US4836997A
Expired / Lapsed
US
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Plasma production of trichorosilane, SiHCl3
Assignee: Rhone Poulenc Specialites Chimiques
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Filing: 1983-07-25
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Granted: 1989-06-06
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Expires: 2003-07-25
Abstract
Abstract Trichlorosilane, SiHCl 3 , is facilely prepared by (i) thermally reducing silicon tetrachloride, SiCl 4 , with hydrogen to produce reaction admixture comprising SiHCl 3 and hydrochloric acid, said thermal reduction being carried out in a thermal plasma while tempering the reaction medium with a cooling gas, (ii) reacting said step (i) reaction admixture with elemental silicon at a temperature of from about 250° to 350° C. to produce SiHCl 3 and hydrogen therefrom, and thence (iii) separating (iiia) the plasma-creating, hydrogen and cooling gases, and (iiib) product silicon chlorides therefrom.
Inventors
- 👤 Jean-Luc Lepage
- 👤 Gerard Simon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 01:34
CPC Classifications
C; C01; C01B; C01B33/00; C01B33/08; C01B33/107; C01B33/1071; Y; Y10; Y10S; Y10S423/00; Y10S423/09; Y10S423/10
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
96 words
A process for the preparation of trichlorosilane, SiHCl 3 , which comprises (i) thermally reducing silicon tetrachloride, SiCl 4 , with hydrogen to produce a reaction admixture comprising SiHCl 3 and hydrochloric acid, said thermal reduction being carried out in a thermal plasma while tempering the reaction medium with a cooling gas, (ii) reacting said step (i) reaction admixture with elemental silicon at a temperature of from about 250° to 350° C. to produce SiHCl 3 and hydrogen therefrom, and thence (iii) separating (iiia) the plasma-creating, hydrogen and cooling gases, and (iiib) product silicon chlorides therefrom.
Claim 2
Dependent Claim
96 words
A process for the preparation of trichlorosilane, SiHCl 3 , which comprises (i) thermally reducing silicon tetrachloride, SiCl 4 , with hydrogen to produce a reaction admixture comprising SiHCl 3 and hydrochloric acid, said thermal reduction being carried out in a thermal plasma while tempering the reaction medium with a cooling gas, (ii) reacting said step (i) reaction admixture with elemental silicon at a temperature of from about 250° to 350° C. to produce SiHCl 3 and hydrogen therefrom, and thence (iii) separating (iiia) the plasma-creating, hydrogen and cooling gases, and (iiib) product silicon chlorides therefrom.
Claim 3
Dependent Claim
22 words
The process as defined by claim 1, said step (ii) being carried out in the presence of catalytically effective amounts of copper.
Claim 4
Dependent Claim
14 words
The process as defined by claim 2, further comprising recycling of said gases (iiia).
Claim 5
Dependent Claim
14 words
The process as defined by claim 2, said cooling gas comprising the plasma-creating gas.
Claim 6
Dependent Claim
14 words
The process as defined by claim 2, said cooling gas comprising silicon tetrachloride vapors.
Claim 7
Dependent Claim
14 words
The process as defined by claim 2, said cooling gas comprising an inert gas.
Claim 8
Dependent Claim
16 words
The process as defined by claim 1, further comprising reducing product SiHCl 3 to elemental silicon.
Claim 9
Dependent Claim
23 words
The process as defined by claim 1, the hydrochloric acid produced in the step (i) being essentially completely converted in said step (ii).
Claim 10
Dependent Claim
22 words
The process as defined by claim 7, said product (iiib) being purified prior to reduction of the SiHCl 3 to elemental silicon.
Claim 11
Dependent Claim
102 words
A process for the preparation of trichlorosilane, SiHCl 3 , which comprises (i) thermally reducing silicon tetrachloride, SiCl 4 , with hydrogen to produce a reaction admixture comprising SiHCl 3 and hydrochloric acid, said thermal reduction being carried out in a thermal plasma while tempering the reaction medium by injecting with a cooling gas directly into said medium, (ii) reacting said step (i) reaction admixture with elemental silicon at a temperature of from about 250° to 350° C. to produce SiHCl 3 and hydrogen therefrom, and thence (iii) separating (iiia) the plasma-creating, hydrogen and cooling gases, and (iiib) product silicon chlorides therefrom.
Claim 12
Dependent Claim
102 words
A process for the preparation of trichlorosilane, SiHCl 3 , which comprises (i) thermally reducing silicon tetrachloride, SiCl 4 , with hydrogen to produce a reaction admixture comprising SiHCl 3 and hydrochloric acid, said thermal reduction being carried out in a thermal plasma while tempering the reaction medium by injecting with a cooling gas directly into said medium, (ii) reacting said step (i) reaction admixture with elemental silicon at a temperature of from about 250° to 350° C. to produce SiHCl 3 and hydrogen therefrom, and thence (iii) separating (iiia) the plasma-creating, hydrogen and cooling gases, and (iiib) product silicon chlorides therefrom.
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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) | 1992-06-05 | 1992-12-05 | 1993-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-06-05 | 1996-12-05 | 1997-06-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-06-05 | 2000-12-05 | 2001-06-06 | $7700.00 | Window Closed / Lapsed |