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:
Mar. 26, 2002
Filed:
Nov. 02, 1999
Grant Kenji Larsen, Gloucester, MA (US);
Varian Semiconductor Equipment Associates, Inc., Gloucester, MA (US);
Abstract
Methods and apparatus are provided for holding a workpiece, such as a semiconductor wafer, during processing. The apparatus includes a platen assembly, a gas source and voltage source. The platen assembly includes a dielectric element that defines an electrically insulating clamping surface for receiving a workpiece and electrodes underlying the clamping surface. The electrodes include sealing electrodes at or near a periphery of the clamping surface. The gas source provides a gas in a region between the workpiece and the clamping surface for conducting thermal energy between the workpiece and the clamping surface. The voltage source applies sealing voltages to the sealing electrodes for producing an inwardly moving wave in the workpiece. Gas is transported inwardly away from the periphery of the clamping surface by the inwardly moving wave. The sealing electrodes may have the form of concentric rings at or near the periphery of the clamping surface.