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:
Jul. 01, 1997
Filed:
May. 15, 1995
Applicant:
Inventors:
Junji Miyazaki, Hyogo, JP;
Nobuyuki Yoshioka, Hyogo, JP;
Assignee:
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G03B / ; G03B / ; G03B / ;
U.S. Cl.
CPC ...
355 53 ; 355 71 ; 355 77 ;
Abstract
By the method of exposure using attenuation type phase shift mask, based on the phase angle of exposure light passing through second and third light transmitting portions and on hole diameters of the second and third light transmitting portions, an optimal value between first and second distances h.sub.1 and h.sub.2 can be calculated. Therefore, a resist film can be exposed at optimal focal position. As a result, even when there is a step in the material to be exposed, a desired pattern can be exposed with high precision through the same steps in every region of the material to be exposed.