EP0224418A1
Expired / Lapsed
EP
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A programmable element for a semiconductor integrated circuit chip
Assignee: Fujitsu Ltd
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Filing: 1986-11-28
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Granted: —
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Expires: 2006-11-28
Abstract
Abstract A programmable element for a semiconductor integrated circuit device is formed from a couple of electrode layers(34,36) and an insulating layer (31) intervening therebetween and is programmed by applying a voltage between the electrode layers to cause an electrical breakdown and form a conduction path in the insulating layer. The insulting layer (31) comprises two films (32,33) of different dielectric materials, such as silicon nitride and silicon-dioxide successively formed on the lower electrode layer. Typically, the Si₃N₄ film has a thickness in the range between 5 and 20 nm and the SiO₂ film has a thickness in the range between 05 and 10 nm. The composite structure of the insulating layer results in a relatively low programming voltage and a reduced resistance of a programmed BIC cell.
Inventors
- 👤 Takahiro Nawata
- 👤 Kunihiko Pakusaido Musashikosugi 403 Wada
- 👤 Noriaki Sato
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 22:12
CPC Classifications
G; G11; G11C; G11C17/00; G11C17/04; H; H10; H10B; H10B20/00; H10B69/00; H10W; H10W20/00; H10W20/40; H10W20/49; H10W20/491
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
135 words
A programmable element for a semiconductor integrated circuit chip, comprising a lower electrode layer (34) formed on a substrate (35); a first insulating layer (31) formed on the lower electrode layer; and an upper electrode layer (36) formed on the first insulating layer, the upper electrode being separated from the lower electrode by the first insulating layer, whereby the programmable element is provided with a conduction path between the lower and upper electrodes when a voltage capable of causing an electrical breakdown in the first insulating layer is applied between the lower and upper electrodes, characterized in that said first insulating layer (31) is composed of at least two films (32,33) of dielectric materials, successively formed on said lower electrode layer (34), said dielectric material films having respective specific dielectric constants different from each other.
Claim 2
Dependent Claim
135 words
A programmable element for a semiconductor integrated circuit chip, comprising a lower electrode layer (34) formed on a substrate (35); a first insulating layer (31) formed on the lower electrode layer; and an upper electrode layer (36) formed on the first insulating layer, the upper electrode being separated from the lower electrode by the first insulating layer, whereby the programmable element is provided with a conduction path between the lower and upper electrodes when a voltage capable of causing an electrical breakdown in the first insulating layer is applied between the lower and upper electrodes, characterized in that said first insulating layer (31) is composed of at least two films (32,33) of dielectric materials, successively formed on said lower electrode layer (34), said dielectric material films having respective specific dielectric constants different from each other.
Claim 3
Dependent Claim
18 words
A programmable element according to claim 1, wherein one of said dielectric films is a silicon-nitride film (32).
Claim 4
Dependent Claim
23 words
A programmable element according to any one of claims 1 and 2, wherein one of said dielectric films is a silicon-dioxide film (33).
Claim 5
Dependent Claim
31 words
A programmable element according to any one of claims 1 to 3, wherein said first insulating layer comprises a relatively thin silicon-dioxide film (33) and a relatively thick silicon-nitride film (32).
Claim 6
Dependent Claim
32 words
A programmable element according to any one of the preceding claims, wherein one of said dielectric films is a silicon-nitride film (32) having a thickness in a range from 5nm to 20nm.
Claim 7
Dependent Claim
32 words
A programmable element according to any one of the preceding claims, wherein one of said dielectric films is a silicon-dioxide film (33) having a thickness in a range from 0.5nm to 10nm.
Claim 8
Dependent Claim
129 words
A programmable element according to any one of the preceding claims, wherein said substrate (35) is a semiconductor substrate having a conductivity type and said lower electrode (34) is an impurity diffusion layer formed in said semiconductor substrate, said impurity diffusion layer having a conductivity type opposite to that of said semiconductor substrate, and said programmable element further comprises a second insulating layer (37) formed on said semiconductor substrate, said second insulating layer having a contact hole selectively formed therein to expose said impurity diffusion layer (34), said first insulating layer (31) being formed on said contact hole so as to cover said exposed impurity diffusion layer and said conduction path is established between said impurity diffusion layer (34) and said upper electrode (36) by applying a voltage therebetween.
Claim 9
Dependent Claim
19 words
A programmable element according to claim 7, wherein said second insulating layer (37) is composed of a phospho-silicate glass.
Claim 10
Dependent Claim
33 words
A programmable element according to any one of claims 7 and 8, wherein said impurity diffusion layer (34) constitutes a drain region of a MIS FET (metal-insulator-semiconductor field-effect-transistor) formed in said semiconductor substrate.
Claim 11
Dependent Claim
52 words
A programmable element according to any one of the preceding claims, wherein said first insulating layer (31) includes a silicon-nitride film (32) and a silicon-dioxide film (33), said silicon-nitride film (32) having a thickness larger by a factor in the range from 1 to 40 than that of said silicon-dioxide film (33).
Claim 12
Dependent Claim
29 words
A programmable element according to any one of the preceding claims, wherein said first insulating layer (31) comprises an underlying silicon-nitride film (32) and an overlying silicon-dioxide film (33).
Claim 13
Dependent Claim
23 words
A programmable element according to claim 11, wherein said overlying silicon-dioxide film (33) is formed by partially oxidizing said underlying silicon-nitride layer (32).
Claim 14
Dependent Claim
27 words
A programmable element according to any one of claims 1 to 10, wherein said first insulating layer comprises an underlying silicon-dioxide film and an overlying silicon-nitride film.
Claim 15
Dependent Claim
25 words
A programmable element as set forth in claim 13, wherein said first insulating layer further comprises another silicon-oxide film formed on said overlying silicon-nitride film.
Claim 16
Dependent Claim
26 words
A programmable element as set forth in claim 14, wherein said another silicon-oxide film on said silicon-nitride film is formed by partially oxidizing said silicon-nitride film.
Claim 17
Dependent Claim
29 words
A programmable element according to any one of the preceding claims, wherein said upper electrode (36) is composed of a metal or metal alloy, including aluminium, molybdenum or platinum.
References Cited (Backward Citations)
US3576549A
Cited
US3793090A
Cited
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