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:
Apr. 15, 2003
Filed:
Apr. 17, 2001
Cuong Duy Le, Gilroy, CA (US);
Other;
Abstract
A method for identifying metal layer thickness of an inspection sample according to one embodiment utilizes an eddy current probe to obtain initial resistance and reactance measurements from the inspection sample. Once these measurements have been obtained, the relative distance between the eddy current probe and inspection sample is increased and terminating resistance and reactance measurements are obtained. An inspection sample intersecting line may then be calculated using the initial and terminating resistance and reactance measurements. An intersecting point between a natural intercepting curve and the inspection sample intersecting line may also be determined. A reactance voltage of the intersecting point along a digital calibration curve is calculated to identify a closest two of a plurality of calibration samples. The metal layer thickness of the inspection sample may then be calculated by performing an interpolation between the identified closest two calibration samples.