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arXiv · 1312.4809

Investigation of III-V Nanowires by Plan-View Transmission Electron Microscopy: InN Case Study

E Luna·J Grandal·E Gallardo·J M Calleja·M A Sánchez-García·E Calleja·A Trampert
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Abstract

We discuss observations of InN nanowires (NWs) by plan-view high-resolution transmission electron microscopy (TEM). The main difficulties arise from suitable methods available for plan-view specimen preparation. We explore different approaches and find that the best results are obtained using a refined preparation method based on the conventional procedure for plan-view TEM of thin films, specifically modified for the NW morphology. The fundamental aspects of such a preparation are the initial mechanical stabilization of the NWs and the minimization of the ion-milling process after dimpling the samples until perforation. The combined analysis by plan-view and cross-sectional TEM of the NWs allows determination of the degree of strain relaxation and reveals the formation of an unintentional shell layer (2-3 nm thick) around the InN NWs. The shell layer is composed of bcc-In2O3 nanocrystals with a preferred orientation with respect to the wurtzite InN: In2O3 [111] || InN [0001] and In2O3 <110> || InN <11-20>.

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E Luna, J Grandal, E Gallardo, J M Calleja, M A Sánchez-García, E Calleja, A Trampert. 2014-09-29. Investigation of III-V Nanowires by Plan-View Transmission Electron Microscopy: InN Case Study. https://doi.org/10.1017/s1431927614013038

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