Hostname: page-component-78c5997874-xbtfd Total loading time: 0 Render date: 2024-11-15T23:26:09.819Z Has data issue: false hasContentIssue false
  • English
  • Français

Chemical Quantification of Atomic-Scale EDS Maps under Thin Specimen Conditions

Published online by Cambridge University Press:  13 October 2014

Ping Lu ,
Eric Romero ,
Shinbuhm Lee ,
Judith L. MacManus-Driscoll  and
Quanxi Jia
Ping Lu*
Affiliation:
Sandia National Laboratories, PO Box 5800, MS 1411, Albuquerque, NM 87185-1411, USA
Eric Romero
Affiliation:
Sandia National Laboratories, PO Box 5800, MS 1411, Albuquerque, NM 87185-1411, USA
Shinbuhm Lee
Affiliation:
Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, UK
Judith L. MacManus-Driscoll
Affiliation:
Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, UK
Quanxi Jia
Affiliation:
Los Alamos National Laboratory, Center for Integrated Nanotechnologies, Los Alamos, NM 87545, USA
*
*Corresponding author. [email protected]
Get access

Abstract

We report our effort to quantify atomic-scale chemical maps obtained by collecting energy-dispersive X-ray spectra (EDS) using scanning transmission electron microscopy (STEM) (STEM-EDS). With thin specimen conditions and localized EDS scattering potential, the X-ray counts from atomic columns can be properly counted by fitting Gaussian peaks at the atomic columns, and can then be used for site-by-site chemical quantification. The effects of specimen thickness and X-ray energy on the Gaussian peak width are investigated using SrTiO3 (STO) as a model specimen. The relationship between the peak width and spatial resolution of an EDS map is also studied. Furthermore, the method developed by this work is applied to study cation occupancy in a Sm-doped STO thin film and antiphase boundaries (APBs) present within the STO film. We find that Sm atoms occupy both Sr and Ti sites but preferably the Sr sites, and Sm atoms are relatively depleted at the APBs likely owing to the effect of strain.

Keywords

atomic-scale mappingEDSchemical quantificationSrTiO3antiphase boundaries
Type
Materials Applications
Information
Microscopy and Microanalysis , Volume 20 , Issue 6 , December 2014 , pp. 1782 - 1790
Copyright
© Microscopy Society of America 2014 

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

Allen, L.J., D’Alfonso, A.J., Freitag, B. & Klenov, D.O. (2012). Chemcial mapping at atomic resolution using energy-dispersive x-ray spectroscopy. MRS Bulletin 37, 47–52.Google Scholar
Bosman, M., Keast, Y.J., Garcia-Munoz, J.L., D’Afonso, A.J., Findlay, S.D. & Allen, L.J. (2007). Two-dimensional mapping of chemical information at atomic resolution. Phys Rev Lett 99, 086102.Google Scholar
Browning, N.D., Chisholm, M.F. & Pennycook, S.J. (1993). Atomic-resolution chemical analysis using a scanning transmission electron microscope. Nature 366, 143–146.CrossRefGoogle Scholar
Chu, M.W., Liou, S.C., Chang, C.P., Choa, F.S. & Chen, C.H. (2010). Emergent chemical mapping at atomic-column resolution by energy-dispersive x-ray spectroscopy in an aberration-corrected electron microscope. Phys Rev Lett 104, 196101.CrossRefGoogle Scholar
Cliff, G. & Lorimer, G.W. (1975). The quantitative analysis of thin specimen. J Microsc 103, 203–207.CrossRefGoogle Scholar
D’Alfonso, A.J., Freitag, B., Klenov, V. & Allen, L.J. (2010). Atomic-resolution chemical mapping using energy-dispersive x-ray spectroscopy. Phys Rev B 81, 100101.Google Scholar
Forbes, B.D., D’Alfonso, A.J., Williams, R.E.A., Srinivasan, R., Fraser, H.L., McComb, D.W., Freitag, B., Klenov, D.O. & Allen, L.J. (2012). Contribution of thermally scattered electrons to atomic resolution elemental maps. Phys Rev B86, 24108.Google Scholar
Kimoto, K., Asaka, T., Nagai, T., Saito, M., Matsui, Y. & Ishizuka, K. (2007). Element-selective imaging of atomic columns in a crystal using STEM and EELS. Nature 450, 702–704.Google Scholar
Klenov, D.O. & Zide, J.M.O. (2011). Structure of the InAlAs/InP interface by atomically resolved energy dispersive spectroscopy. App Phys Lett 99, 141904.Google Scholar
Kothleitner, G., Neish, M.J., Lugg, N.R., Finflay, S.D., Grogger, W., Hofer, F. & Allen, L.J. (2014). Quantitative elemental mapping at atomic resolution using X-ray spectroscopy. Phy Rev Lett 112, 085501.Google Scholar
Kotula, P., Klenov, D.O. & Von Harrach, H.S. (2012). Challenges to quantitative multivariate statistical analysis of atomic-resolution X-ray spectral images. Microsc Microanal 18, 691–698.Google Scholar
Lu, P., Xiong, J., Van Benthem, M. & Jia, Q.X. (2013). Atomic-scale chemical quantification of oxide interfaces using energy-dispersive X-ray spectroscopy. App Phys Lett 102, 173111.Google Scholar
Lu, P., Zhou, L., Kramer, M.J. & Smith, D.J. (2014). Atomic-scale chemical imaging and quantification of metallic alloy structures by energy-dispersive X-ray spectroscopy. Sci Rep 4, 3945–3949.CrossRefGoogle ScholarPubMed
Muller, D.A., Fitting Kourkoutis, L., Murfitt, M., Song, J.H., Hwang, H.Y., Silcox, J., Dellby, N. & Krivanek, O.L. (2008). Atomic-scale chemical imaging of composition and bonding by aberration-corrected microscopy. Science 319, 1073–1076.Google Scholar
Oxley, M.P., Varela, M., Pennycook, T.J., Van Benthem, K., Findlay, S.D., D’Alfonso, A.J., Allen, L.J. & Pennycook, S.J. (2007). Interpreting atomic-resolution spectroscopic images. Phys Rev B76, 64303–64311.Google Scholar
Rose, A. (1948). In Advances in Electronics, Marton A. (Ed.), pp. 131. New York: Academic Press.Google Scholar
Shah, A.B., Ramasse, Q.M., Zhai, X.F., Wen, J.G., May, S.J., Petrov, I., Bhattacharya, A., Abbamonte, P., Eckstein, J.N. & Zuo, J.M. (2012). Probing interfacial electronic structures in atomic layer LaMnO3 and SrTiO3 superlattices. Adv Mater 22, 1156–1160.Google Scholar
Von Harrach, H.S., Dona, P., Freitag, B., Soltau, H., Niculae, A. & Rohde, M. (2009). An integrated silicon drift detector system for FEI Schottky field emission transmission electron microscopes. Microsc Microanal 15(Suppl 2), 208–209.Google Scholar
Wang, P., D’Alfonso, A.J., Findlay, S.D., Allen, L.J. & Bleloch, A.L. (2008). Contrast reversal in atomic-resolution chemical mapping. Phys Rev Lett 101, 236102.Google Scholar
Watanabe, M., Kanno, M. & Okunishi, E. (2010). Atomic-resolution elemental mapping by EELS and XEDS in aberration corrected STEM. JEOL News 45, 8–15.Google Scholar
Williams, B. & Carter, C.B. (2009). Transmission electron microscopy: A textbook for materials science, 2nd ed. New York: Springer.Google Scholar