X-RAY TRIPLE-CRYSTAL DIFFRACTOMETRY OF DEFECTS IN EPITAXIAL LAYERS

A new method is developed for calculating the correlation function of the random deformation in heteroepitaxic layers and superlattices from measurements of iso-intensity contours of diffuse X-ray scattering. T he method is based on the optical coherence approach and kinematical d iffraction theory. Structural models have been found that enable the c orrelation functions to be calculated for various types of randomly pl aced defects (mosaic blocks and random elastic deformation). The appli cability of the method has been demonstrated by measuring the diffuse X-ray scattering from a ZnTe layer grown on a GaAs substrate. The para meters characterizing the defects were obtained from a comparison of t he calculated correlation function with theoretical models.