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:
Apr. 11, 1995
Filed:
Apr. 16, 1992
Hitachi, Ltd., Tokyo, JP;
Abstract
The present invention enables the accuracy of aligning a wafer and a reticle with each other in the exposure step in the manufacture of a semiconductor integrated circuit device to be improved. The portions of a metal film 5 and a resist film 6 which cover an alignment mark 4 on a wafer 1 are removed by a gas assisted etching treatment using a laser beam prior to the execution of an exposure treatment, so as to bare the alignment mark 4. The position detecting light is then applied from an alignment mark position detecting means in a reduction projection exposure unit 11 to the alignment mark 4, the position of the alignment mark 4 being detected on the basis of the light reflected on and scattered from the alignment mark 4.