Patent US622482A successfully refreshed from Google Patents.
Patent US5747361A successfully refreshed from Google Patents.
← Back to Patent Explorer
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
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

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 12:35
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

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag