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Patent US5221449A successfully refreshed from Google Patents.
US5221449A
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Method of making Alpha-Ta thin films
Assignee: International Business Machines Corp
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Filing: 1992-07-09
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Granted: 1993-06-22
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Expires: 2012-07-09
Abstract
Abstract The present invention relates generally to a structure and a method of making Alpha-Ta films, and more particularly, to a structure and a method of making Alpha-Ta in thin films. A seed layer of Ta reactively sputtered in a nitrogen containing environment is grown on the substrate, and using this seed layer of Ta(N) layers of Alpha-Ta are then formed.
Inventors
- 👤 Evan G. Colgan
- 👤 Peter M. Fryer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:41
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/032; H10W20/042; H10W20/045; C; C23; C23C; C23C14/00; C23C14/06; C23C14/14; H10D; H10D30/00; H10D30/01; H10D30/021; H10D30/031; H10D30/0321; H10D64/00; H10D64/01; H10D64/013; H10D64/01302; H10D64/01304; H10D64/01316; H10P; H10P14/00; H10P14/40; H10P14/418
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
76 words
A method of making an alpha-Ta layer on a substrate the steps of: (a) forming a seed layer of tantalum doped with nitrogen (Ta(N)), reactively sputtered in a nitrogen containing ambient, on said substrate, wherein said seed layer has a thickness of at least 20 angstroms, and (b) depositing a layer of alpha-Ta on said Ta(N) seed layer in a nitrogen free ambient, wherein said layer of alpha-Ta has a resistivity of less than 50 micro-ohm-cm.
Claim 2
Independent Claim
76 words
A method of making an alpha-Ta layer on a substrate the steps of: (a) forming a seed layer of tantalum doped with nitrogen (Ta(N)), reactively sputtered in a nitrogen containing ambient, on said substrate, wherein said seed layer has a thickness of at least 20 angstroms, and (b) depositing a layer of alpha-Ta on said Ta(N) seed layer in a nitrogen free ambient, wherein said layer of alpha-Ta has a resistivity of less than 50 micro-ohm-cm.
Claim 3
Dependent Claim
18 words
The method of claim 1, wherein said seed layer of Ta(N) is between 20 and 500 angstroms thick.
Claim 4
Dependent Claim
18 words
The method of claim 1, wherein said seed layer of Ta(N) is between 20 and 40 angstroms thick.
Claim 5
Dependent Claim
19 words
The method of claim 1, wherein said seed layer of Ta(N) contains between 0.1 and 50.0 atomic percent nitrogen.
Claim 6
Dependent Claim
19 words
The method of claim 1, wherein said seed layer of Ta(N) contains between 1 and 35 atomic percent nitrogen.
Claim 7
Dependent Claim
20 words
The method of claim 1, wherein said alpha-Ta layer is deposited at temperatures of between 100° C. and 600° C.
Claim 8
Dependent Claim
20 words
The method of claim 1, wherein said alpha-Ta layer is deposited at temperatures of between 200° C. and 300° C.
Claim 9
Dependent Claim
21 words
The method of claim 1, wherein said alpha-Ta layer is deposited at temperatures of equal to or less than 200° C.
Claim 10
Dependent Claim
20 words
The method of claim 1, wherein the resistivity of said alpha-0Ta layer is equal to or less than 40 micro-ohm-cm.
Claim 11
Dependent Claim
25 words
The method of claim 1, wherein the total thickness of said Ta(N) seed layer and said alpha-Ta layer is between 100 angstroms and 4,000 angstroms.
Claim 12
Dependent Claim
25 words
The method of claim 1, wherein the total thickness of said Ta(N) seed layer and said alpha-Ta layer is between 500 angstroms and 2,000 angstroms.
Claim 13
Dependent Claim
19 words
The method of claim 1, wherein said seed layer of Ta(N) contains between 0.1 and 1.0 atomic percent nitrogen.
Claim 14
Dependent Claim
19 words
The method of claim 1, wherein said seed layer of Ta(N) contains between 0.1 and 35.0 atomic percent nitrogen.
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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) | 1996-06-21 | 1996-12-21 | 1997-06-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-06-21 | 2000-12-21 | 2001-06-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-06-21 | 2004-12-21 | 2005-06-22 | $7700.00 | Window Closed / Lapsed |