CHARACTERIZATION OF QUANTUM-WELLS BY X-RAY-DIFFRACTION

Measurements of the intensity distribution in diffraction space yield information far beyond that available by simple profiles. This paper briefly reviews the parameters obtainable from quantum well structures, when using conventional double-crystal and slit-based diffractometers, and shows how further structural parameters can be extracted by diffraction space mapping. To interpret subtle features a 'delta-function like' diffraction probe has been used to be sure of the origin of some of the features observed. The influence of layer tilting and lattice relaxation on the diffraction process can lead to imprecise fits, but from a diffraction space map, and including the diffuse scattering, further valuable information is extracted. The interpretation of these features has required additional modification to dynamical theory and the use of multiple-crystal topography. Examples of some unusual diffraction effects with possible explanations are also given.