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:
Dec. 15, 2009
Filed:
Jul. 13, 2007
Applicant:
Gerald W. Gibson, Jr., Danbury, CT (US);
Inventor:
Gerald W. Gibson, Jr., Danbury, CT (US);
Assignee:
Agere Systems Inc., Allentown, PA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L 21/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
A process and apparatus for controlling an etchant gas concentration in an etch chamber. The etchant gas concentration and an inert gas concentration are determined and the latter concentration is used to normalize the etchant gas concentration. The normalized value is compared with a predetermined reference value and the flow of etchant gas into the chamber is controlled in response thereto.