Physical Model for the Small-Scale Residual Topography in Chemical Mechanical Polishing ABSTRACT:In previous work, the small-scale topography evolution of the wafer surface was investigated for a typical interlevel dielectric chemical mechanical planarization process by means of a Fourier analysis of surface profiler scans. It was found that the amplitudes of the individual frequency components decay exponentially at a rate that depends on the respective spatial frequency. In this paper, a physical model of these findings is proposed, based on a linearized approximation of the Greenwood-Williamson approach to describe the contact between the pad and the wafer surface. The frequency dependency of the decay rates is attributed to the visco-elastic properties of the pad material (polyurethane). This connection is consistent with dielectric susceptibility measurements that show that the observed frequency dependency stems from a visco-elastic beta-transition in polyurethane. The resulting model not only describes the experimental data for a previous test pattern but also shows good agreement to measurements of a typical dynamic random access memory topography after chemical mechanical polishing. In addition, the current model reduces the systematic errors of the predicted topography as compared to the previous empirical model. Did you like this research project? To get this research project Guidelines, Training and Code... Click Here facebook twitter google+ linkedin stumble pinterest Nonlinear Sequential Bayesian Analysis-Based Decision Making for End-Point Detection of Chemical Mechanical Planarization (CMP) Processes Spectral Evidence of Si Complexes in HVPE-Grown GaAs