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arXiv · 0908.0883

Atomic structure of Ge quantum dots on the Si(001) surface

Larisa V Arapkina·Vladimir A Yuryev
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Abstract

In situ morphological investigation of the {105} faceted Ge islands on the Si(001) surface (hut clusters) have been carried out using an ultra high vacuum instrument integrating a high resolution scanning tunnelling microscope and a molecular beam epitaxy vessel. Both species of hut clusters--pyramids and wedges--were found to have the same structure of the {105} facets which was visualized. Structures of vertexes of the pyramidal clusters and ridges of the wedge-shaped clusters were revealed as well and found to be different. This allowed us to propose a crystallographic model of the {105} facets as well as models of the atomic structure of both species of the hut clusters. An inference is made that transitions between the cluster shapes are impossible.

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Larisa V Arapkina, Vladimir A Yuryev. 2010-02-25. Atomic structure of Ge quantum dots on the Si(001) surface. https://doi.org/10.1134/s0021364010060056

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