Patent US3984267A successfully refreshed from Google Patents.
US3984267A
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US
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Process and apparatus for diffusion of semiconductor materials
Assignee: Monsanto Co
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Filing: 1974-07-26
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Granted: 1976-10-05
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Expires: 1994-07-26
Abstract
Abstract Apparatus for semi-sealed diffusion of semiconductor materials includes a quartz tube with a quartz stopper at one end to facilitate the loading and unloading of semiconductor materials, the other end of the quartz tube having an inlet passage with a quartz stopcock. The stopper includes quartz pressure release valve.
Inventors
- 👤 Magnus George Craford
- 👤 Paul Michael Garavaglia
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 08:49
CPC Classifications
C; C30; C30B; C30B31/00; C30B31/06; C30B31/10
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
160 words
A process for introducing dopants by diffusion into semiconductor materials, said process comprising placing semiconductor material in an ampoule with a dopant source, closing said ampoule, sealing the ampoule but providing a pressure relief valve for the ampoule at one end thereof, purging the interior of the ampoule by admitting an inert gas to the ampoule through a valved passage at the opposite end of said ampoule and causing said inert gas to flow through said ampoule and out said relief valve, and heating the ampoule for a predetermined period of time to diffuse the dopant into semiconductor material, permitting gas pressure within said ampoule to be vented from said ampoule through said relief valve during diffusion while substantially preventing gas from entering said ampoule, said heating the ampoule being carried out in a diffusion furnace while supplying an inert gas to the diffusion furnace so as to surround said ampoule by the inert gas supplied to the diffusion furnace.
Claim 2
Dependent Claim
160 words
A process for introducing dopants by diffusion into semiconductor materials, said process comprising placing semiconductor material in an ampoule with a dopant source, closing said ampoule, sealing the ampoule but providing a pressure relief valve for the ampoule at one end thereof, purging the interior of the ampoule by admitting an inert gas to the ampoule through a valved passage at the opposite end of said ampoule and causing said inert gas to flow through said ampoule and out said relief valve, and heating the ampoule for a predetermined period of time to diffuse the dopant into semiconductor material, permitting gas pressure within said ampoule to be vented from said ampoule through said relief valve during diffusion while substantially preventing gas from entering said ampoule, said heating the ampoule being carried out in a diffusion furnace while supplying an inert gas to the diffusion furnace so as to surround said ampoule by the inert gas supplied to the diffusion furnace.
Claim 3
Dependent Claim
47 words
A process as set forth in claim 1 wherein said semiconductor material is constituted by at least one wafer, said process further comprising the step of first coating said wafer with an oxide layer, and said process including the step of stripping said oxide layer following diffusion.
Claim 4
Dependent Claim
18 words
A process as set forth in claim 2 wherein said oxide layer is constituted by SiO 2 .
Claim 5
Dependent Claim
18 words
A process as set forth in claim 3 wherein said SiO 2 is deposited by chemical vapor deposition.
Claim 6
Dependent Claim
20 words
A process as set forth in claim 3 wherein said SiO 2 is deposited by spinning silicafilm onto said wafer,
Claim 7
Dependent Claim
49 words
A process as set forth in claim 2 wherein said heating the ampoule is carried out in a diffusion furnace and further comprising the step of supplying an inert gas to the diffusion furnace so as to surround said ampoule by the inert gas supplied to the diffusion furnace.
Claim 8
Dependent Claim
17 words
A process as set forth in claim 6 wherein said semiconductor material is a III-V compound semiconductor.
Claim 9
Dependent Claim
17 words
A process as set forth in claim 7 wherein said III-V compound semiconductor is GaAsP or GaP.
Claim 10
Dependent Claim
16 words
A process as set forth in claim 7 wherein said dopant source is a zinc source.
Claim 11
Dependent Claim
16 words
A process as set forth in claim 9 wherein said zinc source is ZnAs 2 .
References Cited (Backward Citations)
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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) | 1979-10-05 | 1980-04-05 | 1980-10-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-10-05 | 1984-04-05 | 1984-10-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-10-05 | 1988-04-05 | 1988-10-05 | $7700.00 | Window Closed / Lapsed |