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. 31, 1988
Filed:
Oct. 29, 1985
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A wafer chuck for releasably holding a wafer, includes a base member having an upper surface for carrying and holding thereon the wafer, a lift mechanism operative on the wafer when it rests on the base member to move the wafer relative to the base member in a direction away from the base member, the lift mechanism having an operative member extending substantially in a direction to a radially inward position from a radially outward position of the base member, the operative member having an end portion movable, relative to the base member, between a first position at which it is retracted from the upper surface of the base member and a second position at which it is protrudent from the upper surface of the base member so as to engage with the wafer to move the same relative to the base member, and driving means for moving, relative to the base member, the end portion of the operative member between the first and second positions.