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:
Jun. 14, 2016
Filed:
Aug. 09, 2007
Takumi Tandou, Asaka, JP;
Kenetsu Yokogawa, Tsurugashima, JP;
Masaru Izawa, Hino, JP;
HITACHI HIGH-TECHNOLOGIES CORPORATION, Tokyo, JP;
Abstract
The present invention provides a temperature control unit for an electrostatic adsorption electrode that is capable of controlling the wafer temperature rapidly over a wide temperature range without affecting in-plane uniformity while high heat input etching is conducted with high wafer bias power applied. A refrigerant flow path provided in the electrostatic adsorption electrode serves as an evaporator. The refrigerant flow path is connected to a compressor, a condenser, and a first expansion valve to form a direct expansion type refrigeration cycle. A second expansion valve is installed between the electrostatic adsorption electrode and the compressor to adjust the flow rate of a refrigerant. This makes it possible to compress the refrigerant in the refrigerant flow path of the electrostatic adsorption electrode and adjust the wafer temperature to a high level by raising the refrigerant evaporation temperature. Further, a thin-walled cylindrical refrigerant flow path is employed so that the thin-walled cylinder is deformed only slightly by the refrigerant pressure.