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:
Mar. 29, 1988
Filed:
May. 12, 1987
Kazuo Ushida, Tokyo, JP;
Satoru Anzai, Zama, JP;
Kazuaki Suzuki, Tokyo, JP;
Toshio Matsuura, Tokyo, JP;
Kyoichi Suwa, Yokohama, JP;
Koichi Matsumoto, Tokyo, JP;
Nippon Kogaku K. K., Tokyo, JP;
Abstract
An exposure method for photolithography comprises the steps of forming a pattern on a substrate by the use of a first exposure apparatus including a first imaging optical system having a reduction magnification 1/.beta.1 and an image circle of a diameter .phi.1, and forming a second pattern on the substrate on which the first pattern has been formed, by the use of a second exposure apparatus including a second imaging optical system having a reduction magnification 1/.beta.2 different from the reduction magnification 1/.beta.1 and an image circle of a diameter .phi.2, wherein when N is an integer, the conditions that .beta.1.times..phi.1=.beta.2.times..phi.2 and .phi.1=N.times..phi.2 are satisfied.