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. 30, 2000
Filed:
Feb. 04, 1998
Steven D Golladay, Hopewell Junction, NY (US);
Paul F Petric, Brewster, NY (US);
Hans C Pfeiffer, Ridgefield, CT (US);
Werner Stickel, Ridgefield, CT (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
Numerous largely unpredictable criticalities of operating parameters arise in electron beam projection lithography systems to maintain throughput comparable to optical projection lithography systems as minimum feature size is reduced below one-half micron and resolution requirements are increased. Using an electron beam projection lithography system having a high emittance electron source, variable axis lenses, curvilinear beam trajectory and constant reticle and/or target motion in a dual scanning mode wherein the target and/or wafer is constantly moved orthogonally to the direction of beam scan, high throughput is obtained consistent with 0.1 .mu.m feature size ground rules utilizing a column length of greater than 400 mm, a beam current of between about 4 and 35 .mu.A, a beam energy of between about 75 and 175 kV, a sub-field size between about 0.1 and 0.5 mm at the target at an optical reduction factor between about 3:1 and 5:1, a numerical aperture greater than 2 mrad and preferably between about 3 and 8 mrad and a scan length between about 20 mm and 55 mm. Reticle and target speed preferably differ by about the optical reduction factor.