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:
Dec. 15, 1998
Filed:
Mar. 20, 1997
Souji Koikari, Numazu, JP;
Shuichi Tamamushi, Kawasaki, JP;
Shusuke Yoshitake, Yokohama, JP;
Munehiro Ogasawara, Fujisawa, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
A charged particle beam lithograph apparatus of the present invention projects a charged particle beam onto a sample through a mask and lithographs a mask pattern on the sample through the movement of the charged particle beam. In order to focus the charged particle beam, the apparatus creates an electromagnetic field, from the magnetic lens, symmetric with respect to an optical axis of the charged particle beam. An aberration of the charged particle beam is created under the symmetric electromagnetic magnet. The aberration is compensated for under an electromagnetic field nonsymmetric with respect to the optical axis which is created by a deflection unit.