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. 30, 1984
Filed:
Dec. 02, 1982
Masao Kosugi, Yokohama, JP;
Hiroshi Sato, Tokyo, JP;
Kazuo Takahashi, Tokyo, JP;
Ichiro Ishiyama, Kawasaki, JP;
Shuichi Yabu, Kawasaki, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
In a mask aligner, the actual element pattern of a mask is transferred onto a resist applied to the surface of a wafer, while the alignment pattern of the mask is not transferred onto said resist. That is, the line width of the alignment pattern of the mask is a line width which is not transferred to the wafer. If the pattern of the mask is formed so that the line width of the alignment pattern is thin as compared with that of the actual element pattern, the exposure amount in the alignment pattern portion on the resist applied to the surface of the wafer becomes excessive due to the diffraction phenomenon and thus, the alignment pattern of the mask is not transferred onto the wafer.