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. 13, 1993
Filed:
Jan. 16, 1991
Yoshito Nakanishi, Kawasaki, JP;
Takeo Sato, Kawasaki, JP;
Nobuaki Furuya, Kawasaki, JP;
Takeo Miyata, Zama, JP;
Shinichi Mizuguchi, Osaka, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
An exposure system includes a pulse light source emitting light in response to a trigger signal and giving a predetermined exposure light quantity by a plurality of times of light emission. A reticle has an alignment mark and a light exposure pattern. A projection lens contractedly projects the pattern of the reticle. A wafer has an alignment mark to be located. The wafer is exposed to a projection of the pattern. A wafer stage is movable and carries the wafer. A laser interferometer measures a position of the wafer stage. An alignment device serves to detect a condition of an alignment of the wafer with respect to the reticle in an exposure position.