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. 17, 1990
Filed:
Dec. 28, 1988
Shuji Sugiyama, Mito, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A projection aligner having a projection optics which project circuit patterns of reticles on a wafer next by step, comprising an X-Y stage mounting the wafer and moved to an X or Y direction by a stage controller, a developer for developing an alignment mark projected on the wafer by the projection optics, an alignment mark detector being disposed on the projection optics, and a correcting arrangement for an offset error of the alignment mark detector by measuring the offset error of a zero point after the wafer is projected with an alignment mark by the projection optics, the alignment mark is developed by the developer and the developed alignment mark on the wafer is moved to is detection area which is previously set based on design data keeping the wafer fixed on the X-Y stage. The offset error is measured as moving distance of X-Y stage and adjust the stage controller or zero point of the alignment mark detector in order to project actual circuit patterns on the wafer correctly.