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:
May. 08, 2012
Filed:
Jan. 21, 2009
Applicants:
Christopher Vroman, Shrewsbury, MA (US);
Marshall Randolph, Wellesley, MA (US);
Inventors:
Christopher Vroman, Shrewsbury, MA (US);
Marshall Randolph, Wellesley, MA (US);
Assignee:
Entegris, Inc., Billerica, MA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B01D 53/22 (2006.01); B01D 39/20 (2006.01); B01D 46/10 (2006.01);
U.S. Cl.
CPC ...
Abstract
An apparatus and method for maintaining low gas velocity variation across a diffuser membrane during the vent-up of a vacuum chamber is disclosed. The diffuser membrane permeability and the pressure conditions across the membrane are chosen to minimize variation in gas flow velocity through the membrane during the vent-up cycle. This reduces re-distribution of particles from a vacuum chamber onto sensitive substrates in the vacuum chamber during vent-up from sub-atmospheric pressure to atmospheric pressure.