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:
Jan. 31, 2012
Filed:
Dec. 24, 2009
Lily Jiang, Shanghai, CN;
Meng Feng Tsai, Shanghai, CN;
Jian Guang Chang, Shanghai, CN;
Abstract
A method for fabricating flash memory devices, e.g., NAND, NOR, is provided. The method includes providing a semiconductor substrate. The method includes forming a second polysilicon layer overlying a plurality of floating gate structures to cause formation of an upper surface provided on the second polysilicon layer. The upper surface has a first recessed region and a second recessed region. The method includes depositing a dielectric material overlying the upper surface to fill the first recessed region and the second recessed region to form a second upper surface region and cover a first elevated region, a second elevated region, and a third elevated region. The method subjects the second upper surface region to a chemical mechanical polishing process to remove the first elevated region, the second elevated region, and the third elevated region to cause formation of a substantially planarized second polysilicon layer free from the fill material.