US4690730A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Oxide-capped titanium silicide formation
Assignee: Texas Instruments Inc
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Filing: 1986-06-20
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Granted: 1987-09-01
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Expires: 2006-06-20
Abstract
Abstract A cap oxide (or oxide/nitride) prevents silicon outdiffusion during the reaction step which forms direct-react titanium silicide.
Inventors
- 👤 Thomas E. Tang
- 👤 Che-Chia Wei
- 👤 Roger A. Haken
- 👤 Thomas C. Holloway
- 👤 David A. Bell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:37
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/01; H10D30/021; H10D30/0223; H10D30/0227; H10D64/00; H10D64/01; H10D64/011; H10D64/0111; H10D64/0112; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/0698
Claims Analysis
Total Claims: 57
Claim 1
Independent Claim
100 words
A method for fabricating integrated circuit devices, comprising the steps of: (a) providing a substrate having thereon a partially fabricated integrated circuit structure including exposed portions consisting essentially of silicon; (b) depositing overall a metal layer consisting predominantly of titanium; (c) providing a dielectric layer directly overlying at least predetermined portions of said metal layer, said dielectric layer consisting predominantly of oxides; and (d) applying heat until portions of said metal layer react with portions of said exposed silicon to form titanium silicides; whereby said dielectric layer suppresses silicon outdiffusion through portions of said metal layer under said dielectric layer.
Claim 2
Independent Claim
100 words
A method for fabricating integrated circuit devices, comprising the steps of: (a) providing a substrate having thereon a partially fabricated integrated circuit structure including exposed portions consisting essentially of silicon; (b) depositing overall a metal layer consisting predominantly of titanium; (c) providing a dielectric layer directly overlying at least predetermined portions of said metal layer, said dielectric layer consisting predominantly of oxides; and (d) applying heat until portions of said metal layer react with portions of said exposed silicon to form titanium silicides; whereby said dielectric layer suppresses silicon outdiffusion through portions of said metal layer under said dielectric layer.
Claim 3
Dependent Claim
64 words
The method of claim 1 further comprising the additional steps, subsequent to said step (d), of (e) removing predetermined portions of said dielectric layer and/or of the remainder of said metal layer in a predetermined pattern to define local interconnects; and (f) applying heat in a nitrogen atmosphere to convert remaining portions of metal layer to a conductive material consisting predominantly of titanium nitride.
Claim 4
Dependent Claim
58 words
The method of claim 1 further comprising the additional steps, subsequent of step (d), of (e) removing said dielectric layer; (f) applying heat in a nitrogen atmosphere to convert remaining portions of metal layer to a conductive material consisting predominantly of titanium nitride; and (g) etching said conductive material in a predetermined pattern to provide local interconnect lines.
Claim 5
Dependent Claim
65 words
The method of claim 1 further comprising the additional steps, subsequent to said step (d), of (e) removing said dielectric layer; (f) etching remaining portions of said metal layer in a predetermined pattern corresponding to locations of local interconnect lines; and (g) applying heat in a nitrogen atmosphere to convert remaining portions of said metal layer to a conductive material consisting predominantly of titanium nitride.
Claim 6
Independent Claim
146 words
A method for fabricating integrated circuit devices, comprising the steps of: (a) providing a substrate having thereon a partially fabricated integrated circuit structure including exposed portions consisting essentially of silicon; (b) depositing overall a metal layer, said metal (1) being capable of forming a conductive silicide by thermal reaction. (2) not allowing silicon diffusion through said metal (at temperatures suitable for said silicide formation) if said metal is passivated with oxygen, and (3) being capable of reducing SiO 2 (at temperatures suitable for said silicide formation); (c) providing a dielectric layer directly overlying at least predetermined portions of said metal layer, said dielectric layer consisting predominantly of oxides; and (d) applying heat until portions of said metal layer react with portions of said exposed silicon to form titanium silicides; whereby said dielectric layer suppresses silicon outdiffusion through portions of said metal layer under said dielectric layer.
Claim 7
Independent Claim
146 words
A method for fabricating integrated circuit devices, comprising the steps of: (a) providing a substrate having thereon a partially fabricated integrated circuit structure including exposed portions consisting essentially of silicon; (b) depositing overall a metal layer, said metal (1) being capable of forming a conductive silicide by thermal reaction. (2) not allowing silicon diffusion through said metal (at temperatures suitable for said silicide formation) if said metal is passivated with oxygen, and (3) being capable of reducing SiO 2 (at temperatures suitable for said silicide formation); (c) providing a dielectric layer directly overlying at least predetermined portions of said metal layer, said dielectric layer consisting predominantly of oxides; and (d) applying heat until portions of said metal layer react with portions of said exposed silicon to form titanium silicides; whereby said dielectric layer suppresses silicon outdiffusion through portions of said metal layer under said dielectric layer.
Claim 8
Dependent Claim
16 words
The method of claim 1 wherein said metal layer comprises more than 50% atomic of titanium.
Claim 9
Dependent Claim
13 words
The method of claim 1 wherein said metal layer consists essentially of titanium.
Claim 10
Dependent Claim
18 words
The method of claim 1 wherein said metal layer is deposited to a thickness less than 2000 A.
Claim 11
Dependent Claim
14 words
The method of claim 1 wherein said dielectric layer consists essentially of silicon oxides.
Claim 12
Dependent Claim
32 words
The method of claim 1 wherein said dielectric layer is formed as a layered structure, and the portion of said dielectric layer closest to said metal layer consists essentially of silicon oxides.
Claim 13
Dependent Claim
45 words
The method of claim 1 wherein said dielectric layer is formed as a layered structure, and the portion of said dielectric layer closest to said metal layer consists essentially of an oxide having a heat of formation substantially less than that of TiO 2 .
Claim 14
Dependent Claim
16 words
The method of claim 1 wherein said dielectric layer consists essentially of a low-density silicon oxide.
Claim 15
Dependent Claim
22 words
The method of claim 1, wherein said dielectric layer consists essentially of a low-density silicon oxide including a large fraction of hydrogen.
Claim 16
Dependent Claim
47 words
The method of claim 1 wherein said dielectric layer is formed as a layered structure, and the portion of said dielectric layer closest to said metal layer consists predominantly of silicon oxides, and at least one other portion of said layered structure consists essentially of silicon nitride.
Claim 17
Dependent Claim
55 words
The method of claim 1 wherein said dielectric layer is formed as a layered structure, and the portion of said dielectric layer closest to said metal layer consists predominantly of silicon oxides, and at least one other portion of said layered structure consists essentially of a material which will provide a diffusion barrier to oxygen.
Claim 18
Dependent Claim
16 words
The method of claim 2 wherein said metal layer comprises more than 50% atomic of titanium.
Claim 19
Dependent Claim
13 words
The method of claim 2 wherein said metal layer consists essentially of titanium.
Claim 20
Dependent Claim
18 words
The method of claim 2 wherein said metal layer is deposited to a thickness less than 2000 A.
Claim 21
Dependent Claim
14 words
The method of claim 2 wherein said dielectric layer consists essentially of silicon oxides.
Claim 22
Dependent Claim
32 words
The method of claim 2 wherein said dielectric layer is formed as a layered structure, and the portion of said dielectric layer closest to said metal layer consists essentially of silicon oxides.
Claim 23
Dependent Claim
45 words
The method of claim 2 wherein said dielectric layer is formed as a layered structure, and the portion of said dielectric layer closest to said metal layer consists essentially of an oxide having a heat of formation substantially less than that of TiO 2 .
Claim 24
Dependent Claim
16 words
The method of claim 2 wherein said dielectric layer consists essentially of a low-density silicon oxide.
Claim 25
Dependent Claim
22 words
The method of claim 2 wherein said dielectric layer consists essentially of a low-density silicon oxide including a large fraction of hydrogen.
Claim 26
Dependent Claim
47 words
The method of claim 2 wherein said dielectric layer is formed as a layered structure, and the portion of said dielectric layer closest to said metal layer consists predominantly of silicon oxides, and at least one other portion of said layered structure consists essentially of silicon nitride.
Claim 27
Dependent Claim
55 words
The method of claim 2 wherein said dielectric layer is formed as a layered structure, and the portion of said dielectric layer closest to said metal layer consists predominantly of silicon oxides, and at least one other portion of said layered structure consists essentially of a material which will provide a diffusion barrier to oxygen.
Claim 28
Dependent Claim
16 words
The method of claim 3 wherein said metal layer comprises more than 50% atomic of titanium.
Claim 29
Dependent Claim
13 words
The method of claim 3 wherein said metal layer consists essentially of titanium.
Claim 30
Dependent Claim
18 words
The method of claim 3, wherein said metal layer is deposited to a thickness less than 2000 A.
Claim 31
Dependent Claim
14 words
The method of claim 3, wherein said dielectric layer consists essentially of silicon oxides.
Claim 32
Dependent Claim
32 words
The method of claim 3 wherein said dielectric layer is formed as a layered structure, and the portion of said dielectric layer closest to said metal layer consists essentially of silicon oxides.
Claim 33
Dependent Claim
45 words
The method of claim 3 wherein said dielectric layer is formed as a layered structure, and the portion of said dielectric layer closest to said metal layer consists essentially of an oxide having a heat of formation substantially less than that of TiO 2 .
Claim 34
Dependent Claim
16 words
The method of claim 3 wherein said dielectric layer consists essentially of a low-density silicon oxide.
Claim 35
Dependent Claim
22 words
The method of claim 3 wherein said dielectric layer consists essentially of a low-density silicon oxide including a large fraction of hydrogen.
Claim 36
Dependent Claim
47 words
The method of claim 3 wherein said dielectric layer is formed as a layered structure, and the portion of said dielectric layer closest to said metal layer consists predominantly of silicon oxides, and at least one other portion of said layered structure consists essentially of silicon nitride.
Claim 37
Dependent Claim
55 words
The method of claim 3 wherein said dielectric layer is formed as a layered structure, and the portion of said dielectric layer closest to said metal layer consists predominantly of silicon oxides, and at least one other portion of said layered structure consists essentially of a material which will provide a diffusion barrier to oxygen.
Claim 38
Dependent Claim
16 words
The method of claim 4 wherein said metal layer comprises more than 50% atomic of titanium.
Claim 39
Dependent Claim
13 words
The method of claim 4 wherein said metal layer consists essentially of titanium.
Claim 40
Dependent Claim
18 words
The method of claim 4 wherein said metal layer is deposited to a thickness less than 2000 A.
Claim 41
Dependent Claim
14 words
The method of claim 4 wherein said dielectric layer consists essentially of silicon oxides.
Claim 42
Dependent Claim
32 words
The method of claim 4 wherein said dielectric layer is formed as a layered structure, and the portion of said dielectric layer closest to said metal layer consists essentially of silicon oxides.
Claim 43
Dependent Claim
45 words
The method of claim 4 wherein said dielectric layer is formed as a layered structure, and the portion of said dielectric layer closest to said metal layer consists essentially of an oxide having a heat of formation substantially less than that of TiO 2 .
Claim 44
Dependent Claim
16 words
The method of claim 4 wherein said dielectric layer consists essentially of a low-density silicon oxide.
Claim 45
Dependent Claim
22 words
The method of claim 4 wherein said dielectric layer consists essentially of a low-density silicon oxide including a large fraction of hydrogen.
Claim 46
Dependent Claim
47 words
The method of claim 4 wherein said dielectric layer is formed as a layered structure and the portion of said dielectric layer closest to said metal layer consists predominantly of silicon oxides, and at least one other portion of said layered structure consists essentially of silicon nitride.
Claim 47
Dependent Claim
55 words
The method of claim 4 wherein said dielectric layer is formed as a layered structure, and the portion of said dielectric layer closest to said metal layer consists predominantly of silicon oxides, and at least one other portion of said layered structure consists essentially of a material which will provide a diffusion barrier to oxygen.
Claim 48
Dependent Claim
16 words
The method of claim 5 wherein said metal layer comprises more than 50% atomic of titanium.
Claim 49
Dependent Claim
13 words
The method of claim 5 wherein said metal layer consists essentially of titanium.
Claim 50
Dependent Claim
18 words
The method of claim 5 wherein said metal layer is deposited to a thickness less than 2000 A.
Claim 51
Dependent Claim
14 words
The method of claim 5 wherein said dielectric layer consists essentially of silicon oxides.
Claim 52
Dependent Claim
32 words
The method of claim 5 wherein said dielectric layer is formed as a layered structure, and the portion of said dielectric layer closest to said metal layer consists essentially of silicon oxides.
Claim 53
Dependent Claim
45 words
The method of claim 5 wherein said dielectric layer is formed as a layered structure, and the portion of said dielectric layer closest to said metal layer consists essentially of an oxide having a heat of formation substantially less than that of TiO 2 .
Claim 54
Dependent Claim
16 words
The method of claim 5 wherein said dielectric layer consists essentially of a low-density silicon oxide.
Claim 55
Dependent Claim
22 words
The method of claim 5 wherein said dielectric layer consists essentially of a low-density silicon oxide including a large fraction of hydrogen.
Claim 56
Dependent Claim
47 words
The method of claim 5 wherein said dielectric layer is formed as a layered structure, and the portion of said dielectric layer closest to said metal layer consists predominantly of silicon oxides, and at least one other portion of said layered structure consists essentially of slicon nitride.
Claim 57
Dependent Claim
55 words
The method of claim 5 wherein said dielectric layer is formed as a layered structure, and the portion of said dielectric layer closest to said metal layer consists predominantly of silicon oxides, and at least one other portion of said layered structure consists essentially of a material which will provide a diffusion barrier to oxygen.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-08-31 | 1991-03-02 | 1991-09-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-31 | 1995-03-02 | 1995-09-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-31 | 1999-03-02 | 1999-09-01 | $7700.00 | Window Closed / Lapsed |