High planarizing method for use in a gate last process

摘要

A method for performing a chemical-mechanical polishing (CMP) is provided. The method includes processing a semiconductor substrate to form a dummy gate structure on the substrate, to form a hard mask on the dummy gate structure, and to form a contact etch stop layer (CESL) and an interlayer dielectric (ILD) layer on the hard mask, performing a first CMP process with a first slurry to modify a non-planar topography of the ILD layer, performing a second CMP process with a second slurry to remove the hard mask, and performing a third CMP process with a third slurry to remove an interfacial layer that forms between the dummy gate and hard mask during semiconductor processing.