US4270136A
Expired / Lapsed
US
⏱️ 0.0 years remaining
MIS Device having a metal and insulating layer containing at least one cation-trapping element
Assignee: Fujitsu Ltd
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Filing: 1979-03-23
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Granted: 1981-05-26
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Expires: 1999-03-23
Abstract
Abstract A metal layer of a metal-insulator-semiconductor type semiconductor device, e.g., a metal electrode on an oxide layer covering a semiconductor substrate of an MOS diode or an MOS FET, contains at least one cation-trapping element. The semiconductor substrate with the metal layer and the oxide layer is heated at an elevated temperature to diffuse some of the ions responsible for the cation-trapping element out of the metal layer and into the upper part of the oxide layer. The metal and oxide layers promote the surface passivation of the semiconductor device.
Inventors
- 👤 Nobuo Toyokura
- 👤 Hiroshi Tokunaga
- 👤 Shinichi Inoue
- 👤 Hajime Ishikawa
- 👤 Masaichi Shinoda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 13:04
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/60; H10D1/00; H10D1/60; H10D1/62; H10D1/66; H10D62/00; H10D62/80; H10D62/83; H10D64/00; H10D64/01; H10D64/013; H10D64/01302; H10D64/01332; H10D64/01336; H10D64/60; H10D64/62; H10D64/66; H10D64/665; H10D64/667; H10D64/68; H10P; H10P14/00; H10P14/40; H10P14/412; H10P95/00; H10D64/01346
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
81 words
A metal-insulator-semiconductor type semiconductor device comprising: a semiconductor substrate, an insulating layer convering a surface of said semiconductor substrate, a metal layer comprising at least one metal element selected from the group consisting of tungsten, molybdenum, titanium, tantalum, niobium, hafnium and iron formed on said insulating layer, and at least one cation-trapping element selected from the group consisting of boron, germanium, phosphorus, lead, tin, chromium and antimony comprised in said metal layer and in the upper part of said insulating layer.
Claim 2
Dependent Claim
81 words
A metal-insulator-semiconductor type semiconductor device comprising: a semiconductor substrate, an insulating layer convering a surface of said semiconductor substrate, a metal layer comprising at least one metal element selected from the group consisting of tungsten, molybdenum, titanium, tantalum, niobium, hafnium and iron formed on said insulating layer, and at least one cation-trapping element selected from the group consisting of boron, germanium, phosphorus, lead, tin, chromium and antimony comprised in said metal layer and in the upper part of said insulating layer.
Claim 3
Dependent Claim
34 words
A semiconductor device according to claim 1 or 13, the density of said cation-trapping element comprised in said metal layer being from 10 15 to 10 21 per cubic centimeter of said metal layer.
Claim 4
Dependent Claim
25 words
A semiconductor device according to claim 1, said device comprising a metal oxide semiconductor diode and said metal layer comprising an electrode of said device.
Claim 5
Dependent Claim
30 words
A semiconductor device according to claim 1, said device comprising a metal oxide semiconductor field effect transistor and said metal layer comprising at least a gate electrode of said device.
Claim 6
Dependent Claim
63 words
A metal-insulator-semiconductor type semiconductor device having a low density of contaminating impurity cations capable of producing instability in said device, said device comprising a semiconductor substrate, an insulating layer covering a surface of said semiconductor substrate, a metal layer on said insulating layer, and at least one cation-trapping element comprised in said metal layer and in the upper part of said insulating layer.
Claim 7
Dependent Claim
63 words
A metal-insulator-semiconductor type semiconductor device having a low density of contaminating impurity cations capable of producing instability in said device, said device comprising a semiconductor substrate, an insulating layer covering a surface of said semiconductor substrate, a metal layer on said insulating layer, and at least one cation-trapping element comprised in said metal layer and in the upper part of said insulating layer.
Claim 8
Dependent Claim
35 words
The device of claim 1 to 5, said contaminating impurity capable of producing instability comprising a minimum surface density in the range from 1×10 9 to 5×10 9 per square centimeter in said insulating layer.
References Cited (Backward Citations)
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US3617824A
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US3717798A
Cited
US3987480A
Cited
US4015175A
Cited
US4109372A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-05-25 | 1984-11-24 | 1985-05-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-05-25 | 1988-11-24 | 1989-05-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-05-25 | 1992-11-24 | 1993-05-26 | $7700.00 | Window Closed / Lapsed |