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:
Jun. 01, 2010
Filed:
Nov. 02, 2005
Arthur Keigler, Wellesley, MA (US);
Qunwei Wu, Westford, MA (US);
Zhenqiu Liu, Northboro, MA (US);
John Harrell, Paxton, MA (US);
Arthur Keigler, Wellesley, MA (US);
Qunwei Wu, Westford, MA (US);
Zhenqiu Liu, Northboro, MA (US);
John Harrell, Paxton, MA (US);
NEXX Systems, Inc., Billerica, MA (US);
Abstract
A method and apparatus for fluid sealing a workpiece retained by a workpiece holder are described. A pressure differential can be formed across a fluid seal to counteract fluid attempting to penetrate the fluid seal, which can contaminate the underside of the workpiece. The apparatus can include a ring forming a barrier to fluid entry with the workpiece and a source providing pressure to form the pressure differential. The pressure or the pressure differential can counteract hydroscopic fluid pressure or hydrostatic fluid pressure that is acting to force fluid through the barrier between the ring and the workpiece.