Combining non-specular X-ray scattering and X-ray absorption spectroscopy for the investigation of buried layers

We will present a new approach for the structural investigation of buried layers and interfaces by non-specular grazing incidence X-ray scattering. By measuring and evaluating the distinct off-specularly scattered intensities which appear for grazing angles in the vicinity of the critical angle of total reflection as a function of the X-ray photon energy in the vicinity of an X-ray absorption edge, the atomic short-range order around the X-ray absorbing atom within the surface or interface region is accessible. We will apply this new technique for the investigation of metallic bilayers consisting of about 25 nm Cu on top of 175 nm Au on a glass substrate, and show that the Cu-atoms at the Cu–air (vacuum)-interface can be separated from those at the inner Cu–Au interface in an unambiguous way.