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. 15, 2005
Filed:
Sep. 24, 2002
Yi-nan Chen, Taipei, TW;
Tung-wang Huang, Taipei, TW;
Hsin-jung Ho, Shijr, TW;
Hsien-wen Liu, Tainan, TW;
Yi-Nan Chen, Taipei, TW;
Tung-Wang Huang, Taipei, TW;
Hsin-Jung Ho, Shijr, TW;
Hsien-Wen Liu, Tainan, TW;
Nanya Technology Corporation, Taoyuan, TW;
Abstract
A method of forming a bottle-shaped trench for capacitor in a semiconductor substrate. First, the semiconductor substrate is selectively etched to form a trench, wherein the trench has a top portion and a bottom portion. Then, an oxide film is formed on the top portion of the trench. Next, a rugged polysilicon layer is formed on the bottom portion and the top portion of the trench. The rugged polysilicon layer and the semiconductor substrate are etched through the bottom portion of the trench by diluted ammonia solution as the etchant to form a bottle-shaped trench having a rugged surface. Next, the oxide film is removed.