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:
Nov. 23, 1993
Filed:
Dec. 06, 1991
Peter Ebbing, Los Altos, CA (US);
Applied Materials, Inc., Santa Clara, CA (US);
Abstract
An inner lid is attached to a vacuum chamber, covering an inner region of the vacuum chamber. An outer lid, also attached to the vacuum chamber, covers the inner lid, leaving a region between the inner lid and the outer lid. A gas conduit allows gas to flow between the inner region of the vacuum chamber and the region between the inner lid and the outer lid. A filter is placed in or immediately outside the gas conduit to prevent particles from entering the inner region of the vacuum chamber from the region between the inner lid and the outer lid. Since the pressure is the same on the top and bottom of the inner lid, the inner lid does not flex and thus does not rub against the vacuum chamber when the vacuum chamber is pumped down or vented up.