X-ray Spectra and Images


TheX-ray spectrumgenerated within your specimen consists of element-specific characteristic peaks with well-defined energies superimposed on a non-characteristic background. While the XEDS system is a remarkable piece of technology, we’ve already described its limited resolution and we will see in this chapter that it is also prone to creating small artifact peaks in the spectrum. Furthermore, the unavoidable presence of scattered electrons and X-rays within the AEM conspire to degrade the quality of the generated spectrum and increase the number of false peaks in the displayed spectrum. The AEM illumination system and specimen stage are rich sources of powerful radiation, not all of it by any means coming from the area of interest in your specimen. So you have to take precautions to ensure that the X-ray spectrum you collect comes predominantly from the area of the specimen that you want to analyze and we describe several tests you should perform to ensure that the XEDSTEM interface is optimized.


Thin Foil Data Cube Spectrum Image Escape Peak Standard File Format 


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General References

  1. Garrett-Reed, AJ and Bell, DC 2003 Energy-dispersive X-ray Analysis in the Electron Microscope Bios (Royal Microsc. Soc.) Oxford UK. Different descriptions of many of the issues discussed in this chapter.Google Scholar
  2. Lyman, CE (Ed.) 2006 Microscopy and Microanalysis 12 1. A commemorative edition celebrating 50 years of X-ray mapping; great history and examples of good practice.Google Scholar
  3. Williams, DB, Goldstein, JI and Newbury, DE (Eds.) 1995 X-Ray Spectrometry in Electron Beam Instruments Plenum Press New York. Still the best available source of background information on XEDS hardware and software, even though increasingly dated in content.Google Scholar

Specific References

  1. Allard, LF and Blake, DF 1982 The Practice of Modifying an Analytical Electron Microscope to Produce Clean X-ray Spectra in Microbeam Analysis-1982 8–20 Ed. KFJ Heinrich San Francisco Press San Francisco CA. Early review of system artifacts.Google Scholar
  2. Bright, DS and Newbury, DE 1991 Concentration Histogram Imaging Analytical Chemistry 63 243A–250A. Processing maps for appearance and more.Google Scholar
  3. Cliff, G and Kenway, PB 1982 The Effects of Spherical Aberration in Probe-forming Lenses on Probe Size and Image Resolution in Microbeam Analysis-1982 107–110 Ed. KFJ Heinrich San Francisco Press San Francisco CA. The tail on the probe.Google Scholar
  4. Cosslett, VE and Duncumb, P 1956 Microanalysis by a Flying-spot X-ray Method Nature 177 1172–1173. First dot maps by XEDS—more than 50 years ago!!Google Scholar
  5. Egerton, RF, Fiori, CE, Hunt, JA, Isaacson, MS, Kirkland EJ and Zaluzec, NJ 1991 EMSA/MAS Standard File Format for Spectral Data Exchange EMSA Bulletin 21 35–41. The EMSA/MAS standard file format.Google Scholar
  6. Fiori, CE, Swyt, CR and Ellis, JR 1982 The Theoretical Characteristic to Continuum Ratio in Energy Dispersive Analysis in the Analytical Electron Microscope in Microbeam Analysis-1982, 57–71 Ed. KFJ Heinrich San Francisco Press San Francisco CA. The Fiori P/B definition.Google Scholar
  7. Fiori CE and Swyt, CR 1994 Desk Top Spectrum Analyzer (DTSA), U.S. Patent 5 299 138. The original description of the essential software.Google Scholar
  8. Friel JJ and Lyman CE 2006 Tutorial Review: X-ray Mapping in Electron-Beam Instruments Microscopy and Microanalysis 12 2–25. A good place to start before you map.Google Scholar
  9. Hunneyball, P D, Jacobs, MH and Law, TJ 1981 Digital X-ray Mapping from Thin Foils in Quantitative Microanalysis with High Spatial Resolution 195–202 Eds. GW Lorimer, MH Jacobs and P Doig, The Metals Society London. First digital XEDS maps.Google Scholar
  10. Legge, GJF and Hammond, I 1979 Total Quantitative Recording of Elemental Maps and Spectra with a Scanning Microprobe J. Microsc. 117 201–210. A little history.Google Scholar
  11. Lyman, CE and Ackland, DW 1991 The Standard Hole Count Test: a Progress Report in Microbeam Analysis-1991, 720–721 Ed. DG Howitt San Francisco Press San Francisco CA. Measuring hole count.Google Scholar
  12. Lyman, C.E, Goldstein, JI, Williams, DB, Ackland, DW, von Harrach, S, Nicholls, AW and Statham, P.J 1994 High Performance X-ray Detection in a New Analytical Electron Microscope J. Microsc. 176 85–98. Modifying the stage to use only low-Z materials.Google Scholar
  13. Mott RB and Friel, JJ 1999 Saving the Photons: Mapping X-rays by Position-Tagged Spectrometry J. Microsc. 193 2–14. The first commercial SI softwareGoogle Scholar
  14. Newbury DE 1995 Artifacts in Energy Dispersive X-Ray Spectrometry in Electron Beam Instruments; Are Things Getting Any Better? in X-Ray Spectrometry in Electron Beam Instruments DB Williams, JI Goldstein and DE Newbury (Eds.) 167–201 Plenum Press New York. Discussion of artifacts and how digital imaging changes them.Google Scholar
  15. Newbury, DE 2005 X-ray Spectrometry and Spectrum Image Mapping at Output Count Rates above 100 kHz with a Silicon Drift Detector on a Scanning Electron Microscope Scanning 27 227–239. SDD performance.Google Scholar
  16. Reese, GM, Spence, JCH and Yamamoto, N 1984 Coherent Bremsstrahlung from Kilovolt Electrons in Zone Axis Orientations Phil. Mag. A 49 697–716. Early demonstration of CB.Google Scholar
  17. Williams, DB and Goldstein, JI 1981 Artifacts Encountered in Energy Dispersive X-ray Spectrometry in the Analytical Electron Microscopy in Energy Dispersive X-ray Spectrometry 341–349 Eds. KFJ Heinrich, DE Newbury, RL Myklebust and CE Fiori NBS Special Publication 604 U.S. Department of Commerce/NBS Washington D.C. Early review of system artifacts.Google Scholar
  18. Wittig, JE, Al-Sharaba, JF, Doerner, M, Bian, X, Bentley, J and Evans, ND 2003 Influence of Microstructure on the Chemical Inhomogeneities in Nanostructured Longitudinal Magnetic Recording Media Scripta Mater. 48 943–948. Early example of SI.Google Scholar
  19. Zemyan, SM and Williams, DB 1995 Characterizing an Energy-Dispersive Spectrometer on an Analytical Electron Microscope in X-Ray Spectrometry in Electron Beam Instruments DB Williams, JI Goldstein and DE Newbury (Eds.) 203–219 Plenum Press New York. Basic understanding of XEDS performance.Google Scholar

Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  1. 1.The University of Alabama in HuntsvilleHuntsvilleUSA
  2. 2.University of ConnecticutStorrsUSA

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