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:
Jan. 11, 2022
Filed:
Dec. 09, 2019
Applicant:
Ngk Insulators, Ltd., Nagoya, JP;
Inventors:
Assignee:
NGK Insulators, Ltd., Nagoya, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H02N 13/00 (2006.01); H01L 21/683 (2006.01); B23Q 3/152 (2006.01);
U.S. Cl.
CPC ...
H02N 13/00 (2013.01); B23Q 3/152 (2013.01); H01L 21/6833 (2013.01);
Abstract
An electrostatic chuck has a structure in which an electrostatic electrode is embedded in a disk-like ceramic plate and attracts a wafer that is placed on the ceramic plate and that has a diameter smaller than that of the ceramic plate by Johnsen-Rahbek force. The electrostatic chuck includes an insulating film that has an electric resistance larger than that of the ceramic plate in an annular region of a front surface of the ceramic plate from an outer circumferential edge of the ceramic plate to the inside of an outer circumferential edge of the wafer that is placed on the ceramic plate.