US4528061A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for manufacturing boron-doped gallium arsenide single crystal
Assignee: Sumitomo Electric Industries Ltd
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Filing: 1983-04-15
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Granted: 1985-07-09
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Expires: 2003-04-15
Abstract
Abstract A process for manufacturing boron-doped GaAs single crystals which comprises preparing a mixture of boron, gallium and arsenic covered by a liquid B 2 O 3 encapsulant, melting the mixture, pulling up boron-doped GaAs crystals from the mixture melts in accordance with the LEC method, crushing those crystals into small pieces after removing the seed end therefrom, remelting those pieces in the presence of B 2 O 3 , and pulling up single crystals from the mixture melts in accordance with the LEC method.
Inventors
- 👤 Shintaro Miyazawa
- 👤 Yasushi Nanishi
- 👤 Kohji Tada
- 👤 Akihisa Kawasaki
- 👤 Toshihiro Kotani
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 19:55
CPC Classifications
C; C30; C30B; C30B27/00; C30B27/02; C30B29/00; C30B29/10; C30B29/40; C30B29/42
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
101 words
A process for manufacturing a boron-doped GaAs single crystal containing a large quantity of boron, comprising: preparing a mixture of boron, gallium and arsenic covered by a liquid B 2 O 3 encapsulant; melting the mixture; pulling up a boron-doped GaAs body from the melted mixture in accordance with the LEC (Liquid Encapsulated Czochralski) method in which a seed is employed; crushing the body into small pieces after removing the seed end therefrom; remelting the pieces in the presence of B 2 O 3 ; and pulling up a single crystal from the remelted pieces in accordance with the LEC method.
Claim 2
Dependent Claim
101 words
A process for manufacturing a boron-doped GaAs single crystal containing a large quantity of boron, comprising: preparing a mixture of boron, gallium and arsenic covered by a liquid B 2 O 3 encapsulant; melting the mixture; pulling up a boron-doped GaAs body from the melted mixture in accordance with the LEC (Liquid Encapsulated Czochralski) method in which a seed is employed; crushing the body into small pieces after removing the seed end therefrom; remelting the pieces in the presence of B 2 O 3 ; and pulling up a single crystal from the remelted pieces in accordance with the LEC method.
Claim 3
Dependent Claim
14 words
Process as set forth in claim 1, wherein the body is a polycrystalline body.
Claim 4
Dependent Claim
17 words
A process as set forth in claim 1, further including incorporating additional boron when remelting the pieces.
Claim 5
Dependent Claim
33 words
A process as set forth in claim 3, wherein the gallium and arsenic are of the 6-nine grade (99.9999%) in purity, and the B 2 O 3 is of the 5-nine grade (99.999%).
Claim 6
Dependent Claim
25 words
A process as set forth in claim 4, wherein the boron is in the form of shots having a diameter of 1 to 2 mm.
Claim 7
Dependent Claim
25 words
A process as set forth in claim 4, wherein the B 2 O 3 has a water content of less than 300 ppm by weight.
Claim 8
Dependent Claim
25 words
A process as set forth in claim 4, wherein the B 2 O 3 has a water content of higher than 600 ppm by weight.
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) | 1988-07-08 | 1989-01-07 | 1989-07-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-07-08 | 1993-01-07 | 1993-07-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-07-08 | 1997-01-07 | 1997-07-09 | $7700.00 | Window Closed / Lapsed |