Controlled dislocation slipping: an original method to create multiple quantum wire structures

Abstract

We propose an original method to fabricate one-dimensional (1D) semiconductor nanostructures using dislocations, generated by plastic deformation, as atomic scale saws to cut a 2D-structure into a multiple quantum wire structure. The 2D-structure used to apply this method is a 5 nm GaAs/GaAlAs quantum well grown by molecular beam epitaxy on a (001) GaAs substrate.The photoluminescence (PL) spectrum of the plastically deformed quantum well exhibits an 8 meV blue shift of the exciton peak, compared to the PL spectrum of the quantum well before deformation. The statistical analysis of transmission electron microscopy cross-section observations reveals a communicating multiple quantum wire structure (or lateral superlattice), composed of coupled GaAs/GaAlAs quantum wires of 18±9 nm width.A calculation of the 1D-confinement levels, based on the tight binding method, confirms the creation of such a lateral superlattice by correlating quantitatively the PL results with microscopy observations.