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. 20, 2003
Filed:
Aug. 29, 2000
Applicant:
Inventor:
Joachim Schober, Graz, AT;
Assignee:
Koninklijke Philips Electronics N.V., Eindhoven, NL;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01B 1/114 ;
U.S. Cl.
CPC ...
G01B 1/114 ;
Abstract
A method and device is disclosed for determining deviations of a nominally planar surface of a thin object, which is subject to warpage related to gravity, such as a wafer, relative to a reference plane. The method includes supporting the object by three support members and detecting deviations, wherein the three support members are in a position relative to each other so that each support member is located underneath the point of gravity of a circular sector of the object extending over an angular range of 120°.