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:
Mar. 21, 2000
Filed:
Sep. 30, 1998
William A Enichen, Poughkeepsie, NY (US);
Christophe F Robinson, Hyde Park, NY (US);
Nikon Corporation, Tokyo, JP;
Abstract
Measurement marks are applied throughout the area of an e-beam projection mask on a grillage of struts extending between sub-field membrane mask areas concurrently with patterning the sub-field membrane mask areas. The thickness of the struts prevents printing of the measurement marks on the resist at the target plane even if inadvertently illuminated by the e-beam system. Measurement of the relative locations of the measurement marks after fabrication and incremental periods of use supports the development of compensation or correction in the electron-optical system for distortions of the mask which may be detected from the measurement marks by adjustment of operating parameters thereof.