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:
Dec. 20, 1994
Filed:
Apr. 25, 1994
Applicant:
Inventors:
Eiji Sakamoto, Sagamihara, JP;
Ryuichi Ebinuma, Machida, JP;
Shinichi Hara, Yokohama, JP;
Mitsuji Marumo, Sagamihara, JP;
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01J / ;
U.S. Cl.
CPC ...
25045311 ; 2504922 ; 279-3 ; 269 21 ;
Abstract
A wafer holding device of the vacuum attraction type includes a structural member having a protrusion for supporting a wafer and elastic members made of a material having an elasticity modulus smaller than that of the wafer and that of the structural member. The elastic members are distributed on a wafer attraction plane of the structural member.