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:
Mar. 02, 2004
Filed:
Mar. 09, 1998
Bertrand Flietner, Hopewell Junction, NY (US);
Wolfgang Bergner, Wappingers Falls, NY (US);
Siemens Aktiengesellschaft, , DE;
Abstract
A method of forming a buried plate in a silicon substrate uses a silicon substrate having a deep trench etched into the silicon substrate. A highly doped polysilicon layer is formed within the trench. A nitride layer is then formed within the trench over the polysilicon layer. After forming both the polysilicon layer and the nitride layer, both the polysilicon layer and the nitride layer are etched from a certain uppermost portion of the sidewalls of the trench thereby exposing the silicon substrate at the uppermost portions of the sidewalls. After exposing the silicon substrate at the uppermost portions of the sidewalls, a collar oxide layer is formed over the exposed silicon substrate at the uppermost portions of the sidewalls thereby protecting any edges of the polysilicon layer exposed by the etching step.