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:
May. 05, 1998
Filed:
Dec. 06, 1996
Michael Stuart Gordon, Somers, NY (US);
Paul F Petric, Brewster, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method for improving the alignment of an electron-beam through the optical axis of lenses in a lithographic system is described. The beam is nominally tilted through the center of the lens, and by using a plurality of deflectors the beam is pivoted through the center of the lens using a square wave toggle. The resolution of the beam is measured as it scans over a target, for both toggle states. The nominal tilt angle is chosen such that the resolution is identical for both toggle states. This technique does not rely on using an observation station, as it is common on TEMs, to view a magnified image of the specimen. Therefore, this technique can be used to align a beam that has been shifted off the optical axis, for instance, in a Variable-Axis-Lens lithography (VAL) system.