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. 26, 2002
Filed:
Jul. 13, 1999
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
There is described a semiconductor device having a copper fuse which prevents damage to a silicon substrate beneath the copper fuse, which would otherwise be caused by a laser beam radiated to blow the copper fuse. A light absorbing layer is formed on the copper fuse layer from material whose light absorption coefficient is greater than that of a copper wiring layer. Light absorbed by the light absorbing layer is transmitted, through heat conduction, to the copper wiring layer beneath the light absorbing layer and further to a barrier metal layer beneath the copper wiring layer. Even when the widely-used conventional laser beam of infrared wavelength is used, the copper fuse can be blown. Since a guard layer is formed below the fuse layer, there can be prevented damage to the silicon substrate, which would otherwise be caused by exposure to the laser beam of visible wavelength. Therefore, the copper fuse can be blown even by use of a laser beam of visible wavelength whose light absorption coefficient for copper is high.