US4472237A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reactive ion etching of tantalum and silicon
Assignee: Nokia Bell Labs
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Filing: 1982-12-13
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Granted: 1984-09-18
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Expires: 2002-12-13
Abstract
Abstract A method for fabricating a device which includes a tantalum silicide structure, and which is essentially free of conductive etch residues, is disclosed. The method includes the steps of depositing tantalum and silicon onto a substrate, patterning the tantalum and silicon, and then sintering the patterned tantalum and silicon to form a patterned layer of tantalum silicide.
Inventors
- 👤 Jean S. Deslauriers
- 👤 Hyman J. Levinstein
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 21:13
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/26; H10P50/264; H10P50/266; H10P50/267; H10P50/268; H10D; H10D64/00; H10D64/01; H10D64/013; H10D64/01302; H10D64/01304; H10D64/01306; H10D64/01308; H10D64/01312; Y; Y10; Y10S; Y10S148/00; Y10S148/10; Y10S148/105
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
48 words
A method for fabricating a device, comprising the steps of: forming tantalum and silicon on a substrate, characterized in that said method further comprises the steps of patterning at least said tantalum, and then reacting said tantalum with said silicon to form a patterned layer of tantalum silicide.
Claim 2
Independent Claim
48 words
A method for fabricating a device, comprising the steps of: forming tantalum and silicon on a substrate, characterized in that said method further comprises the steps of patterning at least said tantalum, and then reacting said tantalum with said silicon to form a patterned layer of tantalum silicide.
Claim 3
Dependent Claim
10 words
The method of claim 1 wherein said patterning is anisotropic.
Claim 4
Dependent Claim
47 words
The method of claim 1 wherein said tantalum and silicon are formed by being deposited onto said substrate in the form of a layer containing an amorphous mixture of tantalum and silicon, and said patterning step includes the step of patterning said layer containing said amorphous mixture.
Claim 5
Dependent Claim
27 words
The method of claim 3 wherein said substrate includes a layer of polysilicon onto which said layer containing the amorphous mixture of tantalum and silicon is deposited.
Claim 6
Dependent Claim
25 words
The method of claim 4 wherein said step of patterning said layer containing said amorphous mixture includes the step of patterning said layer of polysilicon.
Claim 7
Dependent Claim
36 words
The method of claim 1 wherein said tantalum and silicon are formed by being deposited as successive layers of polysilicon and tantalum, and said patterning step includes the steps of patterning said tantalum and polysilicon layers.
Claim 8
Dependent Claim
35 words
The method of claim 1 wherein said tantalum and silicon are formed by being deposited as successive layers of polysilicon and tantalum, and said patterning step includes the step of patterning said layer of tantalum.
Claim 9
Dependent Claim
25 words
The method of claim 7 wherein said step of patterning said layer of tantalum includes the step of patterning a portion of said polysilicon layer.
Claim 10
Dependent Claim
29 words
The method of claim 7 wherein said sintering step reacts the tantalum and polysilicon layers to form a patterned layer of tantalum silicide overlying an unreacted layer of polysilicon.
Claim 11
Dependent Claim
16 words
The method of claim 9 further comprising the step of patterning the unreacted layer of polysilicon.
Claim 12
Dependent Claim
39 words
The method of claim 3 wherein said layer containing the amorphous mixture of tantalum and silicon is patterned by reactive ion etching said layer in a plasma which comprises active etchant radicals that include fluorine constituents as etching species.
Claim 13
Dependent Claim
35 words
The method of claim 6 or 7 wherein said layer of tantalum is patterned by reactive ion etching said layer in a plasma which comprises active etchant radicals that include fluorine constituents as etching species.
Claim 14
Dependent Claim
38 words
The method of claim 11 or 12 wherein said plasma is established in a gaseous atmosphere which includes a gas selected from the group consisting of CCl 3 F, CCl 2 F 2 , and CClF 3 .
Claim 15
Dependent Claim
79 words
The method of claim 13 wherein said reactive ion etching is accomplished by mounting said device on a driven electrode of a reactive ion etching apparatus, flowing said gas into said apparatus at a flow rate in the range 5 to 100 standard cubic centimeters per minute, maintaining a pressure of said gaseous atmosphere within said apparatus in the range 2 to 60 millitorr, and maintaining the power density in the range 0.05 to 1.0 watts per square centimeter.
Claim 16
Dependent Claim
46 words
The method of claim 14 wherein said flow rate is in the range 10 to 25 standard cubic centimeters per minute, said pressure is in the range 4 to 20 millitorr, and said power density is in the range 0.15 to 0.4 watts per square centimeter.
Claim 17
Dependent Claim
41 words
The method of claim 5, 6, or 10 wherein at least a portion of said polysilicon layer is patterned by reactive ion etching said polysilicon layer in a plasma which comprises active etchant radicals that include chlorine constituents as etching species.
Claim 18
Dependent Claim
19 words
The method of claim 16 wherein said plasma is established in a gaseous atmosphere which includes Cl 2 gas.
Claim 19
Dependent Claim
81 words
The method of claim 17 wherein said reactive ion etching is accomplished by mounting said device on a driven electrode of a reactive ion etching apparatus, flowing said Cl 2 gas into said apparatus at a flow rate in the range 5 to 100 standard cubic centimeters per minute, maintaining a pressure of said gaseous atmosphere within said apparatus in the range 2 to 60 millitorr, and maintaining the power density in the range 0.05 to 1.0 watts per square centimeter.
Claim 20
Dependent Claim
46 words
The method of claim 18 wherein said flow rate is in the range 10 to 25 standard cubic centimeters per minute, said pressure is in the range 4 to 20 millitorr, and said power density is in the range 0.15 to 0.4 watts per square centimeter.
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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) | 1987-09-18 | 1988-03-19 | 1988-09-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-09-18 | 1992-03-19 | 1992-09-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-09-18 | 1996-03-19 | 1996-09-18 | $7700.00 | Window Closed / Lapsed |