Lattice mismatch and interfacial disorder in superlattices

We have developed a general X-ray diffraction model which enables to investigate interfacial disorder in crystalline/amorphous and crystalline/crystalline multilayers. Using classical structure factor calculations, we simulate the evolution of the diffracted X-ray intensities as a function of the fluctuation amplitude, the superlattice wavelength and the interatomic distances. From experimental X-ray diffraction patterns, the interfacial disorder is extracted as a function of superlattice wavelength for various crystalline/crystalline systems. An enhanced lattice mismatch between the two components gives rise to an increase of interfacial disorder.