
Newbury, D.E. & Ritchie, N.W.M. (2015 a). Review: performing elemental microanalysis with high accuracy and high precision by scanning electron microscopy/silicon drift detector energy dispersive X-ray spectrometry (SEM/SDD-EDS). J. Mater Sci 50, 493–518.Google Scholar
Newbury, D.E. & Ritchie, N.W.M. (2015 b). Quantitative electron-excited X-ray microanalysis of borides, carbides, nitrides, oxides, and fluorides with scanning electron microscopy/silicon drift detector energy-dispersive spectrometry (SEM/SDD-EDS) and NIST DTSA-II. Microsc Microanal 21, 1327–1340.Google Scholar
Pouchou, J.-L. & Pichoir, F. (1991). ‘Quantitative analysis of homogeneous or stratified microvolumes applying the model ‘PAP’. In Electron Probe Quantitation, Heinrich K.F.J. & Newbury D.E. (Eds.). pp 31–75. New York, NY: Plenum.CrossRefGoogle Scholar
Ritchie, N.W.M. (2015). NIST DTSA-II software, including tutorials. Available at www.cstl.nist.gov/div837/837.02/epq/dtsa2/index.html (retrieved May 6, 2016).Google Scholar
Ritchie, N.W.M. & Newbury, D.E. (2012). Uncertainty estimates for electron probe X-ray microanalysis measurements. Anal Chem 84, 9956–9962.Google Scholar
Ritchie, N.W.M., Newbury, D.E. & Davis, J.M. (2012). EDS measurements at WDS precision and accuracy using a silicon drift detector. Microsc Microanal 18, 892–904.Google Scholar
Struder, L., Fiorini, C., Gatti, E., Hartmann, R., Holl, P., Krause, N., Lechner, P., Longoni, A., Lutz, G., Kemmer, J., Meidinger, N., Popp, M., Soltau, H. & von Zanthier, C. (1998). Mikrochim Acta 15(Suppl), 11–19.Google Scholar