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Chemical mapping at atomic resolution using energy-dispersive x-ray spectroscopy

Published online by Cambridge University Press:  13 January 2012

Leslie J. Allen ,
Adrian J. D’Alfonso ,
Bert Freitag  and
Dmitri O. Klenov
Leslie J. Allen
Affiliation:
School of Physics, University of Melbourne; lja@unimelb.edu.au
Adrian J. D’Alfonso
Affiliation:
School of Physics, University of Melbourne; adrian@dalfonso.com.au
Bert Freitag
Affiliation:
FEI Company, The Netherlands; Bert.Freitag@fei.com
Dmitri O. Klenov
Affiliation:
FEI Company, The Netherlands; Dmitri.O.Klenov@fei.com
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Abstract

We review the recently introduced technique of atomic-resolution chemical mapping in scanning transmission electron microscopy (STEM) based on energy-dispersive x-ray spectroscopy. Working at the atomic level is facilitated by ultrasensitive energy-dispersive x-ray detectors in combination with Cs-correction of the STEM probe. Details of the experimental implementation are discussed, and a theoretical framework within which the measured results can be understood is described. Three case studies are presented: the analysis of specimens of GaAs and SrTiO3, as well as examination of an interface between SrTiO3 and PbTiO3. Detailed theoretical simulations of the imaging process show that the projected positions of elements in atomic columns can be directly deduced from the chemical maps. For the core shells used, the effective ionization interaction is local and generally localized in the vicinity of the atoms being ionized. The local nature of the effective ionization potential means that this is an incoherent mode of imaging, akin to Z-contrast imaging but with additional chemical information.

Keywords

Chemical compositioncrystallographic structurescanning transmission electron microscopy
Type
Research Article
Information
MRS Bulletin , Volume 37 , Issue 1: Spectroscopic imaging in electron microscopy , January 2012 , pp. 47 - 52
Copyright
Copyright © Materials Research Society 2012

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References

1.Pennycook, S.J., in Scanning Transmission Electron Microscopy: Imaging and Analysis, Pennycook, S.J., Nellist, P.D., Eds. (Springer, NY, 2011), p. 1.Google Scholar
2.Allen, L.J., Findlay, S.D., Oxley, M.P., in Scanning Transmission Electron Microscopy: Imaging and Analysis, Pennycook, S.J., Nellist, P.D., Eds. (Springer, NY 2011), p. 247.CrossRefGoogle Scholar
3.D’Alfonso, A.J., Freitag, B., Klenov, D., Allen, L.J., Phys. Rev. B 81, 100101R (2010).Google Scholar
4.Chu, M.-W., Liou, S. C., Chang, C.-P., Choa, F.-S., Chen, C.H., Phys. Rev. Lett. 104, 196101 (2010).CrossRefGoogle Scholar
5.von Harrach, H.S., Dona, P., Freitag, B., Niculae, A., Rohde, M., Microsc. Microanal. 15 (Suppl. 2), 208 (2009).CrossRefGoogle Scholar
6.Schlossmacher, P., Klenov, D.O., Freitag, B., von Harrach, S., Microsc. Today 18, 14 (2010).Google Scholar
7.Schlossmacher, P., Klenov, D.O., Freitag, B., von Harrach, S., Steinbach, A., Microsc. Anal. (Nanotechnology Supplement) 24, S5 (2010).Google Scholar
8.Kujawa, S., Freitag, B., Hubert, D., Microsc. Today 13, 16 (2005).Google Scholar
9.Freitag, B., Erni, R., Inoke, K., Stekelenburg, M., Hubert, D., Microscopy 41, 21 (2006).Google Scholar
10.Hawkes, P.W., Phil. Trans. R. Soc. A 367, 3637 (2009).Google Scholar
11.Forbes, B.D., Martin, A.V., Findlay, S.D., D’Alfonso, A.J., Allen, L.J., Phys. Rev. B 82, 104103 (2010).CrossRefGoogle Scholar
12.Oxley, M.P., Allen, L.J.. Phys. Rev. B 57, 3273 (1998).Google Scholar
13.Allen, L.J., Findlay, S.D., Oxley, M.P., Rossouw, C.J., Ultramicroscopy 96, 47 (2003).Google Scholar
14.Findlay, S.D., Oxley, M.P., Pennycook, S.J., Allen, L.J., Ultramicroscopy 104, 126 (2005).CrossRefGoogle Scholar
15.Hillyard, S., Loane, R.F., Silcox, J., Ultramicroscopy 49, 14 (1993).Google Scholar
16.Kirkland, E.J., Advanced Computing in Electron Microscopy (Plenum Press, NY, 1998).Google Scholar
17.Findlay, S.D., Oxley, M.P., Allen, L.J., Microsc. Microanal. 14, 48 (2006).Google Scholar
18.Wang, P., D’Alfonso, A.J., Findlay, S.D., Allen, L.J., Bleloch, A.L., Phys. Rev. Lett. 101, 236102 (2008).CrossRefGoogle Scholar
19.Freitag, B., Klenov, D., von Harrach, H.S., D’Alfonso, A.J., Allen, L.J., Proceedings, Microscopy Conference 2011, Kiel, August-September 2011, contribution IM1.113.Google Scholar
20.Klenov, D., Lazar, S., Microscopy and Analysis (Asia Pacific Issue), 82, p. 3 (John Wiley, Chichester, 2011).Google Scholar
21.Klenov, D.O., Stemmer, S., Ultramicroscopy 106, 889 (2006).Google Scholar
22.Klenov, D.O., Findlay, S.D., Allen, L.J., Stemmer, S., Phys. Rev. B 76, 014111 (2007).CrossRefGoogle Scholar
23.LeBeau, J.M., Findlay, S.D., Allen, L.J., Stemmer, S., Phys. Rev. Lett. 100, 206101 (2008).CrossRefGoogle Scholar
24.Klenov, D., Freitag, B., von Harrach, H. S., D’Alfonso, A.J., Allen, L.J., Microsc. Microanal. 17 (Suppl. 2), 598 (2011).CrossRefGoogle Scholar