The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 24, 2013
Filed:
Sep. 23, 2011
LI Jiang, Shanghai, CN;
Mingqi LI, Shanghai, CN;
Abstract
A polishing method and a method for forming a gate are provided. The method includes forming a dummy gate on a semiconductor substrate including a sacrificial oxide layer and a polysilicon layer which covers the sacrificial oxide layer, forming spacers around the dummy gate, and successively forming a silicon nitride layer and a dielectric layer covering the silicon nitride layer. The method further includes polishing the dielectric layer until the silicon nitride layer is exposed, polishing the silicon nitride layer on a fixed abrasive pad until the polysilicon layer is exposed by using a polishing slurry with a PH value ranging from 10.5 to 11 and comprising an anionic surfactant or a zwitterionic surfactant. Additionally, the method includes forming an opening after removing the dummy gate, and forming a gate in the opening. The method eliminates potential erosion and dishing caused in the polishing of the silicon nitride layer.