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Cold Alchemi: Impurity Atom Site Location and the Temperature Dependance of Dechannelling

Published online by Cambridge University Press:  25 February 2011

J. C. H. Spence
Affiliation:
Department of Physics, Arizona State University, Tempe, Arizona 85287, USA
R. J. Graham
Affiliation:
Department of Physics, Arizona State University, Tempe, Arizona 85287, USA
D. Shindo
Affiliation:
Department of Physics, Arizona State University, Tempe, Arizona 85287, USA
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Abstract

Recent applications of the “Atom Location by Channelling Enhanced Microanalysis” (ALCHEMI) are summarised. This is a quantitative method for determining the sites of impurity atoms in crystals using an electron microscope and X-ray analysis system. Since the fractional site occupancies are given in terms of measured X-ray counts alone, it involves no adjustable parameters. New experiments have been performed on the temperature dependence of characteristic X-ray production under channelling conditions for InP and GaAs. We conclude that low temperatures will give more accurate results for “ALCHEMI” in some materials due to the reduction in diffuse inelastic phonon scattering, and that the study of this temperature dependence may provide new information from small areas or particles on the correlations amongst atom motions due to thermal vibration.

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Articles
Copyright
Copyright © Materials Research Society 1986

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