The resolution function of triple-crystal X-ray diffractometer and its applications

Based on the dynamical theory of X-ray scattering, the resolution function of a triple-crystal X-ray diffractometer is studied with particular emphasis on high-resolution setups. A general form describing the intensity distribution of a Bragg peak in reciprocal space is derived. The dynamical streaks associated with a Bragg peak and the width of the resolution function under the Gaussian approximation are studied in detail. The theory of absolute integrated intensity measurement by means of a triple-crystal diffractometer is developed. X-ray diffraction with synchrotron sources and multi-reflection collimators are studied briefly.Most aspects of the theory are verified by experiments. Extensive measurements are conducted in vast 2$ theta$ range to test the width distribution of the resolution function. The streak structure in reciprocal space is also measured experimentally. The absolute integrated intensity measurements are conducted over a GaAs single crystal sample. All these results agree reasonably well with the theory.As an example of application, the atomic concentration difference of Ga and In atoms in Ga$ rm sb{0.5}In sb{0.5}$P superstructure is obtained through the absolute integrated intensity measurement, and the correlation length of the superstructure is estimated, with the help of Hendricks-Teller's model.X-ray reflectivity is a special case of a Bragg peak. By using X-ray reflectivity measurements, the interface and its subsequent evolution of Ti/Fe bilayer over SiO$ sb2$ substrate under various annealing stages are studied. The electron density profiles of the structures are acquired