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:
Jul. 14, 1998
Filed:
Mar. 07, 1997
Ingo Pinnau, Palo Alto, CA (US);
Johannes G Wijmans, Menlo Park, CA (US);
Zhenjie He, Daly City, CA (US);
Shannon Goakey, San Jose, CA (US);
Richard W Baker, Palo Alto, CA (US);
Membrane Technology and Research, Inc., Menlo Park, CA (US);
Abstract
A process for separating perfluoro compound gas or vapor from another gas, typically nitrogen, in a gas mixture. The process involves a combination of membrane separation and condensation, and is particularly useful in the semiconductor industry, for treating exhaust gases from cleaning of chemical vapor deposition chambers. Operation of the condensation step at temperatures no lower than about -30.degree. C. reduces the need for refrigeration equipment and controls the amount of gas dissolved in the recovered perfluoro compound.