US5747361A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stabilization of the interface between aluminum and titanium nitride
Assignee: Teledyne Digital Imaging Inc
•
Filing: 1995-10-16
•
Granted: 1998-05-05
•
Expires: 2015-10-16
Abstract
Abstract A semiconductor device comprises at least one metal interconnect layer, a titanium-based barrier layer in contact with the metal interconnect layer. The metal interconnect layer contains titanium in an amount up to the limit of solid solubility at the peritectic temperature. The arrangement is effective to reduce hillock, spike, and notch formation in the semiconductor device.
Inventors
- 👤 Luc Ouellet
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 06:19
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/40; H10W20/41; H10W20/42; H10P; H10P14/00; H10P14/40; H10P14/42; H10P14/44; H10W20/01; H10W20/031; H10W20/032; H10W20/038; H10W20/425; Y; Y10; Y10S; Y10S438/00; Y10S438/937
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
140 words
A method of making a semiconductor device comprising the steps of: a) depositing a first interconnect layer of a first metal on a substrate; b) forming a barrier layer having an upper surface on said first interconnect layer to prevent hillock formation during subsequent processing at an elevated temperature of at least 350° C., said barrier layer comprising a compound of a second metal; c) depositing a dielectric layer directly onto said upper surface of said barrier layer; and d) subsequently subjecting said device to said elevated temperature of at least 350° C. for subsequent processing; wherein said first interconnect layer is an alloy pre-saturated with said second metal in amount at least equal to the limit of solid solubility of the second metal in said first metal at said particular elevated temperature at which said subsequent processing takes place.
Claim 2
Independent Claim
140 words
A method of making a semiconductor device comprising the steps of: a) depositing a first interconnect layer of a first metal on a substrate; b) forming a barrier layer having an upper surface on said first interconnect layer to prevent hillock formation during subsequent processing at an elevated temperature of at least 350° C., said barrier layer comprising a compound of a second metal; c) depositing a dielectric layer directly onto said upper surface of said barrier layer; and d) subsequently subjecting said device to said elevated temperature of at least 350° C. for subsequent processing; wherein said first interconnect layer is an alloy pre-saturated with said second metal in amount at least equal to the limit of solid solubility of the second metal in said first metal at said particular elevated temperature at which said subsequent processing takes place.
Claim 3
Dependent Claim
23 words
A method as claimed in claim 1, wherein said compound of said second metal is titanium nitride and said second metal is titanium.
Claim 4
Dependent Claim
23 words
A method as claimed in claim 1, wherein said first metal is selected from the group consisting of: aluminum, gold, tungsten and copper.
Claim 5
Dependent Claim
21 words
A method as claimed in claim 2, wherein the titanium nitride in said barrier layer is a stoichiometric single-phase, face-centered δ-TiN.
Claim 6
Dependent Claim
22 words
A method as claimed in claim 2, wherein the titanium nitride in the barrier layer is non-stoichiometric single phase face-centered cubic δ-TiN.
Claim 7
Dependent Claim
20 words
A method as claimed in claim 2, wherein the titanium nitride in said barrier layer is tetragonal ε-Ti 2 N.
Claim 8
Dependent Claim
49 words
A method as claimed in claim 2, wherein the titanium nitride in the barrier layer is a solid solution of two or more of the compounds selected from the group consisting of: stoichiometric single phase, face-centered cubic δ-TiN; non stoichiometric single phase face-centered δ-TiN; and tetragonal ε-Ti 2 N.
Claim 9
Dependent Claim
41 words
A method as claimed in claim 2, wherein said first metal is aluminum, and said first interconnect layer contains titanium in an amount between 0.05 wt % and the limit of solid solubility at the peritectic temperature of said first metal.
Claim 10
Dependent Claim
27 words
A method as claimed in claim 8, wherein the amount of titanium in the first interconnect layer is the limit of solid solubility at the peritectic temperature.
Claim 11
Dependent Claim
46 words
A method as claimed in claim 8, wherein the titanium nitride in the barrier layer is a solid solution of two or more compounds selected from the group consisting of: stoichiometric single phase, face-centered cubic δ-TiN, non-stoichiometric single phase face-centered δ-TiN, and tetragonal ε-Ti 2 N.
Claim 12
Independent Claim
120 words
A method of making a semiconductor device comprising the steps of: a) depositing an aluminum alloy interconnect layer on a substrate; b) forming a TiN barrier layer having an upper surface on said aluminum layer to prevent hillock formation during subsequent processing at an elevated temperature of at least 350° C.; c) depositing a dielectric layer directly onto said upper surface of said TiN barrier layer; d) subsequently subjecting said device to said elevated temperature of at least 350° C. for subsequent processing; and said aluminum alloy interconnect layer being pre-saturated with titanium in amount at least equal to the limit of solid solubility of titanium in aluminum at said particular elevated temperature at which said subsequent processing takes place.
Claim 13
Independent Claim
120 words
A method of making a semiconductor device comprising the steps of: a) depositing an aluminum alloy interconnect layer on a substrate; b) forming a TiN barrier layer having an upper surface on said aluminum layer to prevent hillock formation during subsequent processing at an elevated temperature of at least 350° C.; c) depositing a dielectric layer directly onto said upper surface of said TiN barrier layer; d) subsequently subjecting said device to said elevated temperature of at least 350° C. for subsequent processing; and said aluminum alloy interconnect layer being pre-saturated with titanium in amount at least equal to the limit of solid solubility of titanium in aluminum at said particular elevated temperature at which said subsequent processing takes place.
Claim 14
Dependent Claim
21 words
A method as claimed in claim 11 wherein said post treatment temperature is above 450° C. and lower than 550° C.
References Cited (Backward Citations)
JPS5846641A
Cited
JPS58139426A
Cited
JPS639971A
Cited
JPS63129662A
Cited
EP0276087A2
Cited
US4820611A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-05-04 | 2001-11-03 | 2002-05-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-05-04 | 2005-11-03 | 2006-05-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-05-04 | 2009-11-03 | 2010-05-05 | $7700.00 | Window Closed / Lapsed |