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Prepyramid-to-pyramid transition of SiGe islands on Si(001)

A. Rastelli·H. von Kaenel·B. J. Spencer·J. Tersoff
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Abstract

The morphology of the first three-dimensional islands appearing during strained growth of SiGe alloys on Si(001) was investigated by scanning tunneling microscopy. High resolution images of individual islands and a statistical analysis of island shapes were used to reconstruct the evolution of the island shape as a function of size. As they grow, islands undergo a transition from completely unfacetted rough mounds (prepyramids) to partially {105} facetted islands and then they gradually evolve to {105} facetted pyramids. The results are in good agreement with the predictions of a recently proposed theoretical model.

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A. Rastelli, H. von Kaenel, B. J. Spencer, J. Tersoff. 2003-08-14. Prepyramid-to-pyramid transition of SiGe islands on Si(001). https://doi.org/10.1103/physrevb.68.115301

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