X-ray reflectivity of silicon on insulator wafers

The ability of X-ray reflectivity to analyse different silicon on insulator structures is underlined. The standard geometry with first reflection occu rring at the surface gives information about the thickness, roughness, and density of the layers. Deeply buried interfaces, i.e. in between thick wafe rs, are analysed with a non-standard geometry (the first reflection occurs at the buried interface) and with a high-energy radiation. These two method s are, respectively, illustrated by the reflectivity measurements of (SiO2/ Si/SiO2/bulk Si) and (bulk Si/thermal SiO2/native SiO2/bulk Si) bonded stru ctures, and are explained in the framework of kinematic theory of X-ray ref lectivity. (C) 2001 Elsevier Science Ltd. All rights reserved.