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arXiv · 1205.1896

Strain relaxation by dislocation glide in ZnO/ZnMgO core-shell nanowires

Guillaume Perillat-Merceroz·Robin Thierry·Pierre-Henri Jouneau·Pierre Ferret·Guy Feuillet
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Abstract

Plastic relaxation of the misfit stress in core-shell semi-conducting nanowires can lead to structural defects, detrimental to applications. Core-shell Zn{0.7}Mg{0.3}O/ZnO quantum well heterostructures were deposited on ZnO nanowires. Strain along the a and c axes of the wurtzite structure is relaxed through the glide of dislocation half-loops from the free surfaces, within pyramidal and prismatic planes. Some half-loops are closed up in the barriers to accommodate the misfit at two consecutive interfaces of the quantum well stack. Dislocations are also observed within the nanowire core: contrary to two-dimensional structures, both the core and the shell can be plastically relaxed.

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Guillaume Perillat-Merceroz, Robin Thierry, Pierre-Henri Jouneau, Pierre Ferret, Guy Feuillet. 2012-05-09. Strain relaxation by dislocation glide in ZnO/ZnMgO core-shell nanowires. https://doi.org/10.1063/1.4704927

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