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Atomic ordering in self-assembled Ge:Si(001) islands observed by X-ray scattering

A. Malachias·T. U. Schulli·G. Medeiros-Ribeiro·M. Stoffel·O. G. Schmidt·T. H. Metzger·R. Magalhaes-Paniago
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Abstract

X-ray diffuse scattering in the vicinity of a basis-forbidden (200) Bragg reflection was measured for a sample with uncapped self-assembled Ge islands epitaxially grown on Si(001). Our results provide evidence of atomically ordered SiGe domains in both islands and wetting layer. The modeling of x-ray profiles reveals the presence of antiphase boundaries separating the ordered domains in a limited region of the islands where the stoichiometry is close to Si0.5Ge0.5.

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A. Malachias, T. U. Schulli, G. Medeiros-Ribeiro, M. Stoffel, O. G. Schmidt, T. H. Metzger, R. Magalhaes-Paniago. 2004-11-25. Atomic ordering in self-assembled Ge:Si(001) islands observed by X-ray scattering. https://arxiv.org/abs/cond-mat/0411642

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