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:
Apr. 11, 2017
Filed:
Dec. 10, 2013
Lam Research Corporation, Fremont, CA (US);
Richard Abraham, Sherwood, OR (US);
Robert Rash, Portland, OR (US);
David W. Porter, Sherwood, OR (US);
Steven T. Mayer, Lake Oswego, OR (US);
John Ostrowski, Lake Oswego, OR (US);
Lam Research Corporation, Fremont, CA (US);
Abstract
The embodiments disclosed herein relate to methods and apparatus for promoting bubble-free circulation of processing fluids in a recirculation system. Certain disclosed techniques involve passive, mechanical valve designs that promote variable resistance to flow in a drain. Other techniques involve automated flow control schemes that utilize feedback from flow meters, level sensors, etc. to achieve a balanced and bubble-free flow. The disclosed embodiments greatly reduce the incorporation of gas into a processing fluid, in particular as the processing fluid returns from a processing cell to a reservoir.