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:
May. 19, 1998
Filed:
Jun. 28, 1990
Nobutaka Magome, Kanagawa-ken, JP;
Kazuya Ohta, Ohta-ku, Tokyo, JP;
Hiroki Tateno, Kanagawa-ken, JP;
Other;
Abstract
An error in alignment between both positions is obtained from reference position information incorporated in advance in an exposure apparatus for manufacturing a semiconductor and detection position information obtained by physically non-contact measuring a mark formed on an object to be measured such as a wafer, a mask or a wafer stage. This mark has a construction having a periodic pattern at a predetermined pitch in connection with a scanning direction. A periodic signal obtained by non-contact scanning the mark is subjected to Fourier integration processing and a phase angle including not only a fundamental wave component but a high-order component by calculation of a sine wave and a cosine component of Fourier conversion to thereby detect position information of an average center position of the mark with a correction of a mark deformation caused by wafer or process of mask added thereto. An error in alignment is corrected by relatively moving said object to a reference position.