Patent US5504043A successfully refreshed from Google Patents.
US5504043A
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Barrier layers and aluminum contacts
Assignee: Applied Materials Inc
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Filing: 1994-09-26
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Granted: 1996-04-02
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Expires: 2014-09-26
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 stuff the titanium nitride layer. This stuffed 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
2026-11-09 11:00
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: 14
Claim 1
Independent Claim
90 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 silicon substrate in a vacuum environment; b) annealing said layer in nitrogen under vacuum at a temperature sufficient to form a TiSi x contact; and c) annealing said layer in nitrogen containing a sufficient volume of oxygen under vacuum at a lower temperature than step b) and sufficient to anneal said layer and add oxygen to the resultant titanium nitride layer, without removing the substrate from vacuum.
Claim 2
Independent Claim
90 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 silicon substrate in a vacuum environment; b) annealing said layer in nitrogen under vacuum at a temperature sufficient to form a TiSi x contact; and c) annealing said layer in nitrogen containing a sufficient volume of oxygen under vacuum at a lower temperature than step b) and sufficient to anneal said layer and add oxygen to the resultant titanium nitride layer, without removing the substrate from vacuum.
Claim 3
Dependent Claim
23 words
A method according to claim 1 wherein said titanium-containing layer comprises a first layer of titanium and a second layer of titanium nitride.
Claim 4
Dependent Claim
13 words
A method according to claim 1 wherein said titanium-containing layer is sputter deposited.
Claim 5
Dependent Claim
17 words
A method according to claim 3 wherein said titanium-containing layer is sputter deposited through a collimation grating.
Claim 6
Dependent Claim
17 words
A method according to claim 2 wherein said titanium-containing layer is sputter deposited through a collimation grating.
Claim 7
Independent Claim
110 words
A method of forming an improved aluminum contact to a silicon substrate comprising the following steps in sequence: a) sputter depositing a titanium-containing layer over said silicon; b) annealing said titanium-containing layer under nitrogen under vacuum at a temperature sufficient to form a titanium silicide contact at the interface between said titanium-containing layer and said silicon; c) heating the layer from step b) at a lower temperature in the presence of nitrogen containing oxygen, without removing the substrate from vacuum, said temperature high enough so that an oxygen-containing titanium nitride layer is formed over said silicide layer; and d) sputter depositing an aluminum layer over the oxygen-containing titanium nitride layer.
Claim 8
Independent Claim
110 words
A method of forming an improved aluminum contact to a silicon substrate comprising the following steps in sequence: a) sputter depositing a titanium-containing layer over said silicon; b) annealing said titanium-containing layer under nitrogen under vacuum at a temperature sufficient to form a titanium silicide contact at the interface between said titanium-containing layer and said silicon; c) heating the layer from step b) at a lower temperature in the presence of nitrogen containing oxygen, without removing the substrate from vacuum, said temperature high enough so that an oxygen-containing titanium nitride layer is formed over said silicide layer; and d) sputter depositing an aluminum layer over the oxygen-containing titanium nitride layer.
Claim 9
Dependent Claim
13 words
A method according to claim 6 wherein said titanium-containing layer is sputter deposited.
Claim 10
Dependent Claim
17 words
A method according to claim 7 wherein said titanium-containing layer is sputter deposited thorough a collimation grating.
Claim 11
Dependent Claim
23 words
A method according to claim 6 wherein said titanium-containing layer comprises a first layer of titanium and a second layer of titanium nitride.
Claim 12
Dependent Claim
13 words
A method according to claim 9 wherein said titanium-containing layers are sputter deposited.
Claim 13
Dependent Claim
17 words
A method according to claim 10 wherein said titanium-containing layers are sputter deposited through a collimation grating.
Claim 14
Dependent Claim
22 words
A method according to claim 6 wherein all of steps a) through d) are carried out without removing said substrate from vacuum.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-04-02 | 1999-10-02 | 2000-04-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-04-02 | 2003-10-02 | 2004-04-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-04-02 | 2007-10-02 | 2008-04-02 | $7700.00 | Window Closed / Lapsed |