US5449640A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fabricating electrical contacts in semiconductor devices
Assignee: STMicroelectronics Ltd Great Britain
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Filing: 1991-07-19
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Granted: 1995-09-12
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Expires: 2011-07-19
Abstract
Abstract A method of fabricating an electrical contact in a semiconductor device comprises providing on an underlying silicon substrate a reflowable interlevel dielectric material having a contact opening exposing a contact region of the silicon substrate. The silicon substrate and the interlevel dielectric material are heated by a rapid thermal anneal in an oxygen-containing atmosphere thereby to grow an oxide control layer in the contact region and to reflow the dielectric material. A layer of transition metal is deposited over the reflowed dielectric material and the control layer and at least part of the transition metal layer is converted into a metallurgic barrier.
Inventors
- 👤 Paul A. Hunt
- 👤 Ian M. Liles
- 👤 David R. Guite
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 05:51
CPC Classifications
H; H10; H10D; H10D64/00; H10D64/01; H10D64/011; H10P; H10P95/00
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
110 words
A method of fabricating an electrical contact in a semiconductor device, the method comprising the steps of: providing on an underlying silicon substrate a reflowable interlevel dielectric material having a contact opening exposing a contact region of the silicon substrate; heating the silicon substrate and the interlevel dielectric material by a rapid thermal anneal in an oxygen-containing atmosphere thereby to grow an oxide control layer in the contact region and to reflow the dielectric material simultaneously, in a single step ; depositing a layer of transition metal over the reflowed dielectric material and the control layer; and converting at least part of the transition metal layer into a metallurgic barrier.
Claim 2
Independent Claim
110 words
A method of fabricating an electrical contact in a semiconductor device, the method comprising the steps of: providing on an underlying silicon substrate a reflowable interlevel dielectric material having a contact opening exposing a contact region of the silicon substrate; heating the silicon substrate and the interlevel dielectric material by a rapid thermal anneal in an oxygen-containing atmosphere thereby to grow an oxide control layer in the contact region and to reflow the dielectric material simultaneously, in a single step ; depositing a layer of transition metal over the reflowed dielectric material and the control layer; and converting at least part of the transition metal layer into a metallurgic barrier.
Claim 3
Dependent Claim
31 words
A method according to claim 1 further comprising the steps of depositing an interconnect layer including aluminium over the metallurgic barrier and depositing a capping metal layer over the interconnect layer.
Claim 4
Dependent Claim
13 words
A method according to claim 2 wherein the capping metal layer comprises titanium.
Claim 5
Dependent Claim
17 words
A method according to claim 1, wherein the reflowable dielectric material comprises a boron phosphorous silicon glass.
Claim 6
Dependent Claim
14 words
A method according to claim 1 wherein the layer of transition metal comprises titanium.
Claim 7
Dependent Claim
23 words
A method according to claim 5 wherein the metallurgic barrier comprises titanium nitride and is formed by nitridation of the layer of titanium.
Claim 8
Independent Claim
117 words
A method of fabricating an electrical contact in a semiconductor device, the method comprising the steps of: providing on an underlying silicon substrate a reflowable interlevel dielectric material having a contact opening exposing a contact region of the silicon substrate; heating the silicon substrate and the interlevel dielectric material by a rapid thermal anneal at a temperature of 950° to 1050° C. in an oxygen-containing atmosphere thereby to grow an oxide control layer in the contact region and to reflow the dielectric material simultaneously, in a single step; depositing a layer of transition metal over the reflowed dielectric material and the control layer; and converting at least part of the transition metal layer into a metallurgic barrier.
Claim 9
Independent Claim
117 words
A method of fabricating an electrical contact in a semiconductor device, the method comprising the steps of: providing on an underlying silicon substrate a reflowable interlevel dielectric material having a contact opening exposing a contact region of the silicon substrate; heating the silicon substrate and the interlevel dielectric material by a rapid thermal anneal at a temperature of 950° to 1050° C. in an oxygen-containing atmosphere thereby to grow an oxide control layer in the contact region and to reflow the dielectric material simultaneously, in a single step; depositing a layer of transition metal over the reflowed dielectric material and the control layer; and converting at least part of the transition metal layer into a metallurgic barrier.
Claim 10
Dependent Claim
31 words
A method according to claim 7 further comprising the steps of depositing an interconnect layer including aluminum over the metallurgic barrier and depositing a capping metal layer over the interconnect layer.
Claim 11
Dependent Claim
13 words
A method according to claim 8 wherein the capping metal layer comprises titanium.-
Claim 12
Dependent Claim
17 words
A method according to claim 7 wherein the reflowable dielectric material comprises a boron phosphorus silicon glass.
Claim 13
Dependent Claim
14 words
A method according to claim 7 wherein the layer of transition metal comprises titanium.
Claim 14
Dependent Claim
23 words
A method according to claim 11 wherein the metallurgic barrier comprises titanium nitride and is formed by nitridation of the layer of titanium.
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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) | 1998-09-11 | 1999-03-13 | 1999-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-09-11 | 2003-03-13 | 2003-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-09-11 | 2007-03-13 | 2007-09-12 | $7700.00 | Window Closed / Lapsed |