Study of Surface Charge Effects on Oxide and Nitride Planarization Using Alumina/Ceria Mixed Abrasive Slurries

摘要

The effect of surface charges on oxide and nitride film polishing was investigated using alumina/ceria mixed abrasive slurries. It was found that the surface charges on both the abrasives and the oxide and nitride blanket films being polished play a significant role in determining the polish rates. The polish rates increase when the surface films being polished and the abrasives are oppositely charged and decrease when they have the same charge. It was also established that the oxideitride film polish rates are higher with increasing hardness of the core alumina particles in the mixed slurry.