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:
May. 15, 2001
Filed:
Jul. 23, 1999
Applicant:
Inventor:
Kuei-Wu Huang, Hsin-Chu, TW;
Assignee:
Taiwan Semiconductor Manufacturing Company, Hsin-Chu, TW;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L 2/1762 ;
U.S. Cl.
CPC ...
H01L 2/1762 ;
Abstract
A method is achieved for preventing oxide loss on the top corners of the isolation trenches and minimizing parasitic current leakage of the active devices on the substrate. The method consists of forming shallow trenches having either stepped or tapered walls in a silicon substrate using a pad oxide and silicon nitride mask. The dielectric material used to fill the trenches is then etched to form nitride spacers, which protect the top corners of the trench walls from subsequent etching but are removed prior to cleaning of the pad and forming of gate oxide around the trenches.