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. 29, 1988
Filed:
Jan. 11, 1988
Nobuyuki Akiyama, Yokohama, JP;
Asahiro Kuni, Tokyo, JP;
Yukio Kembo, Yokohama, JP;
Toshihiko Nakata, Yokohama, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An exposure apparatus comprises a stage; a base plate provided on the stage; a flexible chuck plate which is capable of sucking under vacuum a substantially entire surface of a substrate to a surface thereof; a plurality of vertical displacement generating mechanism including a plurality of feedscrews provided at the base plate with predetermined intervals therebetween, a plurality of rotational actuators for rotatively driving each of the feedscrews, and a plurality of spring members interposed between the chuck plate and the base plate so as to allow a tip of each of the feedscrews to be engaged with a rear surface of the chuck plate; restricting mechanism for restricting the chuck plate in such a manner as not to be displaced horizontally relative to the base plate; a mask holder for holding a mask; a mechanism for measuring a level of the mask held by the mask holder; and a mechanism for measuring a level of the substrate sucked onto the chuck plate, whereby each of the rotational actuators of the vertical displacement generating mechanism is driven on the basis of gaps between the mask and the substrated measured by the mechanism for measuring the level of the mask and the mechanism for measuring the level of the substrate so as to subject the substrate to deflection via the flexible chuck plate, thereby producing a uniform gap between the mask and the substrate.