US5328868A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of forming metal connections
Assignee: International Business Machines Corp
•
Filing: 1992-12-10
•
Granted: 1994-07-12
•
Expires: 2012-12-10
Abstract
Abstract A metal connection for an integrated circuit device is effectively "cast" in place at any level of an integrated circuit. The "mold" for the connection is formed by depositing and patterning a sacrificial material, such as aluminum oxide or other metal oxides, and covering the sacrificial material with a protective material such as silicon dioxide or other insulators. After forming bore holes to the deposit of sacrificial material through the protective layer, the sacrificial material is removed by isotropic etching to form a cavity beneath and at least partially overlaid by the protective layer. Alternatively, a defect may be produced below the protective layer and filled with metal either with or without enlargement by further removal of material. This cavity is then filled with metal by deposition of the metal by, for instance, evaporation, sputtering and chemical vapor deposition or combinations thereof. Connections formed by this technique can be produced at any level of the integrated circuit and do not interfere with surface wiring. A plurality of such connections may be simultaneously formed at the same or different levels of the integrated circuit and the method may be repeated to form multi-level wiring patterns.
Inventors
- 👤 Richard A. Conti
- 👤 Kenneth DeVries
- 👤 James F. White
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:04
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/056; Y; Y10; Y10S; Y10S148/00; Y10S148/05; Y10S148/073
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
61 words
A method of forming a metal interconnection extending between at least two interconnection points including the steps of forming a cavity between a surface and a protective layer formed over said surface, and depositing metal in said cavity conforming to a portion of an interior surface of said cavity and extending through said cavity between said at least two interconnection points.
Claim 2
Independent Claim
61 words
A method of forming a metal interconnection extending between at least two interconnection points including the steps of forming a cavity between a surface and a protective layer formed over said surface, and depositing metal in said cavity conforming to a portion of an interior surface of said cavity and extending through said cavity between said at least two interconnection points.
Claim 3
Dependent Claim
25 words
A method as recited in claim 1, including the further step of forming an aperture from a surface of said protective layer to said cavity.
Claim 4
Dependent Claim
31 words
A method as recited in claim 1, wherein said protective layer is formed over a volume of sacrificial material and including the further step of removing said volume of sacrificial material.
Claim 5
Dependent Claim
39 words
A method as recited in claim 1, wherein said step of forming a cavity includes the steps of undercutting an edge of a layer of material, and depositing the protective layer over said undercut edge to form a void.
Claim 6
Dependent Claim
20 words
A method as recited in claim 4, including the further step of removing a sacrificial portion of said protective layer.
Claim 7
Dependent Claim
17 words
A method as recited in claim 3, wherein said volume of sacrificial material is a metal oxide.
Claim 8
Independent Claim
90 words
A method of forming a metal interconnection within an integrated circuit device including the steps of depositing a sacrificial material on a surface, depositing a protective layer over said sacrificial material, forming at least two bore openings from a surface of said protective layer to said sacrificial material, removing said sacrificial material to form a cavity overlaid by at least a portion of said protective layer, and depositing metal in said cavity, said metal deposited by said depositing step extending through said cavity between said at least two bore openings.
Claim 9
Independent Claim
90 words
A method of forming a metal interconnection within an integrated circuit device including the steps of depositing a sacrificial material on a surface, depositing a protective layer over said sacrificial material, forming at least two bore openings from a surface of said protective layer to said sacrificial material, removing said sacrificial material to form a cavity overlaid by at least a portion of said protective layer, and depositing metal in said cavity, said metal deposited by said depositing step extending through said cavity between said at least two bore openings.
Claim 10
Independent Claim
71 words
A method of forming a metal connection in a semiconductor electronic device having a layered structure, said method including the steps of forming a void in said layered structure of said electronic device, said void having a dimension extending between two locations in a layer of said layered structure, enlarging said void by simultaneously etching surfaces along the entirety of said dimension, and depositing metal throughout said dimension of said void.
Claim 11
Independent Claim
71 words
A method of forming a metal connection in a semiconductor electronic device having a layered structure, said method including the steps of forming a void in said layered structure of said electronic device, said void having a dimension extending between two locations in a layer of said layered structure, enlarging said void by simultaneously etching surfaces along the entirety of said dimension, and depositing metal throughout said dimension of said void.
References Cited (Backward Citations)
US4262399A
Cited
US4334348A
Cited
US4448797A
Cited
US4339305A
Cited
US4650696A
Cited
US4789648A
Cited
US4888300A
Cited
US4757033A
Cited
US4804560A
Cited
US4692994A
Cited
US4795722A
Cited
US4902533A
Cited
US4996133A
Cited
US4999314A
Cited
US5006478A
Cited
US5000818A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-07-11 | 1998-01-10 | 1998-07-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-07-11 | 2002-01-10 | 2002-07-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-07-11 | 2006-01-10 | 2006-07-12 | $7700.00 | Window Closed / Lapsed |