Faceting of InAs-InSb Heterostructured Nanowires

We report on the morphology of InAs-InSb heterostructured nanowires grown by Au-assisted chemical beam epitaxy. Using scanning and transmission electron microscopy, along with high angle annular dark field image analysis, we show that the hexagons defining the cross section of the two segments of the nanowires are rotated one with respect to the other by 30° around the growth direction and that the corners of these hexagons are rounded off by six small facets. Six additional facets that are not parallel to the growth direction are found in the InSb segment at the InAs-InSb interface and are indexed. Finally, the relation between the dimensions of the two segments composing the nanowires is discussed quantitatively.