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. 18, 2025
Filed:
Jul. 18, 2022
Ngk Insulators, Ltd., Nagoya, JP;
NGK INSULATORS, LTD., Nagoya, JP;
Abstract
A wafer placement table includes a ceramic base, a first cooling base, and a second cooling base. The ceramic base has a wafer placement surface and incorporates a wafer attracting electrode and a heater electrode. The first cooling base is bonded via a metal bonding layer to a surface of the ceramic base on a side opposite to the wafer placement surface and has a first refrigerant flow channel capable of switching between supply and stop of supply of first refrigerant. The second cooling base is attached via a space layer, capable of supplying heat-transfer gas, to a surface of the first cooling base on a side opposite to the metal bonding layer and has a second refrigerant flow channel capable of switching between supply and stop of supply of second refrigerant.