APPLICATIONS OF MULTIPLE-CRYSTAL DIFFRACTOMETRY

The elucidation of the structure of semiconductor multilayers can be a dequately determined by x-ray methods but the interpretation is not al ways straightforward. In this paper we introduce the idea of full thre e-dimensional diffraction-space mapping to obtain information on the t hree-dimensional structure of imperfect materials. We also stress the importance of this method for the interpretation of the data from high -resolution x-ray diffractometry. The presence of defects and diffract ion effects can create significant changes to the diffraction pattern that require a more complete analysis than that obtained from simple p rofiles. These subtle influences can in general only be understood by diffraction-space mapping. interpretation of diffraction-space maps fr om the high-resolution multiple-crystal multiple-reflection diffractom eter permits the use of three extra very powerful tools. The first is multiple-crystal topography so that the diffraction-space intensity fe atures can be related to lateral contrast on the photographic emulsion , the second is the accurate determination of lattice parameters and t he third is the simulation of the diffraction shapes using dynamical t heory.