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. 14, 2006
Filed:
Mar. 02, 2005
Joachim Junge, Burghausen, DE;
Robert Weiss, Winhoering, DE;
Joachim Junge, Burghausen, DE;
Robert Weiss, Winhoering, DE;
Siltronic AG, Munich, DE;
Abstract
A device for the simultaneous double-side grinding of workpiece wafers has two collinear grinding wheels and two hydropads oppositely positioned for hydrostatic bearing of the workpiece, each having at least one hydrostatic bearing and at least one dynamic pressure tube for measuring the spacing between the workpiece and the hydrdopads. The surfaces of the hydropads which face the workpiece are of nonplanar configuration, contoured in such a manner that the spacing between the surface and the workpiece adopts a minimum value near the edge of the hydropads proximate the grinding wheels, this spacing increasing at increasing distance from the grinding wheels. In a further embodiment, at least one bore, through which liquid and abraded material can be discharged from the vicinity of the dynamic pressure tube, is proximate each dynamic pressure tube.