CHARACTERIZATION OF MULTILAYERS BY X-RAY REFLECTION

The inclusion of refraction effects in kinematic scattering theory pro vides a powerful tool for describing diffuse scattering by X-ray refle ctivity. The theory is applied to multilayers with roughened interface s. Islands and miscut-induced steps as well as randomly oriented rough ness are included in the theory. The interfacial roughness leads to a broad, diffuse intensity distribution around the multilayer Bragg refl ections. From the line shape, the morphology of the interfaces can be deduced. The calculated profiles are compared with experimental data f rom a 4x(Si/GexSi1-x) multilayer with vicinal interfaces. Clear side p eaks are observed from which the mean island size and the average step height are deduced, which are consistent with AFM images. (C) 1998 El sevier Science B.V. All rights reserved.