Patent US905200A successfully refreshed from Google Patents.
Patent US4356152A successfully refreshed from Google Patents.
US4356152A
Expired / Lapsed
US
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Silicon melting crucible
Assignee: Intersil Corp
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Filing: 1981-03-13
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Granted: 1982-10-26
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Expires: 2001-03-13
Abstract
Abstract An improved liner for crucibles and dies used to melt silicon comprising one or more sheets of graphite each of which has on at least the surface facing the silicon melt a layer of silicon nitride or silicon oxynitride.
Inventors
- 👤 Samuel Berkman
- 👤 Michael T. Duffy
- 👤 Harold E. Temple
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 18:46
CPC Classifications
F; F24; F24D; F24D1/00; C; C30; C30B; C30B15/00; C30B15/10; C30B35/00; C30B35/002; F27; F27B; F27B14/00; F27B14/08; F27B14/10; Y; Y10; Y10S; Y10S117/00; Y10S117/90; Y10S117/91; Y10T; Y10T117/00; Y10T117/10; Y10T117/1024; Y10T117/1032; Y10T117/1036; Y10T117/1044; Y10T428/00; Y10T428/26; Y10T428/263; Y10T428/30
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
70 words
In a crucible for forming a silicon melt, the improvement comprising providing on all internal surfaces of said crucible which might contact the molten silicon a protective lining comprising one or more thin, flexible sheets of graphite each of which has on at least the surface facing the molten silicon a layer of silicon nitride or silicon oxynitride and at least one of which has said layer on both surfaces.
Claim 2
Dependent Claim
70 words
In a crucible for forming a silicon melt, the improvement comprising providing on all internal surfaces of said crucible which might contact the molten silicon a protective lining comprising one or more thin, flexible sheets of graphite each of which has on at least the surface facing the molten silicon a layer of silicon nitride or silicon oxynitride and at least one of which has said layer on both surfaces.
Claim 3
Dependent Claim
27 words
The improved crucible in accordance with claim 1, wherein each of said sheets of graphite has a thickness of from about 2 mils to about 12 mils.
Claim 4
Dependent Claim
22 words
The improved crucible in accordance with claim 2, wherein each of said sheets of graphite has a thickness of about 3 mils.
Claim 5
Dependent Claim
21 words
The improved crucible in accordance with claim 1, wherein said layer is from about 1/20 mil to about 1 mil thick.
Claim 6
Dependent Claim
21 words
The improved crucible in accordance with claim 4, wherein said layer is from about 1/20 mil to about 1/2 mil thick.
Claim 7
Dependent Claim
29 words
The improved crucible in accordance with claim 1, wherein said lining is comprised of 2 sheets of graphite at least one of which has said layer on both surfaces.
Claim 8
Dependent Claim
24 words
The improved crucible in accordance with claim 1, wherein said lining has a total thickness of from about 3 mils to about 12 mils.
Claim 9
Dependent Claim
24 words
The improved crucible in accordance with claim 7, wherein said lining has a total thickness of from about 6 mils to about 7 mils.
Claim 10
Dependent Claim
37 words
The improved crucible in accordance with claim 1, wherein said crucible additionally includes die means for growing silicon in sheet or ribbon form, the internal surfaces of said die means also being provided with said protective lining.
Claim 11
Dependent Claim
18 words
The improved crucible in accordance with claim 1, wherein the improvement additionally comprises forming said crucible of mullite.
Claim 12
Dependent Claim
22 words
The improved crucible in accordance with claim 9, wherein the improvement additionally comprises forming said die means and said crucible of mullite.
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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) | 1985-10-25 | 1986-04-26 | 1986-10-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-10-25 | 1990-04-26 | 1990-10-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-10-25 | 1994-04-26 | 1994-10-26 | $7700.00 | Window Closed / Lapsed |