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:
Sep. 15, 1992
Filed:
Sep. 17, 1991
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A mark detecting device usable in an alignment and exposure apparatus for aligning an alignment mark of a mask with an alignment mark of a wafer and for exposing a resist layer provided on the surface of the wafer to a pattern of the mask with radiation. The device includes a system for detecting light from the wafer, the detecting system including a photodetecting device for detecting light and a wavelength selecting element disposed in a path of light from the wafer to the photodetecting device so as to allow introduction of light of a predetermined wavelength into the light path from outside the light path to illuminate the wafer, and a portion for forming a photoprint of the alignment mark of the mask in the resist layer provided on the surface of the wafer, the photoprint forming portion being arranged, for the formation of the photoprint, to direct, to the wafer, the light of the predetermined wavelength from the outside of the light path and by way of the mask and the wavelength selecting element, wherein the photodetecting device is effective to detect the light from the wafer to detect the alignment mark of the wafer and the photoprint of the alignment mark of the mask.