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:
Nov. 11, 2003
Filed:
Feb. 27, 2002
Applicant:
Inventors:
Yasuhisa Yamada, Tokyo, JP;
Kenichi Takada, Kanagawa, JP;
Assignee:
NEC Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G06F 1/750 ; G06F 1/900 ; G03F 9/00 ; G06K 9/03 ;
U.S. Cl.
CPC ...
G06F 1/750 ; G06F 1/900 ; G03F 9/00 ; G06K 9/03 ;
Abstract
A method for manufacturing a pair of complementary masks for use in an electron projection lithographic (EPL) technique uses an algorithm for distributing the design data to a pair of EPL masks. The algorithm allocates a positive sign or negative sign to each of the pattern data, summation of the areas of the pattern data having positive signs while subtracting the areas of the pattern data having negative signs, for obtaining a minimum of the sum. One or more of initial combination of the signs is prepared and the vicinity of the initial combination is calculated therefrom for obtaining an optimum combination.