A simulation approach of dishing in chemical mechanical polishing of inlaid copper structures

In this paper, an approach to simulate dishing in chemical mechanical polishing of inlaid copper structures is proposed. The simulation proposed in this study requires preliminary experiments to determine the material removal rate for both copper and silicon dioxide. With established material removal models, the instantaneous material removal rate at each location on the wafer can be estimated, thereby allowing the determination of the surface profile. The study of the effects of process parameters on dishing using the proposed approach shows good agreement with those found experimentally by other researchers. The effects of metal linewidth and down pressure were found to be more significant than the pad rigidity and pattern density. The verification test showed that the proposed approach was a vast improvement over previously established methods. (c) 2005 The Electrochemical Society. All rights reserved.