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Atomically straight steps on vicinal Si (111) surfaces prepared by step-parallel current in the kink-up direction

S. Yoshida·T. Sekiguchi·K. M. Itoh
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Abstract

We demonstrate that annealing of a vicinal Si(111) surface at about 800 C with a direct current in the direction that ascends the kinks enhances the formation of atomically straight step edges over micrometer lengths, while annealing with a current in the opposite direction does not. Every straight step edge has the same atomic configuration U(2,0), which is useful as a template for the formation of a variety of nanostructures. A phenomenological model based on electromigration of charged mobile atoms explains the observed current-polarity dependent behavior.

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S. Yoshida, T. Sekiguchi, K. M. Itoh. 2005-07-11. Atomically straight steps on vicinal Si (111) surfaces prepared by step-parallel current in the kink-up direction. https://doi.org/10.1063/1.1995946

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