EP0025347A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Semiconductor devices having fuses
Assignee: Fujitsu Ltd
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Filing: 1980-09-04
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Granted: —
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Expires: 2000-09-04
Abstract
Abstract A semiconductor device has fuses (4) coated with protecting layer (5,7). The protecting layer (5,7) is selectively etched to open windows (8) so as to expose narrow centre portions of the fuses (4). After the opening of the windows, fusing operation of the fuses is carried out. A further insulating layer may then be applied, at least over the exposed centre portions of the fuses.The exposure of the centre portions of the fuses causes the fuses to blow more reliably and with wider gaps, for a given fuse-blowing current, than if the centre portions were coated with the protecting layer.
Inventors
- 👤 Hirohiko Mochizuki
- 👤 Masao Nakano
- 👤 Fumio Baba
- 👤 Tomio Nakano
- 👤 Yoshihiro Takemae
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 07:52
CPC Classifications
G; G11; G11C; G11C17/00; G11C17/14; G11C17/16; H; H10; H10W; H10W20/00; H10W20/40; H10W20/49; H10W20/493; H10W42/00; H10W42/80
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
32 words
A semiconductor device having fuses (4) coated with a protecting layer (5,7) characterized in that narrow centre portions of the fuses are exposed through a window formed in the said protecting layer.
Claim 2
Dependent Claim
32 words
A semiconductor device having fuses (4) coated with a protecting layer (5,7) characterized in that narrow centre portions of the fuses are exposed through a window formed in the said protecting layer.
Claim 3
Dependent Claim
15 words
A semiconductor device according to claim 1, wherein the device is a semiconductor memory device.
Claim 4
Dependent Claim
21 words
A semiconductor device according to claim 1 or 2, wherein each of the fuses has a bow-tie shape (4, Figure 3).
Claim 5
Dependent Claim
32 words
A semiconductor device according to claim 1, 2 or 3, wherein the protecting layer (5,7) is made of material selected from the group consisting of silicon dioxide, silicon nitride and phosphosilicate glass.
Claim 6
Dependent Claim
36 words
A semiconductor device according to any preceding claim, further comprising an additional protecting layer (10, Figure 4) which covers at least the exposed narrow centre portions of the fuses and is formed after a fuse-blowing operation.
Claim 7
Dependent Claim
29 words
A semiconductor device according to claim 5, wherein the additional protecting layer (10) is made of material selected from the group consisting of silicon nitride, phosphosilicate glass and polyimide.
References Cited (Backward Citations)
No citation records indexed.
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