Konotopskiy L. Grows features, structure and optical properties of Mg and Mg2Si based X-Ray mirrors

According to the results of the analysis of the coherent scattering pattern it was shown that the Mg layers at thicknesses less than 5.2 nm are discontinuous. An investigation of the thermal stability of the Zr/Mg MXM on a silicon substrate showed that they retain their structure in the initial state up to 450 °C. Further heating of the mirror leads to its destruction as a result of the interaction of magnesium and zirconium with the silicon substrate. The most heat-resistant X-ray mirrors that were studied in the work are the Si/Mg2Si MXMs. They retain high level of geometric perfection at temperatures up to 550 °C. An important feature of the Si/Mg2Si MXM is the growth of magnesium silicide layers in the amorphous state with Mg2Si crystalline inclusions in the metastable hexagonal modification. Annealing of the Si/Mg2Si MXM up to 400 °C is accompanied by a 3.5 % decrease in the period of the mirror as a result of crystallization of magnesium silicide in a denser hexagonal modification.