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:
Jan. 18, 1994
Filed:
Nov. 15, 1991
Applicant:
Inventors:
Kazuya Kamon, Itami, JP;
Hitoshi Nagata, Itami, JP;
Assignee:
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G03F / ;
U.S. Cl.
CPC ...
430-5 ; 430 22 ; 430311 ; 430396 ;
Abstract
According to the inventive photomask, a light shielding pattern as well as a high reflection film are formed at one major surface side of a transparent substrate. Thus, a focal position in a resist film with respect to light directly passing through the high reflection film is separated from a focal position in the resist film with respect to light multiple-reflected by the high reflection film along the thickness direction of the resist film, whereby the depth of focus is enlarged as the result.