Separation of diffuse scattering in specular X-ray reflectivity measurement

A research group led by Professor H. Zabel (Ruhr-Universität Bochum, Germany) has recently published an interesting paper discussing the solution to a well-known problem in X-ray reflectivity. The technique is for layered thin films, and can give the layer thickness, surface/interface roughness and correlations of the interface roughness parallel and perpendicular to the interface. Due to the finite size of the receiving detector slit, it will always collect not only pure specular reflection but also diffusely scattered radiation. For many years, the separation of the diffuse contribution to the intensity of specular reflection has been an important topic for reliable data analysis. The researchers propose several measurements using different slit openings for specular scans, and show some applications to realistic systems, such as periodic V/Fe multilayers prepared on MgO substrate, with V and Pd capping layers. For more information, see the paper, "Separation of the diffuse contribution to the specular x-ray scattering of multilayer films", V. P. Romanov et al., Phys. Rev. B 82, 165416 (2010).