US5055246A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of forming high purity metal silicides targets for sputtering
Assignee: LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
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Filing: 1991-01-22
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Granted: 1991-10-08
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Expires: 2011-01-22
Abstract
Abstract The invention relates to a process of making a high purity silicide target comprising the steps of providing a substrate in a CVD enclosure, evacuating said enclosure up to a pressure P1 which is at least equal to or smaller than 5×10 -5 Torr, heating the substrate at a temperature T1, which is at least equal to or greater than 20° C., injecting in said enclosure a refractory metal halide MXm having a purity, as far as metallic impurities are concerned, greater than 5N (99,999%) and a silicon hydride having a purity, as far as metallic impurities are concerned, greater than 6N (99,9999%) setting the pressure in the enclosure between about 0.01 Torr and the atmospheric pressure while maintaining the temperature in the CVD enclosure between about 20° C., growing a refractory metal silicide layer on the substrate to make a target having a purity, as far as metallic impurities are concerned, greater than 5N (99,99%), maintaining the temperature in the enclosure during said growing step at a value T2 which is not greater than T1, then withdrawing the target from said CVD enclosure.
Inventors
- 👤 Pierre Jalby
- 👤 Pierre Claverie
- 👤 Frederic Rotman
- 👤 Masao Kimura
- 👤 Jean-Marie Friedt
- 👤 Juichi Arai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:24
CPC Classifications
C; C23; C23C; C23C14/00; C23C14/22; C23C14/34; C23C14/3407; C23C14/3414; C23C16/00; C23C16/22; C23C16/30; C23C16/42
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
184 words
A method to manufacture a high purity silicide target comprising the steps of providing a substrate in a CVD enclosure, evacuating said enclosure up to a pressure P1 which is at least equal to or smaller than 5×10 -5 Torr, heating the substrate at a temperature T1, which is at least equal to or greater than 20° C., injecting in said enclosure a refractory metal halide MXm having a purity, as far as metallic impurities are concerned, greater than 5N (99,999%) and a silicon hydride having a purity, as far as metallic impurities are concerned, greater than 6N (99,9999%) setting the pressure in the enclosure between about 0.01 Torr and the atmospheric pressure while maintaining the temperature in the CVD enclosure between about 20° C. and about 800° C., growing a refractory metal silicide layer on the substrate to make a target having a purity, as far as metallic impurities are concerned, greater than 5N (99,999%), maintaining the temperature in the enclosure during said growing step at a value T2 which is not greater than T1, then withdrawing the target from said CVD enclosure.
Claim 2
Independent Claim
184 words
A method to manufacture a high purity silicide target comprising the steps of providing a substrate in a CVD enclosure, evacuating said enclosure up to a pressure P1 which is at least equal to or smaller than 5×10 -5 Torr, heating the substrate at a temperature T1, which is at least equal to or greater than 20° C., injecting in said enclosure a refractory metal halide MXm having a purity, as far as metallic impurities are concerned, greater than 5N (99,999%) and a silicon hydride having a purity, as far as metallic impurities are concerned, greater than 6N (99,9999%) setting the pressure in the enclosure between about 0.01 Torr and the atmospheric pressure while maintaining the temperature in the CVD enclosure between about 20° C. and about 800° C., growing a refractory metal silicide layer on the substrate to make a target having a purity, as far as metallic impurities are concerned, greater than 5N (99,999%), maintaining the temperature in the enclosure during said growing step at a value T2 which is not greater than T1, then withdrawing the target from said CVD enclosure.
Claim 3
Dependent Claim
33 words
A method according to claim 1, further comprising the steps of, after providing the substrate in the enclosure, evacuating the enclosure at a pressure P2<P1 while heating the substrate at a temperature T2>T1.
Claim 4
Dependent Claim
17 words
A method according to claim 1, wherein the substrate is separated from the refractory metal silicide layer.
Claim 5
Dependent Claim
25 words
A method according to claim 1, wherein the metal of said metal silicide is selected from the group consisting of Tungsten, Molybdenum, Tantalum and Titanium.
Claim 6
Dependent Claim
16 words
A method according to claim 1, wherein said metal halide gas is a fluoride metal gas.
Claim 7
Dependent Claim
29 words
A method according to claim 5, wherein said fluoride gas is selected from the group consisting of WF 6 , MoF 6 , TaF 5 and TiF 4 .
Claim 8
Dependent Claim
16 words
A method according to claim 1, wherein said metal halide gas is a metal chloride gas.
Claim 9
Dependent Claim
30 words
A method according to claim 7, wherein said metal chloride gas is selected from the group consisting of WCl 6 , MoCl 6 , TaCl 5 and TiCl 4 .
Claim 10
Dependent Claim
24 words
A method according to claim 1, wherein said Silicon hydride gas is a gas having the chemical formula: Si n H 2n+2 with n=1,2,3.
Claim 11
Dependent Claim
35 words
A method according to claim 1, wherein said metal halide gas is WF 6 or MoF 6 gas, said Silicon Hydride gas is silane (SiH 4 ), and said temperature is at least 150° C.
Claim 12
Dependent Claim
20 words
A method according to claim 1, wherein the substrate is selected from the group consisting of copper and its alloys.
Claim 13
Dependent Claim
24 words
A method according to claim 11, where in said substrate is dissolved with an acidic medium after removal of the target from the enclosure.
References Cited (Backward Citations)
US4851295A
Cited
US4750932A
Cited
JPS6260864A
Cited
US4938798A
Cited
JPS63227771A
Cited
JPS6439374A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-10-07 | 1995-04-08 | 1995-10-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-10-07 | 1999-04-08 | 1999-10-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-10-07 | 2003-04-08 | 2003-10-08 | $7700.00 | Window Closed / Lapsed |