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:
Aug. 26, 1997
Filed:
Aug. 15, 1995
Mohammed Anjum, Austin, TX (US);
Ibrahim K Burki, Austin, TX (US);
Craig W Christian, Buda, TX (US);
Advanced Micro Devices, Inc., Sunnyvale, CA (US);
Abstract
A field oxide is provided which purposefully takes advantage of fluorine mobility from an implanted impurity species. The field oxide can be enhanced or thickened according to the size (area and thickness) of the oxide. Fluorine from the impurity species provides for dislodgement of oxygen at silicon-oxygen bond sites, leading to oxygen recombination at the field oxide/substrate interface. Thickening of the oxide through recombination occurs after it is initially grown and implanted. Accordingly, initial thermal oxidation can be shortened to enhance throughput. The fluorine-enhanced thickening effect can therefore compensate for the shorter thermal oxidation time. Moreover, the thickened oxide regions are anistropically oxidized underneath existing thermally grown oxides and directly underneath openings between nitrides. The thickened oxides therefore do not cause additional shrinkage of the active areas which reside between field oxides.