Quantitative in situ x-ray diffraction analysis of magnetic multilayers during annealing

Abstract

In situ high-angle x-ray diffraction (XRD) measurements during an annealing process and extensive low- and high-angle XRD analysis before and after annealing have been performed to study the influence of annealing on the microstructure of a Ni81Fe19/Ag multilayer film. We concentrate on a detailed description and quantification of induced changes in microstructural properties and on changes in the crystalline structure of sublayers. The observed effects obtained from the high-angle XRD, where superlattice structural refinement and standard powder diffraction methods were used, are utilized to model the changes from microscopic point of view. The low-angle XRD reflectivity measurements were analyzed using a new distorted-wave Born approximation approach which enables to get information about interlayer structure parameters such as interface roughnesses, degree of vertical correlation and lateral correlation length. The presented low-angle and high-angle analysis demonstrates general applicability of x-ray diffraction for complex and quantitative in-situ investigation of structural changes in metallic multilayers during annealing. An effect of lateral scaling for different types of roughness is discussed and a general approach is shown for the case of metallic multilayers.