INTERFACE ROUGHNESS IN SPUTTERED W/Si MULTILAYERS AND RELATED GROWTH MODELS T. Salditt, T.H. Metzger, D. Lott, J. Peisl, Sektion Physik der Universitaet Muenchen, D-80539 Muenchen, Germany

The interface morphology and roughness of sputtered multilayers changes dramatically when the Ar-pressure is raised above the threshold value, where the impinging atoms are thermalized by collisions in the gas phase. The corresponding changes in the height-height self- and cross- correlation functions have been studied by diffuse x-ray scattering, and are compared to simple statistical models of kinetic roughening. At low pressures very smooth interfaces are observed in agreement with the Edwards-Wilkinson Langevin equation, while at high pressures a columnar interface structure is found that evolves according to the Huygens-principle growth model of Tang, Alexander, and Bruinsma. The microscopic origins of this behavior are discussed along with a possible explanation for the absence of the Kardar- Parisi-Zhang type of growth.