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:
Apr. 09, 2002
Filed:
Sep. 27, 1999
Shinji Yamaguchi, Aichi, JP;
NGK Insulators, Ltd., Nagoya, JP;
Abstract
An electrostatic chuck includes a substrate, inner electrode and outer electrodes each made of a metal and concentrically buried in the substrate. A plurality of embossed portions are formed on a main plane of the substrate. A projecting portion is made of the same material as that of said plurality of the embossed portions and is formed on substantially an entire outer peripheral portion on the main plane of the substrate on which the embossed portions are formed. When positive and negative potentials are to be applied to the inner and outer electrode, respectively, or vice versa, an object to be treated is supported by the embossed portions and the projecting portion. A sum of a total area of upper surfaces of the embossed portions in an outer electrode-located zone of the substrate and an area of an upper surface of the projecting portion in the outer electrode-located zone of the substrate is in a range of 0.7 to 1.3 of a total area of upper surfaces of the embossed portions in an inner electrode-located zone of the substrate.