Step Coverage, Uniformity and Composition Studies Using Integrated Vapour Transport and Film-Deposition Models

A Monte Carlo sputter flux transport model has been developed for efficient generation of angular, energy, and thickness uniformity distributions for application to integrated circuit metallization films. The model allows for arbitrary target erosion profiles and emission angular distributions and uses an energy-dependent gas-scattering model. Verification of the model using aluminum and copper pinhole images has been obtained. The resulting sputter distribution information can be input into a topography-level film-deposition model to provide step coverage and microstructure depictions. The combination of these two models has been used to examine metallization issues such as film thickness uniformity, step coverage, compositional variations in alloy films, and magnetron source design.