UC San Diego

In light of the development of third-generation synchrotron sources which deliver extremely bright radiation beam over a board energy band, tremendous progress has been made in x-ray science and the diverse range of disciplines that can be studied with x-ray. The special properties of synchrotron-produced x-ray such as coherence, polarization, etc., combined with different extreme experimental conditions, can meet almost any requirement of the research for material characterization, imaging, molecular dynamics, surface/interface physics and so on. In this work we will demonstrate how outstanding properties of synchrotron x-ray can be use to study the structural and dynamic properties of rapidly evolving nano -scale interfacial systems. A large part of this thesis is devoted to the investigation of the surface capillary fluctuations of laterally confined supported polystyrene films using x-ray photon correlation spectroscopy (XPCS), a young coherent scattering technique that can probes the dynamics of matter. The structural evolution of interfacial/surface system, such as the self-assembled nanoparticle film at water-air interface and the nano- imprinted polystyrene pattern, can be studied by different time-resolved x-ray small angle scattering techniques in grazing incidence geometry (GISAXS,GIXOS,GID), as well as the conventional specular reflectivity (XR) measurement. Particularly in the case of the liquid surface research, special efforts have been made to improve a recently developed diffuse scattering technique Grazing incidence off-specular x-ray scattering (GIXOS) for probing the structure at liquid interface with much better temporal resolution compared with that of XR. In this work We will present all the experimental results together with conclusive data analysis from the studies of these evolving systems with x-ray scattering techniques. In comparison to the reciprocal space studies with x-ray scattering tools, part of this thesis is devoted to the experiments using real space probes such as optical microscope and Atomic force microscope (AFM)