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Alloying mechanisms for epitaxial nanocrystals

M. S. Leite·G. Medeiros-Ribeiro·T. I. Kamins·R. Stanley Williams
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Abstract

The different mechanisms involved in the alloying of epitaxial nanocrystals are reported in this letter. Intermixing during growth, surface diffusion and intra-island diffusion were investigated by varying the growth conditions and annealing environments during chemical vapor deposition. The relative importance of each mechanism was evaluated in determining a particular composition profile for dome-shaped Ge:Si (001) islands. For samples grown at a faster rate, intermixing during growth was reduced. Si surface diffusion dominates during H$_2$ annealing whereas Ge surface diffusion and intra-island diffusion prevail during annealing in a PH$_3$ environment.

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M. S. Leite, G. Medeiros-Ribeiro, T. I. Kamins, R. Stanley Williams. 2007-01-30. Alloying mechanisms for epitaxial nanocrystals. https://arxiv.org/abs/cond-mat/0701710

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