Mechanisms for forming oxide layer over exposed polysilicon during a chemical mechanical polishing (cmp) process

Abstract

Embodiments of cleaning a surface of a polysilicon layer during a chemical mechanical polishing (CMP) process are provided. The method includes providing a substrate, and forming a gate structure on the substrate, and the gate structure includes a polysilicon layer. The method further includes forming an inter-layer dielectric layer (ILD) over the gate structure. The method also includes performing a CMP process to planarize the inter-layer dielectric layer (ILD) and to expose the polysilicon layer, and the CMP process includes: providing an oxidation solution to a surface of the substrate to perform an oxidation operation to form an oxide layer on the polysilicon layer; and providing a cleaning solution to the surface of the substrate to perform a cleaning operation.

Dependencies are inferred from the claim text.