EVOLUTION OF SURFACE-MORPHOLOGY DURING GROWTH AND ION EROSION OF THIN-FILMS

A model is presented to describe the evolution of thin-film surface mo rphology during growth and ion erosion. Characteristic in-plane length scales and overall amplitude of the roughness are studied as a functi on of certain competing roughening and smoothing mechanisms. Particula r attention is paid to the deposition method of growth followed by ion erosion of an excess layer thickness. The model is extended to the ca se of multilayers, to include roughness correlations between different interfaces. Specular and diffuse x-ray-scattering measurements on Mo/ Si multilayers are interpreted in terms of the model. Quantitative agr eement between the model and the experimental data can be obtained if we assume viscous how to be the dominant smoothing mechanism during io n erosion of the Si layers.