Simulation and modeling of the structure and surface profile of sputtered refractory films for VLSI barriers

This thesis will present a new model for sputtered thin film growth of refractory metals based upon the atomic momentum of sputtered particles arriving at the substrate. The new model is incorporated into the original SIMBAD application to simulate certain phenomena of thin film growth that were previously not addressed.; Experimental metal films were sputtered on trenches/vias to a thickness of 1{dollar}mu{dollar}m. Tungsten was the primary metal used for most of the experiments. Analysis of metal films showed that lateral growth at the corners of the trenches/vias constantly exceeded simulation results obtained using previous SIMBAD models. The modified model takes into account motion of sputtered atoms due to their momentum after reaching the growing thin film surface. The new SIMBAD algorithm successfully produces thin films that closely depict experimental results including lateral growth features. A number of films were simulated using different conditions with the modified SIMBAD model to show the universality of the lateral growth phenomenon.