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:
May. 29, 2001
Filed:
Jul. 30, 1999
Dennis B. Ames, Danbury, CT (US);
Michael J. Schade, Hopewell Junction, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A calibration wafer for precisely aligning a wafer-handling system that processes a plurality of product wafers. The calibration wafer has radial and thickness dimensions and tolerances equivalent to those of the product wafers and further comprises a first center marker adapted for alignment with a second center marker external to the calibration wafer. The calibration wafer may be a component of a wafer center alignment device for precisely aligning a wafer-handling system in a calibration location in relation to a wafer-processing tool, the device further comprising an alignment jig adapted to be repeatably mounted on the tool and on which the second center marker is located. The calibration wafer is adapted to be positioned so that the first center marker aligns with the second center marker. The first and second markers may be visual alignment devices, in which case the calibration wafer may be at least partially transparent, or the markers may be mechanical alignment devices or a transmitter and receiver. Methods for aligning a wafer-handling system are also provided.