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Initial stage of the 2D-3D transition of a strained SiGe layer on a pit-patterned Si(001) template

Gang Chen·Herbert Lichtenberger·Guenther Bauer·Wolfgang Jantsch·Friedrich Schaffler
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Abstract

We investigate the initial stage of the 2D-3D transition of strained Ge layers deposited on pit-patterned Si(001) templates. Within the pits, which assume the shape of inverted, truncated pyramids after optimized growth of a Si buffer layer, the Ge wetting layer develops a complex morphology consisting exclusively of {105} and (001) facets. These results are attributed to a strain-driven step-meandering instability on the facetted side-walls of the pits, and a step-bunching instability at the sharp concave intersections of these facets. Although both instabilities are strain-driven, their coexistence becomes mainly possible by the geometrical restrictions in the pits. It is shown that the morphological transformation of the pit surface into low-energy facets has strong influence on the preferential nucleation of Ge islands at the flat bottom of the pits.

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Gang Chen, Herbert Lichtenberger, Guenther Bauer, Wolfgang Jantsch, Friedrich Schaffler. 2006-02-07. Initial stage of the 2D-3D transition of a strained SiGe layer on a pit-patterned Si(001) template. https://doi.org/10.1103/physrevb.74.035302

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