Patent US5378660A successfully refreshed from Google Patents.
US5378660A
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Barrier layers and aluminum contacts
Assignee: Applied Materials Inc
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Filing: 1993-02-12
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Granted: 1995-01-03
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Expires: 2013-02-12
Abstract
Abstract In the manufacture of high temperature deposited aluminum contacts onto silicon substrates wherein a barrier layer of titanium nitride is used, the improvement wherein the titanium nitride contains oxygen. The improved contacts are made by depositing a titanium-containing layer onto a silicon substrate, performing a first, high temperature nitrogen anneal in vacuum to form a low resistance TiSix contact to the silicon, and performing a second, lower temperature anneal in vacuum using a mixture of nitrogen and oxygen to add oxygen to the titanium nitride layer. This oxygen-containing titanium nitride layer provides an improved barrier to a subsequently deposited high temperature deposited aluminum layer.
Inventors
- 👤 Kenny K. Ngan
- 👤 Edith Ong
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 15:04
CPC Classifications
C; C23; C23C; C23C14/00; C23C14/58; C23C14/5806; C23C14/06; C23C14/0641; C23C14/5846; C23C14/5853; C23C14/586; C23C14/5873; C23C14/5893; H; H10; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/032; H10W20/033; H10W20/047; H10W20/048; H10W20/40; H10W20/41; H10W20/425; Y; Y10; Y10S; Y10S148/00; Y10S148/003
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
75 words
A method of forming a titanium nitride barrier layer which comprises the following steps in sequence a) depositing a titanium-containing layer on a substrate in a vacuum environment; b) annealing said layer in nitrogen under vacuum at a temperature of from about 750°-850° C.; and c) annealing said layer in nitrogen containing from about 3-15% by volume of oxygen under vacuum at a temperature of from about 500°-550° C. without removing the substrate from vacuum.
Claim 2
Independent Claim
75 words
A method of forming a titanium nitride barrier layer which comprises the following steps in sequence a) depositing a titanium-containing layer on a substrate in a vacuum environment; b) annealing said layer in nitrogen under vacuum at a temperature of from about 750°-850° C.; and c) annealing said layer in nitrogen containing from about 3-15% by volume of oxygen under vacuum at a temperature of from about 500°-550° C. without removing the substrate from vacuum.
Claim 3
Dependent Claim
19 words
The method according to claim 1 wherein from about 5-10% by volume of oxygen is added in step c).
Claim 4
Dependent Claim
23 words
The method according to claim 1 wherein said titanium-containing layer comprises a first layer of titanium and a second layer of titanium nitride.
Claim 5
Dependent Claim
13 words
The method according to claim 1 wherein said titanium-containing layer is sputter deposited.
Claim 6
Dependent Claim
13 words
The method according to claim 3 wherein said titanium-containing layer is sputter deposited.
Claim 7
Dependent Claim
17 words
The method according to claim 4 wherein said titanium-containing layers are sputter deposited through a collimation grating.
Claim 8
Dependent Claim
17 words
A method according to claim 5 wherein said titanium-containing layers are sputter deposited through a collimation grating.
Claim 9
Independent Claim
110 words
A method of forming an aluminum contact on a silicon substrate comprising the following steps in sequence: a) sputter depositing a titanium-containing layer over said silicon under vacuum; b) annealing said titanium-containing layer in nitrogen under vacuum at a temperature of from about 750°-850° C., thereby forming a titanium silicide interface; c) annealing said titanium-containing layer under nitrogen containing from about 3-15% by volume of oxygen under vacuum at a temperature of from about 500°-550° C., thereby forming an oxygen-containing titanium nitride layer without removing the substrate from vacuum; and d) sputter depositing an aluminum layer over the stuffed titanium nitride layer at a temperature of over about 400° C.
Claim 10
Independent Claim
110 words
A method of forming an aluminum contact on a silicon substrate comprising the following steps in sequence: a) sputter depositing a titanium-containing layer over said silicon under vacuum; b) annealing said titanium-containing layer in nitrogen under vacuum at a temperature of from about 750°-850° C., thereby forming a titanium silicide interface; c) annealing said titanium-containing layer under nitrogen containing from about 3-15% by volume of oxygen under vacuum at a temperature of from about 500°-550° C., thereby forming an oxygen-containing titanium nitride layer without removing the substrate from vacuum; and d) sputter depositing an aluminum layer over the stuffed titanium nitride layer at a temperature of over about 400° C.
Claim 11
Dependent Claim
19 words
The method according to claim 8 wherein from about 5-10% by volume of oxygen is present in step c).
Claim 12
Dependent Claim
23 words
The method according to claim 8 wherein said titanium-containing layer comprises a first layer of titanium and a second layer of titanium nitride.
Claim 13
Dependent Claim
13 words
The method according to claim 8 wherein said titanium-containing layer is sputter deposited.
Claim 14
Dependent Claim
13 words
The method according to claim 10 wherein said titanium-containing layers are sputter deposited.
Claim 15
Dependent Claim
17 words
The method according to claim 11 wherein said titanium-containing layer is sputter deposited through a collimation grating.
Claim 16
Dependent Claim
17 words
The method according to claim 12 wherein said titanium-containing layers are sputter deposited through a collimation grating.
Claim 17
Dependent Claim
21 words
The method according to claim 8 wherein said aluminum layer is sputter deposited at a temperature of over about 400° C.
Claim 18
Dependent Claim
21 words
The method according to claim 8 wherein all of steps a) to d) are performed without removing the substrate from vacuum.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1998-01-02 | 1998-07-04 | 1999-01-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-01-02 | 2002-07-04 | 2003-01-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-01-02 | 2006-07-04 | 2007-01-03 | $7700.00 | Window Closed / Lapsed |