1Modeling of Pad-Wafer Contact Pressure Distribution in Chemical-Mechanical Polishing

Pressure distribution at a wafer-pad contact surface in chemical-mechanical polishing has been modeled using finite element analysis. The model reveals the pressure abrupt increment at the wafer peripheral portion resulting from geometrical discontinuity at the contact edge. The amplitude of the pressure abruptness varies significantly with properties of polishing pad. Furthermore, the effect of pressurized retainer ring on the pressure distribution has been analyzed, illustrating the fundamental functions of the retainer ring in improvement of the wafer-pad contact pressure distribution. 1