Abstract
This thesis work is divided into two parts :The first part is a study on the lattice-parameter variation of the crystals used for X-ray resonators. An X-ray resonator that was prepared from a four-inch Si (001) crystal wafer by using the microelectronic lithography is composed of two crystal plates as reflecting mirrors. Multiple reflections take place within the crystal gap and generate forward-transmitted and back-reflected beams. The coherent interaction among the transmitted and the reflected beams inside the crystal plates and within the gap leads to cavity resonance. During the crystal etching processes, the lattice-parameter might be different from that of the original perfect crystal. By employing high-resolution backscattering from (12 4 0), we have measured the lattice-parameter variation of the silicon crystals in the range from 0.42 p.p.m. to 2 p.p.m.The second part is the study on possible focusing effects in a coherent x-ray compound refractive lenses, CRL. In order to see the possibility of improving x-ray beam conditioners for producing a coherent and extremely parallel x-ray source for advanced high-resolution experiments, the multi-plate crystal cavities consisting of compound refractive lenses are employed. We have also simulated the situation that the incident beam is compressed during the process of passing through the CRL to understand its physics mechanism.