US5925933A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Interconnect structure using Al2 -Cu for an integrated circuit chip
Assignee: International Business Machines Corp
•
Filing: 1996-10-11
•
Granted: 1999-07-20
•
Expires: 2016-10-11
Abstract
Abstract An interconnect structure and method for an integrated circuit chip for resisting electromigration is described incorporating patterned interconnect layers of Al or Al--Cu and interlayer contact regions or studs of Al 2 Cu between patterned interconnect layers. The invention overcomes the problem of electromigration at high current density in the interconnect structure by providing a continuous path for Cu and/or Al atoms to move in the interconnect structure.
Inventors
- 👤 Evan George Colgan
- 👤 Kenneth Parker Rodbell
- 👤 Paul Anthony Totta
- 👤 James Francis White
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 23:58
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/40; H10W20/41; H10W20/44; H10W20/4403; H10W20/4405; H10W20/4407; H10W20/42; Y; Y10; Y10S; Y10S438/00; Y10S438/927
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
169 words
An interconnect structure for an integrated circuit chip for resisting electromigration as high current densities pass through interlayer contact regions of said interconnect structure comprising: a first patterned interconnect layer including a first metal selected from the group consisting of copper, copper alloys, aluminum, and aluminum alloys, a first insulation layer over said first patterned interconnect layer, said first insulation layer having first electrical contact regions passing through said first insulation layer for making electrical contact with said first patterned interconnect layer, and a second patterned interconnect layer including a second metal selected from the group consisting of copper, copper alloys, aluminum and aluminum alloys over said first insulation layer and over said first electrical contact regions, said first electrical contact regions comprising contiguous grains of the compound Al 2 Cu in the theta phase throughout each of said first electrical contact regions thus allowing the transport of copper atoms and aluminum atoms due to very high current densities to and from said first and second patterned interconnect layers.
Claim 2
Dependent Claim
169 words
An interconnect structure for an integrated circuit chip for resisting electromigration as high current densities pass through interlayer contact regions of said interconnect structure comprising: a first patterned interconnect layer including a first metal selected from the group consisting of copper, copper alloys, aluminum, and aluminum alloys, a first insulation layer over said first patterned interconnect layer, said first insulation layer having first electrical contact regions passing through said first insulation layer for making electrical contact with said first patterned interconnect layer, and a second patterned interconnect layer including a second metal selected from the group consisting of copper, copper alloys, aluminum and aluminum alloys over said first insulation layer and over said first electrical contact regions, said first electrical contact regions comprising contiguous grains of the compound Al 2 Cu in the theta phase throughout each of said first electrical contact regions thus allowing the transport of copper atoms and aluminum atoms due to very high current densities to and from said first and second patterned interconnect layers.
Claim 3
Dependent Claim
21 words
An interconnect structure of claim 1 wherein said first patterned interconnect layer further includes a lower layer of TiAl 3 .
Claim 4
Dependent Claim
21 words
The interconnect structure of claim 1 wherein said first patterned interconnect layer further includes a top layer of TiAl 3 .
Claim 5
Dependent Claim
29 words
The interconnect structure of claim 1 wherein said first insulation layer includes a dielectric selected from the group consisting of silicon dioxide, silicon nitride, polyimide, and diamond like carbon.
Claim 6
Dependent Claim
21 words
The interconnect structure of claim 1 wherein said second patterned interconnect layer further includes a bottom layer of TiAl 3 .
Claim 7
Dependent Claim
39 words
The interconnect structure of claim 1 wherein said first electrical contact regions comprise substantially contiguous grains of the compound Al 2 Cu in the theta phase formed by annealing Cu in the range from 200° C. to 548° C.
Claim 8
Dependent Claim
43 words
The interconnect structure of claim 1 further including a second insulation layer over said second patterned interconnect layer and said first insulation layer, said second insulation layer having second electrical contact regions therein for making electrical contact with said second patterned interconnect layer.
Claim 9
Dependent Claim
53 words
The interconnect structure of claim 1 wherein said first patterned interconnect layer is selected from the group consisting of copper and copper alloys and further including a barrier layer to Cu atoms positioned between said first patterned interconnect layer and said first electrical contact regions to prevent said Al 2 Cu from decomposing.
Claim 10
Dependent Claim
94 words
The interconnect structure of claim 7 further including a third patterned interconnect layer including a third metal selected from the group consisting of copper, copper alloys, aluminum and aluminum alloys over said second insulation layer and over said second electrical contact regions, said second electrical contact regions comprising contiguous grains of the compound Al 2 Cu in the theta phase throughout each of said second electrical contact regions thus allowing the transport of copper atoms and aluminum atoms due to very high current densities to and from said second and third patterned interconnect layers.
Claim 11
Dependent Claim
39 words
The interconnect structure of claim 9 wherein said third electrical contact regions comprise substantially contiguous grains of the compound Al 2 Cu in the theta phase formed by annealing Cu in the range from 200° C. to 548° C.
References Cited (Backward Citations)
FR2143709A1
Cited
US4307179A
Cited
EP0045405A2
Cited
US4335506A
Cited
US4884123A
Cited
US5110759A
Cited
US5171642A
Cited
EP0395560A2
Cited
US5071714A
Cited
US5010039A
Cited
US5243221A
Cited
JPH04111317A
Cited
US5130274A
Cited
US5300307A
Cited
US5455195A
Cited
US5565707A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-07-19 | 2003-01-18 | 2003-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-07-19 | 2007-01-18 | 2007-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-07-19 | 2011-01-18 | 2011-07-20 | $7700.00 | Window Closed / Lapsed |