Characterization of Surface Layer in Mo/Si Multilayer Using TotalElectron Yield and X-ray Reflectivity Techniques

In x-ray multilayer, the thickness of top layer plays an important role in determining its reflectivity performance. In experimentally grown multilayer, the top layer parameters are found significantly different from those of underneath layers due to growth related issues and contamination effect. The calculations suggest that for top layer characterization the sensitivity of reflectivity technique depends on layer material. Considering the top layer of silicon the first Bragg peak reflectivity of Mo/Si multilayer changes by 2-3% while change in top layer thickness by a factor of two and more, In case of SiO2 as a top layer material the 1st Bragg peak reflectivity changes by 13%. The analysis of total electron yield (TEY) data reveals that the technique can be used to probe 2-4 A variation in top layer thickness. The both technique-reflectivity and TEY, together gives an complete information of multilayer structural parameters.