(538e) Exploring the Particle Augmented Mixed Lubrication (PAML) Modeling Approach

Slurry tribology involves analyzing the friction, lubrication, and/or wear behavior of particle-fluid mixtures which interact with surfaces. This problem has application to semiconductor wafer manufacturing where wafers are polished; solids processing, where surfaces are damaged due to shearing; and, fossil fuel productions where coal mixtures wear pipe walls. Predicting slurry tribology requires an understanding of multiple modes of mechanics, namely the fluid mechanics, particle mechanics, contact mechanics, and the mechanics of material wear. This work describes a new multi-physics, slurry tribology modeling framework called particle augmented mixed lubrication (PAML). In PAML, slurries often interact with surfaces in a way that leads to wear or material removal. Chemical mechanical polishing (CMP) is a semiconductor manufacturing process implemented in computer chip fabrication to achieve global planarization of wafers. During CMP, a slurry containing abrasive nanoparticles is used to remove material from the surface of the wafer. An excellent problem of slurry tribology, CMP will be used as a modeling test-bed for PAML. Consequently, the PAML computational model combines computational fluid dynamics (CFD), contact mechanics and discrete element modeling (DEM) to simulate CMP. In this study, PAML is used to predict the material removal rates of thin films during CMP.