Multiscale approaches for metal thin film growth

Abstract

Two recently developed multiscale approaches for simulations of metalization morphologies under ionized sputter deposition conditions are reviewed. These methods are capable of predicting the growth of thin films on the feature scale, based on calculations that are simultaneously carried out on all relevant scales and consistently employ data from atomistic simulations. In both techniques, the first step consists in molecular dynamics simulations that compute the relative probabilities of all relevant reactions taking place during physical vapor deposition. These probabilities are consequently employed in feature-scale simulators. One of the methods employs a two-dimensional cellular automaton technique to calculate the film topographies. The second approach employs a Green function method to combine the molecular dynamics results with a line of sight transport model in a two-dimensional feature, and incorporates all effects of re-emission and re-sputtering in a self-consistent manner. In the final step, a level-set method is used to describe the morphology of the growing film. Both methods provide complete growth rate models that allow the inclusion of energy and angular dependent reaction rates. Several applications of both techniques are discussed.