Elastic vs. plastic strain relaxation in coalesced GaN nanowires: an x-ray diffraction study

Abstract

The coalescence in dense arrays of spontaneously formed GaN nanowires proceeds by bundling: adjacent nanowires bend and merge at their top, thus reducing their surface energy at the expense of the elastic energy of bending. We give a theoretical description of the energetics of this bundling process. The bending energy is shown to be substantially reduced by the creation of dislocations at the coalescence joints. A comparison of experimental and calculated x-ray diffraction profiles from ensembles of bundled nanowires demonstrates that a large part of the bending energy is indeed relaxed by plastic deformation. The residual bending manifests itself by extended tails of the diffraction profiles.

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Cited by in corpus (1)

• Self-Assembled formation of long, thin, and uncoalesced GaN nanowires on crystalline TiN films