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:
Aug. 28, 2001
Filed:
Jul. 10, 2000
Toshihiko Ishikawa, Mitaka, JP;
Yasushi Katagiri, Mitaka, JP;
Tokyo Seimitsu Co., Ltd., Tokyo, JP;
Abstract
A round groove is formed at the center of a wafer sucking face of a wafer suction pad. A plurality of annular grooves are formed on the wafer sucking face concentrically with the round groove. Each of the grooves is connected with an air intake line. Each of the air intake lines is connected with an air sucking device via a valve. Intake of the air is controlled by opening and closing of each of the valves. When holding the wafer by suction, the air is sucked only from the groove or grooves located inside the outer diameter of the held wafer. Therefore, the entire face of each of wafers of various sizes can be appropriately held by one wafer suction pad.