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. 02, 2004
Filed:
Jul. 01, 2002
Applicant:
Inventor:
Marc David Levenson, Saratoga, CA (US);
Assignee:
Other;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03F 9/00 ; G03C 5/00 ;
U.S. Cl.
CPC ...
G03F 9/00 ; G03C 5/00 ;
Abstract
A photolithography method and apparatus for producing minima of light intensity corresponding to a point in a phase shift mask is described. The phase shift in the light produced by the mask varies in a spiral fashion around the point so that the phase shift measured along lines drawn across the surface of the mask which pass through the point have a 180° jump at the point, and lines passing around the point have no jumps between 130° and 230°, and most preferably no jumps between 100° and 260°.