Efficient modeling of thin film deposition for low sticking using a three-dimensional microstructural simulator

Modern deposition methods for the thin metal films used in very large scale integrated diffusion barriers take advantage of nonunity sticking effects to produce more uniform coatings. Modeling these processes at the feature scale can be challenging due to long execution times which arise from the need to solve self-consistently for the transport of material in the feature. This articlepresents a methodology for substantially decreasing the execution time for low sticking coefficient simulations. The method is a modification of the traditional sequential Monte Carlo technique in which there is a separation of the transport processes and deposition process. This allows for a normalization of the incident flux magnitude before deposition and a substantial improvement in execution time. The article presents the incorporation of this method into a three-dimensional microstructural simulator, 3D-FILMS. The simulator is first used to confirm the accuracy of the new methodology and then assess its improvement over the more traditional algorithm. Finally, simulations for chemical vapor-deposited W and for sputtered Ti deposition are presented. (C) 2001 American Vacuum Society.