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. 20, 2004
Filed:
Sep. 19, 2001
Thomas E. Grebs, Mountaintop, PA (US);
Joseph L. Cumbo, West Wyoming, PA (US);
Fairchild Semiconductor Corporation, South Portland, ME (US);
Abstract
A method for forming trenches in a device layer disposed on a silicon semiconductor substrate comprises: covering the device layer with an etch resistant masking layer to define at least two trench regions; removing semiconductor material from the exposed trench regions by applying an etching agent that selectively etches the semiconductor substrate with respect to the trench masking layer, thereby forming at least two trenches each comprising a floor and sidewalls; and, during the removal of semiconductor material, exposing the sidewalls to a passivating agent in increasing amounts, thereby passivating the sidewalls while reducing lateral etching of semiconductor material from them.