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Convergent-Beam Low Energy Electron Diffraction (CBLEED) and the Measurement of Surface Dipole Layers

Published online by Cambridge University Press:  22 January 2004

J.C.H. Spence ,
H.C. Poon  and
D.K. Saldin
J.C.H. Spence
Affiliation:
Department of Physics and Astronomy, College of Liberal Arts and Science, Arizona State University, Tempe, AZ 85287-1504, USA
H.C. Poon
Affiliation:
Department of Physics and Laboratory for Surface Studies, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, USA
D.K. Saldin
Affiliation:
Department of Physics and Laboratory for Surface Studies, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, USA
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Abstract

We propose the formation of LEED patterns using a highly convergent beam forming a probe of nanometer dimensions. A reflection rocking curve may then be recorded in many diffraction orders simultaneously. Multiple scattering calculations show that the intensity variations within these rocking curves is as sensitive to the parameters describing the surface dipole layer as conventional I/V scans. However the data may be collected from areas sufficiently small to avoid defects and surface steps, radiation damage controlled by use of low voltages, and the information depth selected by choice of the (constant) voltage. We briefly discuss also the application of this method to oxides and the formation of atomic-resolution scanning images in an idealized instrument in which coherent diffracted LEED orders overlap.

Keywords

LEEDconvergent beamnanoprobedipole layer
Type
Research Article
Information
Microscopy and Microanalysis , Volume 10 , Issue 1 , February 2004 , pp. 128 - 133
Copyright
© 2004 Microscopy Society of America

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References

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