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

Guillaume Perillat-Merceroz (1, 2) , Robin Thierry (1) , Pierre-Henri Jouneau (2) , Pierre Ferret (1) , Guy Feuillet (1)

1 CEA-LETI - Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information
2 LEMMA - Laboratoire d'Etude des Matériaux par Microscopie Avancée

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.

Mots clés: dislocations; II-VI semiconductors; nanowires; quantum wells; semiconductor quantum wells; slip; wide band gap semiconductors; zinc compounds

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Guillaume Perillat-Merceroz, Robin Thierry, Pierre-Henri Jouneau, Pierre Ferret, Guy Feuillet. Strain relaxation by dislocation glide in ZnO/ZnMgO core-shell nanowires. Applied Physics Letters, 2012, 100 (17), pp.173102. ⟨10.1063/1.4704927⟩. ⟨hal-00691440⟩