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:
Aug. 16, 2005
Filed:
Jul. 28, 2003
Yi-nan Chen, Taipei, TW;
Hsin-chuan Tsai, Taoyuan, TW;
Yi-Nan Chen, Taipei, TW;
Hsin-Chuan Tsai, Taoyuan, TW;
Nanya Technology Corporation, Taoyuan, TW;
Abstract
A method for forming a bottle-shaped trench. A conductive layer surrounded by a doped layer is filled in a lower portion of a trench formed in a substrate. A doping region is formed in the substrate around the doped layer by a heat treatment. A collar silicon nitride layer is formed over an upper portion of the sidewall of the trench. The conductive layer and the doped layer are successively removed using the collar silicon nitride layer as a mask. The doping region is partially oxidized to form a doped oxide region thereon. The doped oxide region is removed to form a bottle-shaped trench. A conformable rugged polysilicon layer is formed in the lower portion of the bottle-shaped trench.