Patent US5652181A successfully refreshed from Google Patents.
US5652181A
Expired / Lapsed
US
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Thermal process for forming high value resistors
Assignee: Micron Technology Inc
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Filing: 1996-01-16
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Granted: 1997-07-29
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Expires: 2016-01-16
Abstract
Abstract The present invention develops several methods used in a semiconductor fabrication process to form a resistive material having a specific resistive value. A first method uses the steps of: forming a titanium layer over a silicon substrate; and subjecting the titanium layer to a rapid thermal processing cycle. A second method uses the steps of: forming a titanium layer over a silicon substrate; subjecting the titanium layer to a rapid thermal processing cycle; and forming a titanium nitride layer over the thermally processed titanium. A third method uses the steps of: forming an insulating layer over a silicon substrate; forming an undoped polysilicon layer over the insulating layer; forming a titanium layer over the polysilicon layer; subjecting the titanium layer to a rapid thermal processing cycle; and forming a titanium nitride layer over the thermally processed titanium. Additionally, the resistive structure can be capped using a nitride layer.
Inventors
- 👤 Randhir P. S. Thakur
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 14:17
CPC Classifications
H; H10; H10D; H10D1/00; H10D1/40; H10D1/47; H10D1/474; Y; Y10; Y10S; Y10S148/00; Y10S148/136
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
107 words
A semiconductor fabrication process to form a resistive material having a specific resistive value, said process comprising the steps of: forming a refractory metal layer over a supporting substrate; and thermally processing said refractory metal layer at a temperature ranging from 700°-850° C. in the presence of an ambient gas consisting of a combination of nitrogen and oxygen; wherein said step of thermally processing is performed at a controlled temperature and with a controlled amount of ambient gas such a desired said specific resistive value is formed by altering the sheet resistance of the refractory metal layer obtained during said step of forming a refractory metal layer.
Claim 2
Dependent Claim
107 words
A semiconductor fabrication process to form a resistive material having a specific resistive value, said process comprising the steps of: forming a refractory metal layer over a supporting substrate; and thermally processing said refractory metal layer at a temperature ranging from 700°-850° C. in the presence of an ambient gas consisting of a combination of nitrogen and oxygen; wherein said step of thermally processing is performed at a controlled temperature and with a controlled amount of ambient gas such a desired said specific resistive value is formed by altering the sheet resistance of the refractory metal layer obtained during said step of forming a refractory metal layer.
Claim 3
Dependent Claim
24 words
The process of claim 1 further, comprising the additional step of forming a specific resistance capping layer superjacent said thermally processed refractory metal layer.
Claim 4
Dependent Claim
19 words
The process of claim 2, wherein said specific resistance capping layer comprises a nitride of said refractory metal layer.
Claim 5
Dependent Claim
16 words
The process of claim 1, wherein said refractory metal is converted to a refractory metal nitride.
Claim 6
Dependent Claim
11 words
The process of claim 1, wherein said refractory metal is titanium.
Claim 7
Dependent Claim
19 words
The process of claim 1, wherein a portion of said refractory metal is converted to a refractory metal nitride.
Claim 8
Dependent Claim
28 words
The process of claim 1, wherein said step of thermally processing is a process selected from the group consisting of rapid thermal processing, plasma annealing and furnace annealing.
Claim 9
Dependent Claim
34 words
The process of claim 1, wherein said step of forming a said refractory metal layer is a forming method selected from the group consisting of chemical vapor deposition, molecular beam epitaxy, sputtering, and MOCVD.
Claim 10
Dependent Claim
126 words
A semiconductor fabrication process to form a resistive material having a specific resistive value, said process comprising the steps of: forming an insulation layer over a supporting substrate; forming a semiconductive layer over said insulating layer; forming a refractory metal layer over said semiconductive layer; and thermally processing the existing material on said supporting substrate at a temperature ranging from 700°-850° C. in the presence of an ambient gas consisting of a combination of nitrogen and oxygen; wherein said step of thermally processing is performed at a controlled temperature and with a controlled amount of ambient gas such a desired said specific resistive value is formed by altering the sheet resistance of the refractory metal layer obtained during said step of forming a refractory metal layer.
Claim 11
Dependent Claim
126 words
A semiconductor fabrication process to form a resistive material having a specific resistive value, said process comprising the steps of: forming an insulation layer over a supporting substrate; forming a semiconductive layer over said insulating layer; forming a refractory metal layer over said semiconductive layer; and thermally processing the existing material on said supporting substrate at a temperature ranging from 700°-850° C. in the presence of an ambient gas consisting of a combination of nitrogen and oxygen; wherein said step of thermally processing is performed at a controlled temperature and with a controlled amount of ambient gas such a desired said specific resistive value is formed by altering the sheet resistance of the refractory metal layer obtained during said step of forming a refractory metal layer.
Claim 12
Dependent Claim
28 words
The process of claim 9, wherein said step of thermally processing is a process selected from the group consisting of rapid thermal processing, plasma annealing and furnace annealing.
Claim 13
Dependent Claim
19 words
The process of claim 9, wherein said forming of all layers comprises depositing these layers by chemical vapor deposition.
Claim 14
Dependent Claim
18 words
The process of claim 9, wherein said refractory metal layer is converted to a refractory metal nitride layer.
Claim 15
Dependent Claim
21 words
The process of claim 9, wherein a portion of said refractory metal layer is converted to a refractory metal nitride layer.
Claim 16
Dependent Claim
11 words
The process of claim 9, wherein said refractory metal is titanium.
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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) | 2000-07-28 | 2001-01-27 | 2001-07-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-07-28 | 2005-01-27 | 2005-07-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-07-28 | 2009-01-27 | 2009-07-29 | $7700.00 | Window Closed / Lapsed |