Hostname: page-component-586b7cd67f-g8jcs Total loading time: 0 Render date: 2024-12-07T11:29:51.808Z Has data issue: false hasContentIssue false

Modeling Atomic-Resolution Scanning Transmission Electron Microscopy Images

Published online by Cambridge University Press:  21 December 2007

Scott D. Findlay
Affiliation:
School of Physics, University of Melbourne, Victoria 3010, Australia
Mark P. Oxley
Affiliation:
Materials Science and Technology Division, Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831, USA
Leslie J. Allen
Affiliation:
School of Physics, University of Melbourne, Victoria 3010, Australia
Get access

Abstract

A real-space description of inelastic scattering in scanning transmission electron microscopy is derived with particular attention given to the implementation of the projected potential approximation. A hierarchy of approximations to expressions for inelastic images is presented. Emphasis is placed on the conditions that must hold in each case. The expressions that justify the most direct, visual interpretation of experimental data are also the most approximate. Therefore, caution must be exercised in selecting experimental parameters that validate the approximations needed for the analysis technique used. To make the most direct, visual interpretation of electron-energy-loss spectroscopic images from core-shell excitations requires detector improvements commensurate with those that aberration correction provides for the probe-forming lens. Such conditions can be relaxed when detailed simulations are performed as part of the analysis of experimental data.

Type
Research Article
Copyright
© 2008 Microscopy Society of America

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

REFERENCES

Allen, L.J., Findlay, S.D., Oxley, M.P. & Rossouw, C.J. (2003). Lattice-resolution contrast from a focused coherent electron probe. Part I. Ultramicroscopy 96, 4763.Google Scholar
Allen, L.J., Findlay, S.D., Witte, C., Oxley, M.P. & Zaluzec, N.J. (2006). Modelling high-resolution electron microscopy based on core-loss spectroscopy. Ultramicroscopy 106, 10011011.Google Scholar
Allen, L.J. & Josefsson, T.W. (1995). Inelastic scattering of fast electrons by crystals. Phys Rev B 52, 31843198.Google Scholar
Batson, P.E., Dellby, N. & Krivanek, O.L. (2002). Sub-ångstrom resolution using aberration corrected electron optics. Nature 418, 617620.Google Scholar
Borisevich, A.Y., Lupini, A.R., Travaglini, S. & Pennycook, S.J. (2006). Depth sectioning of aligned crystals with the aberration-corrected scanning transmission electron microscope. J Electron Microsc 55, 712.Google Scholar
Cherns, D., Howie, A. & Jacobs, M.H. (1973). Characteristic X-ray production in thin crystals. Z Naturforsch A 28, 565571.Google Scholar
Coene, W. & Van Dyck, D. (1990). Inelastic scattering of high-energy electrons in real space. Ultramicroscopy 33, 261267.Google Scholar
Cosgriff, E.C., Oxley, M.P., Allen, L.J. & Pennycook, S.J. (2005). The spatial resolution of imaging using core-loss spectroscopy in the scanning transmission electron microscope. Ultramicroscopy 102, 317326.Google Scholar
Dinges, C., Berger, A. & Rose, H. (1995). Simulation of TEM images considering phonon and electronic excitations. Ultramicroscopy 60, 4970.Google Scholar
Dudarev, S.L., Peng, L.-M. & Whelan, M.J. (1993). Correlations in space and time and dynamical diffraction of high-energy electrons by crystals. Phys Rev B 48, 1340813429.Google Scholar
Dwyer, C. (2005). Multislice theory of fast electron scattering incorporating atomic inner-shell ionization. Ultramicroscopy 104, 141151.Google Scholar
Dwyer, C. & Etheridge, J. (2003). Scattering of Å-scale electron probes in silicon. Ultramicroscopy 96, 343360.Google Scholar
Findlay, S.D., Oxley, M.P., Pennycook, S.J. & Allen, L.J. (2005). Modelling imaging based on core-loss spectroscopy in scanning transmission electron microscopy. Ultramicroscopy 104, 126140.Google Scholar
Ishizuka, K. (2001). Prospects of atomic resolution imaging with an aberration-corrected STEM. J Electron Microsc 50, 291305.Google Scholar
Jesson, D.E. & Pennycook, S.J. (1993). Incoherent imaging of thin specimens using coherently scattered electrons. Proc R Soc Lond A 441, 261281.Google Scholar
Kohl, H. & Rose, H. (1985). Theory of image formation by inelastic scattered electrons in the electron microscope. Adv Electronics Electron Phys 65, 173227.Google Scholar
Loane, R.F., Xu, P. & Silcox, J. (1992). Incoherent imaging of zone axis crystals with ADF STEM. Ultramicroscopy 40, 121138.Google Scholar
Lupini, A.R. & Pennycook, S.J. (2003). Localization in elastic and inelastic scattering. Ultramicroscopy 96, 313322.Google Scholar
Maslen, V.W. & Rossouw, C.J. (1984). Implications of (e,2e) scattering for inelastic electron diffraction in crystals. I. Theoretical. Philos Mag A 49, 735742.Google Scholar
McGibbon, A.J., Pennycook, S.J. & Jesson, D.E. (1999). Crystal structure retrieval by maximum entropy analysis of atomic resolution incoherent images. J Microsc 195, 4457.Google Scholar
Muller, D.A. & Silcox, J. (1995). Delocalization in inelastic scattering. Ultramicroscopy 59, 195213.Google Scholar
Müller, H., Rose, H. & Schorsch, P. (1998). A coherence function approach to image simulation. J Microsc 190, 7388.Google Scholar
Nellist, P.D. & Pennycook, S.J. (1999). Incoherent imaging using dynamically scattered coherent electrons. Ultramicroscopy 78, 111124.Google Scholar
Oxley, M.P. & Allen, L.J. (2001). Atomic scattering factors for K-shell electron energy-loss spectroscopy. Acta Cryst A 57, 713728.Google Scholar
Oxley, M.P., Cosgriff, E.C. & Allen, L.J. (2005). Nonlocality in imaging. Phys Rev Lett 94, 203906.Google Scholar
Peng, Y., Nellist, P.D. & Pennycook, S.J. (2004). HAADF-STEM imaging with sub-angstrom probes: A full Bloch wave analysis. J Electron Microsc 53, 257266.Google Scholar
Rez, P. (1978). Virtual inelastic scattering in high-energy electron diffraction. Acta Cryst A 34, 4851.Google Scholar
Rez, P., Humphries, C.J. & Whelan, M.J. (1977). The distribution of intensity in electron diffraction patterns due to phonon scattering. Philos Mag 35, 8196.Google Scholar
Schattschneider, P., Nelhiebel, M., Souchay, H. & Jouffrey, B. (2000). The physical significance of the mixed dynamic form factor. Micron 31, 333345.Google Scholar
Voyles, P.M., Muller, D.A. & Kirkland, E.J. (2004). Depth-dependent imaging of individual dopant atoms in silicon. Microsc Microanal 10, 291300.Google Scholar
Wang, Z.L. (1989). A multislice theory of electron inelastic scattering in a solid. Acta Cryst A 45, 636664.Google Scholar
Watanabe, K., Kotaka, Y., Nakanishi, N., Yamazaki, T., Hashimoto, I. & Shiojiri, M. (2002). Deconvolution processing of HAADF STEM images. Ultramicroscopy 92, 191199.Google Scholar
Yoshioka, H. (1957). Effect of inelastic waves on electron diffraction. J Phys Soc Japan 12, 618628.Google Scholar