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:
Aug. 01, 2006
Filed:
Apr. 07, 2003
Dong-hoon Chung, Yongin, KR;
Jin-hyung Park, Seongnam, KR;
Dong-Hoon Chung, Yongin, KR;
Jin-Hyung Park, Seongnam, KR;
Samsung Electronics Co., Ltd., Suwon-si, KR;
Abstract
A chromeless photomask includes a main pattern portion and a complementary pattern portion formed in the surface of the transparent mask substrate adjacent to an outer peripheral edge of the main pattern portion. The main and complementary pattern portions are each formed by recessing a surface of a transparent mask substrate to produce respective protrusions and recesses that induce a phase difference of 180 degrees in light rays passing therethrough. The complementary pattern portion is designed to produce interference that prevents distortion in the photoresist pattern formed at a region by and corresponding to the edge of the main pattern portion of the photomask. Accordingly, the present invention provides for a relatively large secondary mask alignment margin.