Abstract: A novel mathematical model based on the force balance of wafer/particle/pad is developed for chemical mechanical polishing (CMP).The main feature of the model is the incorporation of the particle adhesion force and the large deformation of the particle and pad.The model shows that the adhesion force can significantly influence the load force of particles and the indentation depth of particles into Cu and SiO2 wafer surfaces.Furthermore,the model also predicts that the indentation depth of the particle into the wafer surface considering the adhesion force is two or four times than that of without an adhesion force.However,the magnitude of the indentation depth is on the order of molecular scale.The results and analysis reveal some insights into the molecular scale removal mechanism on the performance of the CMP.

Key words: chemical mechanical polishing, adhesion force, molecular-scale removal, modeling