X-ray reflectivity studies on polystyrene dead layers

Abstract

This thesis mainly focuses on the novel characters of the adsorbed layers formed at the solid substrate by using in-situ x-ray reflectivity. We characterized the thermal expansion as a function of temperature. We found the contraction of the adsorbed layer within the T-range from room temperature to 100, which is in contrast to the bulk behavior. We also found that the heterogeneous structure in the direction normal to the surface: the bulk-like top layer and high density bottom layer.