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:
Sep. 06, 2005
Filed:
Mar. 04, 1999
Michael J. Penberth, Cambridgeshire, GB;
Graham S. Plows, Cambridgeshire, GB;
Adam Woolfe, Cambridgeshire, GB;
Michael J. Penberth, Cambridgeshire, GB;
Graham S. Plows, Cambridgeshire, GB;
Adam Woolfe, Cambridgeshire, GB;
DuPont Photomasks, Inc., Round Rock, TX (US);
Abstract
A method for calibrating the scan amplitude of an electron beam lithography instrument by determining the position of a feature within the scan. The method is effective at the operating frequency of the scan and using a limited bandwidth video signal including the steps of determining the reference feature to be an edge over which the video signal rises abruptly from a background level to a white level. The method turns the beam on only over a short region of the scan and represents the degree of overlap between the beam on portion of the scan and the white part of the feature as the total video signal accumulated in that scan.