Atomic separation in Co/Cu/Co magnetic structures study by hybrid X-ray reflectivity – X-ray standing wave approach

The detailed characterization of nanometer-thin film structures is key to the in-depth understanding and property control of such objects. Here we present the analysis of Co/Cu/Co multilayer grown on and covered by thin Ta layers at individual layer thicknesses below 5 nm. The prime focus of the analysis was to detect the threshold Cu thickness required to separate effectively the magnetic Co layer. We found that a 4 nm Cu layer can effectively separate Co layers, but that 2.8 nm of Cu is not sufficient. To solve such structural characterization tasks, we adapted a hybrid X-ray reflectivity – X-ray standing wave free-form analysis technique. We applied that to the study of the Co layers separation by Cu and now it can be used to perform any task of this kind and also for other material combinations.