Estimation of Surface and Interface Roughness Using X-ray Reflectivity and TEM Observation

摘要

Surface and interface roughness of multilayer surface are often estimated with using X-ray reflectivity (XRR). In the conventional XRR analysis, the reflectivity is calculated based on the Parratt formalism, accounting for the effect of roughness by the theory of Nevot-Croce. However, the calculated result showed a strange phenomenon. The strange result had its origin in a currently used an equation due to serious mistake in which the Fresnel transmission coefficient in the reflectivity equation was increased at a rough interface because of a lack of consideration of diffuse scattering. Then we have developed a new improved formalism that corrects this mistake. In this study, we present the applying of the new improved formalism with the use of TEM observation results. The new improved formalism derives a more accurate analysis of the x-ray reflectivity from a multilayer surface of thin film material.