US5319245A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Local interconnect for integrated circuits
Assignee: STMicroelectronics lnc USA
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Filing: 1992-11-23
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Granted: 1994-06-07
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Expires: 2012-11-23
Abstract
Abstract A method for fabrication of local interconnects in an integrated circuit, and an integrated circuit formed according to the same, is disclosed. According to the disclosed embodiment, a first and a second conductive structure are formed over the integrated circuit. An insulating layer is formed over the integrated. A first photoresist layer is formed over the insulating layer, patterned and developed. The insulating layer is etched to expose selected regions of the first and second conductive structures. A refractory metal layer is formed over the integrated circuit. A barrier layer is formed over the refractory metal layer, and optionally a refractory metal silicide layer is formed over the barrier layer. A second photoresist layer is formed over the barrier layer, patterned and developed. The refractory metal layer and barrier layer, and the refractory metal silicide layer if formed, are etched to define a conductive interconnect between the exposed selected regions of the first and second conductive structures.
Inventors
- 👤 Fusen Chen
- 👤 Fu-Tai Liou
- 👤 Girish Dixit
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 12:40
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/40; H10W20/41; H10W20/44; H10W20/4403; H10W20/4437; H10W20/4441; H10W20/01; H10W20/031; H10W20/064; H10W20/066; H10W20/0698; Y; Y10; Y10S; Y10S148/00; Y10S148/019; Y10S257/00; Y10S257/915
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
86 words
An interconnect structure consisting of a portion of a semiconductor integrated circuit, comprising: a substrate; a first and a second conductive structure disposed over the integrated circuit and separated by an insulating layer; a first annealed refractory metal nitride layer disposed over a portion of the insulating layer, and contacting selected portions of the first and second conductive structures; a second deposited refractory metal nitride barrier layer disposed over the first annealed refractory metal layer; and a refractory metal silicide layer disposed over the barrier layer.
Claim 2
Dependent Claim
86 words
An interconnect structure consisting of a portion of a semiconductor integrated circuit, comprising: a substrate; a first and a second conductive structure disposed over the integrated circuit and separated by an insulating layer; a first annealed refractory metal nitride layer disposed over a portion of the insulating layer, and contacting selected portions of the first and second conductive structures; a second deposited refractory metal nitride barrier layer disposed over the first annealed refractory metal layer; and a refractory metal silicide layer disposed over the barrier layer.
Claim 3
Dependent Claim
13 words
The device of claim 1, wherein the refractory metal nitride comprises titanium nitride.
Claim 4
Dependent Claim
16 words
The device of claim 1, wherein the second deposited refractory metal nitride layer comprises titanium nitride.
Claim 5
Dependent Claim
14 words
The device of claim 1, wherein the refractory metal silicide layer comprises tantalum silicide.
Claim 6
Dependent Claim
15 words
The device of claim 1, wherein the first and second conductive structures comprise source/drain regions.
Claim 7
Dependent Claim
23 words
The device of claim 1, wherein the first conductive structure comprises a source/drain region and the second conductive structure comprises a gate electrode.
Claim 8
Dependent Claim
156 words
A conductive structure for an integrated circuit, comprising: first and second conductive structures disposed within the integrated circuit, and separated by an insulating region; a first interconnect layer lying on the insulating region and connecting the first and second conductive structures, such layer being formed from titanium nitride, and having physical properties resulting from formation by annealing a titanium layer in a nitrogen ambient to form the titanium nitride; a second interconnect layer lying on the first interconnect layer, such layer being formed from titanium nitride, and having physical properties resulting from formation by direct deposition of titanium nitride; refractory metal silicide regions within the first and second conductive structures where they are in contact with the refractory metal interconnect, wherein the refractory metal forming the silicide regions is the same material as the refractory metal in the refractory metal nitride interconnect; and a refractory metal silicide layer overlaying the second interconnect layer and coextensive therewith.
Claim 9
Dependent Claim
156 words
A conductive structure for an integrated circuit, comprising: first and second conductive structures disposed within the integrated circuit, and separated by an insulating region; a first interconnect layer lying on the insulating region and connecting the first and second conductive structures, such layer being formed from titanium nitride, and having physical properties resulting from formation by annealing a titanium layer in a nitrogen ambient to form the titanium nitride; a second interconnect layer lying on the first interconnect layer, such layer being formed from titanium nitride, and having physical properties resulting from formation by direct deposition of titanium nitride; refractory metal silicide regions within the first and second conductive structures where they are in contact with the refractory metal interconnect, wherein the refractory metal forming the silicide regions is the same material as the refractory metal in the refractory metal nitride interconnect; and a refractory metal silicide layer overlaying the second interconnect layer and coextensive therewith.
Claim 10
Dependent Claim
23 words
The conductive structure of claim 7, wherein the refractory metal interconnect comprises titanium nitride, whereby the refractory metal silicide regions comprise titanium silicide.
Claim 11
Dependent Claim
15 words
The conductive structure of claim 8, wherein the refractory metal silicide layer comprises tantalum silicide.
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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) | 1997-06-06 | 1997-12-06 | 1998-06-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-06-06 | 2001-12-06 | 2002-06-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-06-06 | 2005-12-06 | 2006-06-07 | $7700.00 | Window Closed / Lapsed |