Figure 3
TEM characterisation of epitaxially buried nanowire structure.
(a) Stitched BF TEM survey micrograph of a representative buried nanostructure imaged across the longitudinal cross-section, revealing the presence of a complex subsurface nanostructure initiated mid-way through growth at a compositional step. The various compositions displayed are determined through a combination of EDS, HRXRD and PL analysis. (b) Normalised intensity line scan (bottom) of a HAADF (Z-contrast) TEM image (top) recorded at the start of the nanowire, as indicated in (a). (c) HAADF TEM images recorded along the [110] zone axis at the five locations indicated in (a), with the insets showing the results of the FFT image reconstructions. (d) HAADF TEM image recorded at the termination of the nanowire growth, as shown in (a), with the angle indicating the front growth facet belonging to the {111} family. The dashed arrows in the Z-contrast images contained in (b,d) highlight the Bi composition step position, appearing approximately half way through the epitaxial layer.
