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Two-dimensional imaging of the potential distribution within a core/shell nanowire by electron holography

Published online by Cambridge University Press:  01 May 2006

Jayhoon Chung
Affiliation:
Texas Materials Institute, University of Texas at Austin, Austin, Texas 78712
Lew Rabenberg*
Affiliation:
Texas Materials Institute, University of Texas at Austin, Austin, Texas 78712
*
a) Address all correspondence to this author. e-mail: [email protected]
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Abstract

Electrostatic potentials within a core/shell nanowire structure, composed of an intrinsic germanium core surrounded by its oxide and a heavily doped germanium shell, were investigated by electron holographic analysis on its cross-section. The potential distribution resulting from interface charges as well as dopants was successfully imaged. The surface potential, screening length, and doping concentration for the heavily doped germanium shell were determined quantitatively from the potential image. These characteristics were compared with values obtained from a numerical solution of Poisson's equation.

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Articles
Copyright
Copyright © Materials Research Society 2006

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