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arXiv · 0803.1951

Direct evidence of enhanced Ga interdiffusion in InAs vertically aligned free-standing nanowires

J. C. Gonz'alez·A. Malachias·J. C. de Sousa·R-Ribeiro Andrade·M. V. B. Moreira·A. G. de Oliveira
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Abstract

We present direct evidence of enhanced Ga interdiffusion in InAs free-standing nanowires grown at moderate temperatures by molecular beam epitaxy on GaAs (111)B. Scanning electron microscopy together with X-ray diffraction measurements in coplanar and grazing incidence geometries show that nominally grown InAs NWs are actually made of In$_{0.86}$Ga$_{0.14}$As. Unlike typical vapor-liquid-solid growth, these nanowires are formed by diffusion-induced growth combined with strong interdiffusion from substrate material. Based on the experimental results, a simple nanowire growth model accounting for the Ga interdiffusion is also presented. This growth model could be generally applicable to the molecular beam heteroepitaxy of III-V nanowires.

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J. C. Gonz'alez, A. Malachias, J. C. de Sousa, R-Ribeiro Andrade, M. V. B. Moreira, A. G. de Oliveira. 2008-05-14. Direct evidence of enhanced Ga interdiffusion in InAs vertically aligned free-standing nanowires. https://arxiv.org/abs/0803.1951

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