Beschreibung:
Optimization of Chemical Mechanical Planarization (CMP) on integrated circuits requires an accurate model of material removal. The current model of polishing is two-body abrasion of particles trapped at the asperity-substrate junction, however, this is not supported by friction measurements. A modified friction model is applied to data collected from a pin-on-disk experiment preformed on a fused silica wafer with various polymer polishing pads, flooded with a silica nanoparticle slurry. Results indicate that the friction arises predominantly in the swept region preceding the asperity contact. We will add to this measurements of the volume of the ware-track, indicating the rate of material removal. Our aim is to develop an Archard style relationship between friction and the material removal rate that is independent of the pad material. The long-term goal of this investigation is to aid in the optimization of CMP for structures of decreasing size.