Modeling of evolution process of edge over erosion in copper CMP using frequency components algorithm

摘要

In this paper, the causes of edge over erosion (EOE) in copper CMP are investigated. Wafer patterns containing square-wave features with pattern density of 50% and line width of 0.18??m, 0.5??m, 1??m and 2??m are studied. Under same polishing condition, the evolution processes of edge over erosion of the four different pattern structures are simulated by using frequency components algorithm (linear system method). The wafer profiles of the four pattern structures during polishing processes are given. It is seen that the values of EOE, erosion and dishing are different with different line width of the pattern. The results of the simulation of EOE, erosion and dishing are compared with the experimental data. Conclusions are given.