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An in situ x-ray reflectivity study of the dynamic evolution of a growing interface was carried out for gold sputter-deposited onto a polished silicon substrate. X-ray reflectivity data were recorded during growth for thicknesses of the gold film ranging from 50 to 3500 A. A progressive kinetic roughening of the gold-vacuum interface was observed and the time-dependent interfacial width exhibits a power-law behavior. Aided by scanning-tunneling-microscopy measurements the scaling exponents were determined and compared with theoretical studies.

We have carried out x-ray reflectivity and adsorption measurements on thermally evaporated silver and gold films deposited onto substrates held at 80, 300, and 500 K to investigate whether the surfaces of such films are fractal in nature. Both techniques indicate self-affine fractal scaling for Ag films deposited at near-normal incidence onto substrates held at 80 K.

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We have employed a quartz crystal microbalance technique to study the thickness versus pressure dependence of a variety of thin (0 -5 nm) liquid films (water, cyclohexane, nitrogen, krypton, and xenon) adsorbed on metal surfaces. We observe the Lifshitz theory of van der Waals forces to provide an excellent description of nitrogen adsorption, and an inadequate description of water adsorption, with the remaining gases spanning the two extremes.

We studied the finite-size efFect on the first-order metal-insulator phase transition and the accompanying tetragonal-to-monoclinic structural transition of VO2 films. The VO2 films were epitaxially grown by a metal-organic chemical-vapor-deposition technique on the (101) growth plane of a 125-A-thick Ti02 buffer layer which was also epitaxially predeposited on polished sapphire (1120) substrates. The thickness of the VO2 films in this study ranges from 60 to 310 A. We find that VO2 films grow isomorphically on the Ti02 bufFer layer resulting in a high degree of epitaxial VO2 films.We determined structural correlation lengths of the VO2 films parallel and normal to the growth plane from the x-ray-diÃraction widths of VO2 reflections at room temperature.The structural order parameter associated with the monoclinic distortion and the change in resistivity associated with the metal-insulator phase transition were simultaneously measured using x-ray-diKraction and resistivity measurements. It was found that the transition temperature, width of the transition, and the estimated electronic gap are dependent on the structural correlation length normal to the growth plane. These dependences are discussed in terms of finite-size and substrate efFects on the first-order phase transition.