US5793112A
Expired / Lapsed
US
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Multilevel embedded wiring system
Assignee: Mitsubishi Electric Corp
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Filing: 1996-09-18
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Granted: 1998-08-11
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Expires: 2016-09-18
Abstract
Abstract The multilevel embedded wiring system for an IC has a capping layer on the conductive layer in channels or trenches in insulating layers. The capping layer prevents halation of light in a lithography process, resulting in a high precision structure. Even if Cu is used as the conductive material, the resulting wiring resistivity is still low and the diffusion and oxidation of Cu are prevented.
Inventors
- 👤 Makiko Hasegawa
- 👤 Yoshihiko Toyoda
- 👤 Takeshi Mori
- 👤 Tetsuo Fukada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:43
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/40; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/032; H10W20/033; H10W20/037; H10W20/034; H10W20/036; H10W20/40; H10W20/41; H10W20/425; H10W20/44; H10W20/4403; H10W20/4421; H10W20/4424
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
203 words
A multilevel embedded wiring system for an integrated circuit comprising: a substrate; a first insulating layer disposed on the substrate and including a first trench; a first electrically conductive material selected from the group consisting of Cu and Cu alloys and disposed in the first trench; a capping layer disposed in and filling the first trench, covering the first electrically conductive material, and selected from the group consisting of Ti, Ta, Mo, Cr, Al, W, alloys, oxides, and nitrides thereof, for preventing halation during exposure in a patterning process; a second insulating layer disposed on the first insulating layer and including a second trench generally aligned with the first trench; a second electrically conductive material disposed in and filling the second trench, selected from the group consisting of W, Cu, and Cu alloys, and contacting the capping layer; a third insulating layer disposed on the second insulating layer and having a third trench generally aligned with the second trench; a first barrier layer in the third trench and disposed on the second electrically conductive material; and a third electrically conductive material disposed on the first barrier layer and filling the third trench and selected from the group consisting of Cu and Cu alloys.
Claim 2
Dependent Claim
203 words
A multilevel embedded wiring system for an integrated circuit comprising: a substrate; a first insulating layer disposed on the substrate and including a first trench; a first electrically conductive material selected from the group consisting of Cu and Cu alloys and disposed in the first trench; a capping layer disposed in and filling the first trench, covering the first electrically conductive material, and selected from the group consisting of Ti, Ta, Mo, Cr, Al, W, alloys, oxides, and nitrides thereof, for preventing halation during exposure in a patterning process; a second insulating layer disposed on the first insulating layer and including a second trench generally aligned with the first trench; a second electrically conductive material disposed in and filling the second trench, selected from the group consisting of W, Cu, and Cu alloys, and contacting the capping layer; a third insulating layer disposed on the second insulating layer and having a third trench generally aligned with the second trench; a first barrier layer in the third trench and disposed on the second electrically conductive material; and a third electrically conductive material disposed on the first barrier layer and filling the third trench and selected from the group consisting of Cu and Cu alloys.
Claim 3
Dependent Claim
31 words
The multilevel embedded wiring system of claim 1 wherein the first and third electrically conductive materials are Cu, the second electrically conductive material is W, and the capping layer is TiWN.
Claim 4
Dependent Claim
31 words
The multilevel embedded wiring system of claim 1 wherein the first and third electrically conductive materials are AlSiCu, the second electrically conductive material is W, and the capping layer is TiWN.
Claim 5
Dependent Claim
15 words
The multilevel embedded wiring system of claim 1 wherein the first barrier layer is TiN.
Claim 6
Dependent Claim
38 words
The multilevel embedded wiring system of claim 1 wherein the capping layer has a part contacting a part of side walls of the trenches, thereby increasing contact area between the capping layer and the first electrically conductive material.
Claim 7
Dependent Claim
44 words
The multilevel embedded wiring system of claim 1 including a second barrier layer disposed on walls of the first, second, and third trenches in the first, second, and third insulating layers for preventing diffusion of Cu into the first, second, and third insulating layers.
Claim 8
Dependent Claim
15 words
The multilevel embedded wiring system of claim 6 wherein the second barrier layer is TiN.
Claim 9
Dependent Claim
17 words
The multilevel embedded wiring system of claim 6 wherein the first and second barrier layers are TiN.
Claim 10
Dependent Claim
285 words
A multilevel embedded wiring system for an integrated circuit comprising: a substrate; a first insulating layer disposed on the substrate and including a first trench; a first electrically conductive material selected from the group consisting of Cu and Cu alloys and disposed in the first trench; a first capping layer disposed in and filling the first trench, covering the first electrically conductive material, and selected from the group consisting of Ti, Ta, Mo, Cr, Al, W, alloys, oxides, and nitrides thereof, for preventing halation during exposure in a patterning process; a second insulating layer disposed on the first insulating layer and including a second trench generally aligned with the first trench; a second electrically conductive material disposed in and filling the second trench, selected from the group consisting of W, Cu, and Cu alloys, and contacting the first capping layer; a third insulating layer disposed on the second insulating layer and having a third trench generally aligned with the second trench; a first barrier layer in the third trench and disposed on the second electrically conductive material; a third electrically conductive material selected from the group consisting of Cu and Cu alloys and disposed in the third trench on the first barrier layer; a second capping layer disposed in the third trench, covering the third electrically conductive material, and selected from the group consisting of Ti, Ta, Mo, Cr, W, alloys, oxides, and nitrides thereof, for preventing halation during exposure in a patterning process; and a fourth insulating layer disposed on the third insulating layer and including a fourth trench generally aligned with the third trench and filled with a fourth electrically conductive material selected from the group consisting of W, Cu, and Cu alloys.
Claim 11
Dependent Claim
285 words
A multilevel embedded wiring system for an integrated circuit comprising: a substrate; a first insulating layer disposed on the substrate and including a first trench; a first electrically conductive material selected from the group consisting of Cu and Cu alloys and disposed in the first trench; a first capping layer disposed in and filling the first trench, covering the first electrically conductive material, and selected from the group consisting of Ti, Ta, Mo, Cr, Al, W, alloys, oxides, and nitrides thereof, for preventing halation during exposure in a patterning process; a second insulating layer disposed on the first insulating layer and including a second trench generally aligned with the first trench; a second electrically conductive material disposed in and filling the second trench, selected from the group consisting of W, Cu, and Cu alloys, and contacting the first capping layer; a third insulating layer disposed on the second insulating layer and having a third trench generally aligned with the second trench; a first barrier layer in the third trench and disposed on the second electrically conductive material; a third electrically conductive material selected from the group consisting of Cu and Cu alloys and disposed in the third trench on the first barrier layer; a second capping layer disposed in the third trench, covering the third electrically conductive material, and selected from the group consisting of Ti, Ta, Mo, Cr, W, alloys, oxides, and nitrides thereof, for preventing halation during exposure in a patterning process; and a fourth insulating layer disposed on the third insulating layer and including a fourth trench generally aligned with the third trench and filled with a fourth electrically conductive material selected from the group consisting of W, Cu, and Cu alloys.
Claim 12
Dependent Claim
36 words
The multilevel embedded wiring system of claim 9 wherein the first and third electrically conductive materials are Cu, the second and fourth electrically conductive materials are W, and the first and second capping layers are TiWN.
Claim 13
Dependent Claim
36 words
The multilevel embedded wiring system of claim 9 wherein the first and third electrically conductive material are AlSiCu, the second and fourth electrically conductive materials are W, and the first and second capping layers are TiWn.
Claim 14
Dependent Claim
26 words
The multilevel embedded wiring system of claim 9 further including a second barrier layer interposed between the second capping layer and the fourth electrically conductive material.
Claim 15
Dependent Claim
17 words
The multilevel embedded wiring system of claim 12 wherein the first and second barrier layers are TiN.
Claim 16
Dependent Claim
47 words
The multilevel embedded wiring system of claim 9 including a third barrier layer disposed on walls of the first, second, third, and fourth trenches in the first, second, third, and fourth insulating layers for preventing diffusion of Cu into the first, second, third, and fourth insulating layers.
Claim 17
Dependent Claim
18 words
The multilevel embedded wiring system of claim 14 wherein the first, second, and third barrier layers are TiN.
Claim 18
Dependent Claim
196 words
A multilevel embedded wiring system for an integrated circuit comprising: a substrate; a first insulating layer disposed on the substrate and including a first trench; a first electrically conductive material selected from the group consisting of Al and Al alloys and disposed in the first trench; a capping layer disposed in and filling the first trench, covering the first electrically conductive material, and selected from the group consisting of Ti, Ta, Mo, Cr, Al, W, alloys, oxides, and nitrides thereof, for preventing halation during exposure in a patterning process; a second insulating layer disposed on the first insulating layer and including a second trench generally aligned with the first trench; a second electrically conductive material disposed in and filling the second trench, consisting of W, and contacting the first capping layer; a third insulating layer disposed on the second insulating layer and having a third trench generally aligned with the second trench; a first barrier layer in the third trench and disposed on the second electrically conductive material; and a third electrically conductive material disposed on the first barrier layer and filling the third trench and selected from the group consisting of Al and Al alloys.
Claim 19
Dependent Claim
196 words
A multilevel embedded wiring system for an integrated circuit comprising: a substrate; a first insulating layer disposed on the substrate and including a first trench; a first electrically conductive material selected from the group consisting of Al and Al alloys and disposed in the first trench; a capping layer disposed in and filling the first trench, covering the first electrically conductive material, and selected from the group consisting of Ti, Ta, Mo, Cr, Al, W, alloys, oxides, and nitrides thereof, for preventing halation during exposure in a patterning process; a second insulating layer disposed on the first insulating layer and including a second trench generally aligned with the first trench; a second electrically conductive material disposed in and filling the second trench, consisting of W, and contacting the first capping layer; a third insulating layer disposed on the second insulating layer and having a third trench generally aligned with the second trench; a first barrier layer in the third trench and disposed on the second electrically conductive material; and a third electrically conductive material disposed on the first barrier layer and filling the third trench and selected from the group consisting of Al and Al alloys.
Claim 20
Dependent Claim
24 words
The multilevel embedded wiring system of claim 16 wherein the first and third electrically conductive materials are Al and the capping layer is TiWN.
Claim 21
Dependent Claim
24 words
The multilevel embedded wiring system of claim 16 wherein the first and third electrically conductive materials are AlSiCu and the capping layer is TiWN.
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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) | 2001-08-10 | 2002-02-09 | 2002-08-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-08-10 | 2006-02-09 | 2006-08-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-08-10 | 2010-02-09 | 2010-08-11 | $7700.00 | Window Closed / Lapsed |