X-ray Diagnostics of Multilayer Ti/Ni Mirrors with Different Configurations of Si Buffer Layer Using X-ray Reflectometry and X-ray Standing Wave Methods

The results of studying the multilayer mirrors (periodic Ti/Ni structures with different configurations of Si buffer layer), which are promising in developing mirror optics for synchrotron radiation, are presented. Samples with period structures Ti/Ni, Ti/Si/Ni, Ti/Ni/Si, and Ti/Si/Ni/Si were investigated by X-ray reflectometry and X-ray standing wave (XSW) methods. It is found that the Ti/Ni system is characterized by the largest thicknesses of transition layers at the Ti/Ni interfaces. Addition of Si interlayers between Ti and Ni layers leads to a decrease in the transition layer thicknesses, while addition of Si only within a period or only between periods leads to asymmetry of electron density profiles and elemental distribution profiles over the structure depth. It is shown that the structure with a Si buffer layer both between layers within a period and between the periods themselves (Ti/Si/Ni/Si) is an optimal mirror configuration in terms of reflectometry intensity.