US4409195A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Purification of silicon source materials
Assignee: Motorola Solutions Inc
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Filing: 1982-08-19
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Granted: 1983-10-11
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Expires: 2002-08-19
Abstract
Abstract A process is disclosed for the purification of trichlorosilane and other silicon source materials. Trace impurities of boron and phosphorous are removed from trichlorosilane or dichlorosilane by reacting small amounts of oxygen with the trichlorosilane or dichlorosilane at a temperature between about 60° C. and 300° C. The oxygen reacts with the Si--H bond in HSiCl 3 or H 2 SiCl 2 to form a "SiOH" species which in turn complexes impurities such as BCl 3 or PCl 3 present in the chlorosilane. Purification of the chlorosilane is then easily accomplished during a subsequent distillation step which separates the purified chlorosilane from the less volatile complexed boron or phosphorous compounds.
Inventors
- 👤 Robert D. Darnell
- 👤 William M. Ingle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:26
CPC Classifications
C; C01; C01B; C01B33/00; C01B33/08; C01B33/107; C01B33/10778; C01B33/10794; C01B33/02; C01B33/021; C01B33/027; C01B33/035; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/582
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
77 words
A process for removing dopant impurity including one or more of boron, phosphorous, arsenic and aluminum in the form of chlorides, hydrides, or intermediate compounds containing both hydrogen and chlorine from a silicon source material including trichlorosilane or dichlorosilane which comprises the steps of: heating said material in gaseous form to a temperature between about 170° C. and about 500° C. with oxygen to form impurity containing siloxane complexes; and separating said complexes from said source material.
Claim 2
Dependent Claim
77 words
A process for removing dopant impurity including one or more of boron, phosphorous, arsenic and aluminum in the form of chlorides, hydrides, or intermediate compounds containing both hydrogen and chlorine from a silicon source material including trichlorosilane or dichlorosilane which comprises the steps of: heating said material in gaseous form to a temperature between about 170° C. and about 500° C. with oxygen to form impurity containing siloxane complexes; and separating said complexes from said source material.
Claim 3
Dependent Claim
15 words
The process of claim 1 wherein said silicon source material comprises trichlorosilane and silicon tetrachloride.
Claim 4
Dependent Claim
14 words
The process of claim 1 wherein said silicon source material comprises trichlorosilane and dichlorosilane.
Claim 5
Dependent Claim
26 words
The process of claim 1 wherein said oxygen is present in a ratio with said trichlorosilane or dichlorosilane of about 0.01 to about 1.0 mole percent.
Claim 6
Dependent Claim
17 words
The process of claim 1 wherein said temperature is between about 170° C. and about 300° C.
Claim 7
Dependent Claim
12 words
The process of claim 5 wherein said temperature is about 200° C.
Claim 8
Dependent Claim
75 words
A process for removing dopant impurity including one or more of boron, phosphorous, arsenic, and aluminum in the form of chlorides, hydrides or intermediate compounds containing both hydrogen and chlorine from a silicon source material including dichlorosilane which comprises the steps of: heating said material in gaseous form to a temperature between about 60° C. and about 300° C. with oxygen to form impurity containing siloxane complexes; and separating said complexes from said source material.
Claim 9
Dependent Claim
75 words
A process for removing dopant impurity including one or more of boron, phosphorous, arsenic, and aluminum in the form of chlorides, hydrides or intermediate compounds containing both hydrogen and chlorine from a silicon source material including dichlorosilane which comprises the steps of: heating said material in gaseous form to a temperature between about 60° C. and about 300° C. with oxygen to form impurity containing siloxane complexes; and separating said complexes from said source material.
Claim 10
Dependent Claim
15 words
The process of claim 7 wherein said silicon source material comprises dichlorosilane and silicon tetrachloride.
Claim 11
Dependent Claim
14 words
The process of claim 7 wherein said silicon source material comprises trichlorosilane and dichlorosilane.
Claim 12
Dependent Claim
24 words
The process of claim 7 wherein said oxygen is present in a ratio with said dichlorosilane of about 0.01 to about 1.0 mole percent.
Claim 13
Dependent Claim
17 words
The process of claim 7 wherein said temperature is between about 170° C. and about 300° C.
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) | 1986-10-10 | 1987-04-11 | 1987-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-10-10 | 1991-04-11 | 1991-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-10-10 | 1995-04-11 | 1995-10-11 | $7700.00 | Window Closed / Lapsed |