A Chemical Mechanical Planarization Model Including Global Pressure Distribution and Feature Size Effects

Abstract

In this paper, we propose a chip-scale Chemical mechanical polishing (CMP) model based on the Greenwood–Williamson theory combining the effects of both the pad bulk deformation and the feature size, which are mainly responsible for global pressure distribution and feature-scale removal rate variation, respectively. A reference camber is first constructed to simulate the pad bulk deformation, which can be directly introduced into the global pressure distribution computation for incorporating the long-range characteristics of chip profiles. Then, both the effective curvature and the modified distribution function of pad asperity height are involved in the material removal rate. The model is first verified through some experimental data from CMP test structures and found to be in good agreement with the test data. For further validating the rationality and accuracy of the present model, some simulations are compared with our experimental data and discussed in detail.