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:
Feb. 22, 2022
Filed:
May. 08, 2019
Ulvac Techno, Ltd., Kanagawa, JP;
ULVAC TECHNO, LTD., Kanagawa, JP;
Abstract
The power supply apparatus for the electrostatic chuck of this invention has: DC power source units for applying DC voltage to electrodes of the electrostatic chuck; and an AC power source unit for causing AC current to flow through an electrostatic capacitance of the electrostatic chuck. Provided that: a circuit for charging an electrode, from DC power source unit, with chuck voltage in order to attract and hold in position the to-be-processed substrate with the electrostatic chuck, be defined as a first circuit and that; a circuit for clearing charges of the to-be-processed substrate be defined as a second circuit, the power supply apparatus further includes switching means for switching between the first circuit and the second circuit. The second circuit is provided with an AC power source unit and a voltmeter for measuring AC voltage.