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:
Aug. 31, 1993
Filed:
Dec. 21, 1992
Kaoru Motonami, Hyogo, JP;
Masao Nagatomo, Hyogo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A semiconductor device includes a specific circuit portion having a predetermined function and a spare redundant circuit portion having the same function as the specific circuit portion. The semiconductor device includes a silicon substrate (1), an interlayer insulating film (2), an LT fuse (3), interconnection layers (4), a testing electrode (5) and a protection film (6). The interlayer insulating film (2) has a groove (11) and is formed on the silicon substrate (1). The LT fuse (3) is formed of polysilicon and is located immediately below the bottom wall of the groove (11). The interconnection layers (4) are formed on the interlayer insulating film (2) with the groove (11) therebetween. The testing electrode (5) is spaced from the interconnection layers (4) and is formed on the interlayer insulating film (2). The protection film (6) is formed on the interlayer insulating film to cover surfaces of the interconnection layers (4) and expose a surface of the testing electrode (5). A laser beam is irradiated to a bottom wall of the groove (11) to fuse and remove a part of the LT fuse (3). This substitutes the specific part having a defect with the redundant circuit portion. In this operation, neither the interconnection layers (4) is damaged, nor short-circuit and breakage thereof are caused.