Patent US4426369A successfully refreshed from Google Patents.
Patent FR607074A successfully refreshed from Google Patents.
US5654232A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Wetting layer sidewalls to promote copper reflow into grooves
Assignee: Intel Corp
•
Filing: 1996-03-15
•
Granted: 1997-08-05
•
Expires: 2016-03-15
Abstract
Abstract A manufacturable method for forming a highly reliable electrical interconnection. An electrical interconnection pattern is first formed in a dielectric layer on a semiconductor substrate as recessed regions in the dielectric layer. Sidewalls containing a material which wets copper are then formed against the walls within the recessed regions. A conductive layer primarily comprising copper is thereafter deposited over the surface and in the recessed regions of the dielectric layer. The conductive layer is then reflowed to fill the recessed regions of the dielectric layer with substantially no void formation.
Inventors
- 👤 Donald S. Gardner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 06:38
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/032; H10W20/033; H10W20/034; H10W20/056; H10W20/059; H10W20/071; H10W20/074; H10W20/076
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
119 words
A method of forming an electrical conductor over a semiconductor substrate, said method comprising the steps of: (a) forming a recessed region in a first layer above said semiconductor substrate; (b) forming sidewalls adjacent to each of two laterally opposing walls within said recessed region by conformally depositing a wetting layer within said recessed region and subsequently anisotropically etching said wetting layer, said wetting layer comprising a wetting material which wets copper; (c) forming a second layer above said first layer such that at least a portion of said second layer is formed in said recessed region, said second layer comprising pure copper or copper alloyed with a dilute quantity of other elements; and (d) reflowing said second layer.
Claim 2
Independent Claim
119 words
A method of forming an electrical conductor over a semiconductor substrate, said method comprising the steps of: (a) forming a recessed region in a first layer above said semiconductor substrate; (b) forming sidewalls adjacent to each of two laterally opposing walls within said recessed region by conformally depositing a wetting layer within said recessed region and subsequently anisotropically etching said wetting layer, said wetting layer comprising a wetting material which wets copper; (c) forming a second layer above said first layer such that at least a portion of said second layer is formed in said recessed region, said second layer comprising pure copper or copper alloyed with a dilute quantity of other elements; and (d) reflowing said second layer.
Claim 3
Dependent Claim
29 words
The method of claim 1 wherein at least a portion of said second layer is deposited by a method selected from the group consisting of sputtering, CVD, and evaporation.
Claim 4
Dependent Claim
29 words
The method of claim 2 wherein said second layer is formed and said reflow is performed under high vacuum to ultra high vacuum conditions within the same vacuum system.
Claim 5
Dependent Claim
21 words
The method of claim 2 wherein said reflow is performed at a temperature in the range of approximately 200° C.-800° C.
Claim 6
Dependent Claim
29 words
The method of claim 1 wherein said second layer is formed and said reflow is performed under high vacuum to ultra high vacuum conditions within the same vacuum system.
Claim 7
Dependent Claim
23 words
The method of claim 1 wherein said wetting material is selected from the group consisting of silicon nitride, Ta, and any combination thereof.
Claim 8
Dependent Claim
21 words
The method of claim 1 wherein said reflow is performed at a temperature in the range of approximately 200° C.-800° C.
Claim 9
Dependent Claim
37 words
The method of claim 1 further comprising the step of etching at least a portion of said second layer which exists outside said recessed region such that said second layer becomes substantially isolated within said recessed region.
Claim 10
Dependent Claim
40 words
The method of claim 1 wherein said second layer comprises a material selected from the group consisting essentially of pure copper, a vanadium alloy of copper, a niobium alloy of copper, a palladium alloy of copper, and any combination thereof.
Claim 11
Dependent Claim
33 words
The method of claim 1 wherein said second layer comprises pure copper to which elements are added in an amount of between approximately 0.01 to 2 atomic percent to form an alloy thereof.
Claim 12
Dependent Claim
51 words
The method of claim 1 wherein said recessed region is formed by a process including dry etching a dielectric region of said first layer, said dielectric region comprising a material selected from the group consisting essentially of oxide, nitride, silicon oxynitride, BSG, PSG, BPSG, silicon carbide, polyimide and any combination thereof.
Claim 13
Dependent Claim
28 words
The method of claim 1 wherein said second layer is deposited in an inert atmosphere and is maintained in said inert atmosphere until after said reflow is performed.
Claim 14
Independent Claim
148 words
A method of forming an electrical conductor over a semiconductor substrate, said method comprising the steps of: (a) forming a recessed region in a first layer over said semiconductor substrate, said first layer comprising a dielectric material; (b) forming sidewalls adjacent to each of two laterally opposing walls within said recessed region by conformally depositing a wetting layer within said recessed region and subsequently anisotropically etching said wetting layer, said wetting layer being capable of wetting copper; (c) sputtering a second layer above said first layer such that at least a portion of said second layer is deposited in said recessed region, said second layer comprising pure copper or copper alloyed with a dilute quantity, of other elements; and (d) reflowing said second layer by exposing said second layer to a temperature in the range of approximately 200° C.-800° C. under high vacuum to ultra high vacuum conditions.
Claim 15
Independent Claim
148 words
A method of forming an electrical conductor over a semiconductor substrate, said method comprising the steps of: (a) forming a recessed region in a first layer over said semiconductor substrate, said first layer comprising a dielectric material; (b) forming sidewalls adjacent to each of two laterally opposing walls within said recessed region by conformally depositing a wetting layer within said recessed region and subsequently anisotropically etching said wetting layer, said wetting layer being capable of wetting copper; (c) sputtering a second layer above said first layer such that at least a portion of said second layer is deposited in said recessed region, said second layer comprising pure copper or copper alloyed with a dilute quantity, of other elements; and (d) reflowing said second layer by exposing said second layer to a temperature in the range of approximately 200° C.-800° C. under high vacuum to ultra high vacuum conditions.
Claim 16
Dependent Claim
29 words
The method of claim 13 wherein at least a portion of said wetting layer is deposited by a method selected from the group consisting of CVD, PECVD, and nitridation.
Claim 17
Dependent Claim
22 words
The method of claim 14 wherein said wetting layer is formed to a thickness in the range of approximately 50 Å-400 Å.
Claim 18
Dependent Claim
38 words
The method of claim 14 further comprising the step of chemically-mechanically etching at least a portion of said second layer which exists outside said recessed region such that said second layer becomes substantially isolated within said recessed region.
Claim 19
Dependent Claim
29 words
The method of claim 13 wherein said second layer is deposited and said reflow is performed under high vacuum to ultra high vacuum conditions within the same vacuum system.
Claim 20
Dependent Claim
17 words
The method of claim 13 wherein said reflow is performed at a temperature below approximately 500° C.
Claim 21
Dependent Claim
38 words
The method of claim 13 further comprising the step of chemically-mechanically etching at least a portion of said second layer which exists outside said recessed region such that said second layer becomes substantially isolated within said recessed region.
Claim 22
Dependent Claim
25 words
The method of claim 15 wherein said wetting layer comprises a material selected from the group consisting of silicon nitride, Ta, and any combination thereof.
References Cited (Backward Citations)
US4641420A
Cited
US4832788A
Cited
US5098852A
Cited
US5198154A
Cited
US5043300A
Cited
US5213638A
Cited
US5032233A
Cited
US5266521A
Cited
US5124780A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-08-04 | 2001-02-03 | 2001-08-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-08-04 | 2005-02-03 | 2005-08-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-08-04 | 2009-02-03 | 2009-08-05 | $7700.00 | Window Closed / Lapsed |