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:
Sep. 28, 2004
Filed:
Mar. 25, 1999
Hoiman (Raymond) Hung, San Jose, CA (US);
Joseph P. Caulfield, Oakland, CA (US);
Hongqing Shan, San Jose, CA (US);
Michael Rice, Pleasanton, CA (US);
Kenneth S Collins, San Jose, CA (US);
Chunshi Cui, Santa Clara, CA (US);
Other;
Abstract
A plasma etching process, particularly useful for selectively etching oxide over a feature having a non-oxide composition, such as silicon nitride and especially when that feature has a corner that is prone to faceting during the oxide etch. A primary fluorine-containing gas, preferably hexafluorobutadiene (C F ), is combined with a significantly larger amount of the diluent gas xenon (Xe) enhance nitride selectivity without the occurrence of etch stop. The chemistry is also useful for etching oxides in which holes and corners have already been formed, for which the use of xenon also reduces faceting of the oxide. For this use, the relative amount of xenon need not be so high. The invention may be used with related heavy fluorocarbons and other fluorine-based etching gases.