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:
Oct. 19, 2004
Filed:
Oct. 19, 2001
George M. Clifford, Jr., Los Altos Hills, CA (US);
William Gong, Sunnyvale, CA (US);
Agilent Technologies, Inc., Palo Alto, CA (US);
Abstract
The invention provides a system and method for reliably and accurately measuring the gap between two materials when the depth of gap is less than the smallest distance that an optical thickness gauge (OTG) is able to measure. The invention is practiced by forming a suitable slot (or a groove, channel, hole or other suitable deformation) having a precisely known depth in at least one material. The sum of the distance of the gap and the depth of the slot is at least equal to the smallest distance that the OTG can measure. The slot is positioned over the materials and under the OTG probe head such that a cavity is formed. The depth of the cavity is measured. Since the distance of the slot is known, the depth of the gap is determined by subtracting the known depth of the slot from the measured depth of the cavity.