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. 08, 2003
Filed:
Dec. 01, 1998
Bo Su, San Jose, CA (US);
Applied Materials, Inc., Santa Clara, CA (US);
Abstract
A method for monitoring the focus-exposure settings of a stepper in a photolithography process is disclosed. A golden image of the target is stored in the CD-SEM. Then, during the FEM measurements, the target of each die is compared to the golden image, and a PR score is stored. Thus, a matrix, or a look-up table, is constructed which provides a PR score for each die with respect to the golden image. Then, during a line monitoring, when a target image is obtained it is compared to the golden image and a PR score is obtained. If the measured CD turns out to be out of bound, the PR score is checked against the PR matrix of the FEM to see the focus-exposure parameters that resulted in such a PR score. Such a matching would indicate the actual drift of the focus or exposure of the stepper.