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. 10, 1992
Filed:
Feb. 21, 1989
Susumu Komoriya, Tokorozawa, JP;
Takao Kawanabe, Tokorozawa, JP;
Shinya Nakagawa, Tachikawa, JP;
Takayoshi Oosakaya, Iruma, JP;
Nobuyuki Iriki, Kodaira, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
According to the present invention, in making alignment between a semiconductor integrated circuit wafer and a mask or a reticle in light exposure of the wafer with a monochromatic light such as g-, i- or h- line of a mercury lamp, using a reduced stepping exposure system, light from a predetermined pattern on the wafer is taken out to an off-axis position and observed according to a through-the-lens method; in this case as a characteristic feature of the invention, the observation light is taken out from below the reticle and is passed through chromatic aberration correcting lenses, thereby permitting the use of a polychromatic or continuous spectrum light.