Process for polishing the top surface of a polysilicon gate
The process of polishing the top surface of a polysilicon gate electrode often results in significant loss of material before adequate smoothness is achieved. This problem is overcome in the present invention by laying down a thin layer of a dielectric on the surface of the polysilicon prior to the application of CMP. This provides a sacrificial layer that facilitates the polishing operation and results in a polysilicon surface that is both very smooth and achievable with minimum loss of polysilicon.
Taiwan Semiconductor Manufacturing Company
H H
H01L H01L
inventional inventional
Chen-Hua Syun-Ming Chung-Long
Yu Jang Chang