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, 2011
Filed:
Oct. 29, 2007
Nace Rossi, Singapore, SG;
Ranbir Singh, Singapore, SG;
Arun K. Nanda, Singapore, SG;
Agere Systems Inc., Allentown, PA (US);
Abstract
A shallow trench isolation structure having a negative taper angle and a method for forming same. A silicon nitride layer formed over a semiconductor substrate is etched according to a plasma etch process to form a first opening therein having sidewalls that present a negative taper angle. The substrate is etched to form a trench therein underlying the first opening. Silicon dioxide fills both the opening and the trench to form the shallow trench isolation structure, with the silicon dioxide in the opening exhibiting a negative taper angle to avoid formation of conductive stringers during subsequent process steps.