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. 12, 1990
Filed:
May. 18, 1989
David K Studley, Sunnyvale, CA (US);
Ernest Keller, Sunnyvale, CA (US);
Genus, Inc., Mountain View, CA (US);
Abstract
A seal ring presses against a wafer on a CVD chuck continuously around the outer periphery of the wafer, and with sufficient force to hold the backside of the wafer against the chuck, so no CVD material may deposit on the backside of the wafer. The seal ring has one surface for contacting the frontside of the wafer and a second surface that extends close to the CVD chuck, so the edge of the wafer is also excluded from CVD coating. With use of the wafer seal ring apparatus and method, CVD coating is confined to the frontside of a wafer. In a preferred embodiment, an apparatus with a slide operated by a cam lever and a tension spring for moving the seal ring and pressing it against a wafer on a CVD chuck is used with each of multiple chucks attached to a rotatable turret within a CVD chamber.