Quantitative analysis of the quantum dot superlattice by high-resolution x-ray diffraction

A new high-resolution x-ray diffraction approach for quantitative analysis of superlattice structures (SLs) with self-assembled quantum dots (QDs) was developed. For numerical simulations of the 2D angular distribution of diffracted x-ray radiation, both the coherent and diffuse scattering components have been calculated. Direct comparison of simulated patterns and experimental results revealed good agreement of the calculated intensity distribution with experimental reciprocal space maps for the superlattice GaAs(001)-AlGaAs-{InAs QDs-GaAs}(SL) with 20 periods of quantum dots. The simulation procedure allows one to obtain data about the shape, average size, elastic strains around the QDs, average density of the QDs, the presence of short-or long-range order in the arrangement of QDs in the semiconducting matrix, the vertical and lateral correlation lengths of the ensemble of quantum dots, and the parameters of the intermediate GaAs and AlGaAs layers. (C) 2013 AIP Publishing LLC.