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. 02, 1999
Filed:
Feb. 14, 1997
Applicant:
Inventor:
William Yueh, Fullerton, CA (US);
Assignee:
Other;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B24B / ; B24B / ;
U.S. Cl.
CPC ...
451-5 ; 451-6 ; 451-7 ; 451290 ; 451285 ;
Abstract
Endpoint determination of a wafer removal process, in-situ, is afforded by the use of a Kalman filter known to be useful in celestial navigation. The use of line variable displacement transducers provides position error correction for the Kalman filter and the Preston equation provides the initial calibration for the endpoint determination. Accuracies of fifty angstrom are achieved.