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Effect of Two-Dimensionality on Step Bunching Induced by the Drift of Adatoms

Masahide Sato·Makio Uwaha·Yukio Hirose
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Abstract

We study the effect of two-dimensionality on step bunching induced by drift of adatoms. When anisotropy of the diffusion coefficient changes alternately on consecutive terraces like a Si(001) vicinal face, bunching occurs with the drift of adatoms. If the fluctuation of step bunches is neglected as in the one-dimensional model, the bunching with step-down drift is faster than that with step-up drift in contradiction with the experiment by Latyshev and coworkers. In a two-dimensional model, the step bunches wander heavily with step-up drift and recombination with neighboring bunches occur more frequently than those with step-down drift and the bunching is accelerated. When the difference of kinetic coefficients between two types of steps is taken into account, the bunching with step-up drift can be faster than that with step-down drift.

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Masahide Sato, Makio Uwaha, Yukio Hirose. 2005-06-23. Effect of Two-Dimensionality on Step Bunching Induced by the Drift of Adatoms. https://arxiv.org/abs/cond-mat/0506592

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