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:
Oct. 19, 1993
Filed:
Oct. 16, 1991
Applicant:
Inventors:
Assignee:
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G03F / ;
U.S. Cl.
CPC ...
430-5 ; 430320 ;
Abstract
A method of manufacturing a photomask, according to the present invention, comprises the step of entirely forming an intermediate shifter on a transparent substrate, light shielding layers and a phase shifter such that the thickness of the intermediate shifter successively varies. In edge portion of the phase shifter, thus, the phase of light is continuosly shifted from 0 to 180 degree. As in result, light intensity at the edge portion does not decrease to zero but has a relatively large value, preventing a bridge to be formed.