X-ray nanodiffraction at individual SiGe/Si(001) dot molecules and its numerical description based on kinematical scattering theory

摘要

Individual self-assembled SiGe/Si(001) dot molecules were investigated by scanning x-ray nanodiffraction with a beam size of 250 nm in diameter (full width at half maximum). The samples contain dot molecules with either one, two, three, or four dots. Different azimuthal configurations were measured and compared with simulated diffraction patterns. We have combined finite element calculations, kinematic scattering simulations, and experimental measurements to obtain information about lateral positional correlation as well as strain and germanium content within individual dot molecules.