Dynamical X-Ray Diffraction Characterization of the Self-Organized Quantum Dot Formation In Imperfect Semiconductor Superlattices

Abstract

The self-organized quantum dot (QD) formation in InGaAs/GaAs superlattices grown by molecular beam epitaxy was investigated by the high-resolution X-ray diffraction technique. The investigated samples had the identical structure consisting of fifteen periods of {InxGa1−xAs (8 ML)/GaAs (26 ML)} with the nominal In concentration x = 0.2. The diffraction profiles and reciprocal lattice maps for these samples have been measured at symmetrical (004) reflection by using the triple-crystal X-ray diffractometer. The analysis of the measured data was performed by using the proposed diffraction model based on the statistical theory of dynamical X-ray scattering in imperfect single crystals and multilayer structures.