US4519870A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for producing a single crystal
Assignee: NGK Insulators Ltd
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Filing: 1982-11-19
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Granted: 1985-05-28
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Expires: 2002-11-19
Abstract
Abstract A single crystal is produced by contacting a polycrystal showing a discontinuous crystal grain growth at a temperature not lower than T° C. to a seed single crystal having substantially the same crystal structure as the polycrystal and heating the contacted crystals at a temperature (t° C.) lower than the temperature T° C. to cause a solid phase reaction at an interface between microcrystal grains composing the polycrystal and the seed single crystal, whereby the microcrystal grains in the polycrystal are integrated to the seed single crystal to grow the single crystal.
Inventors
- 👤 Soichiro Matsuzawa
- 👤 Syunzo Mase
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 05:07
CPC Classifications
C; C30; C30B; C30B1/00; C30B1/02; C30B29/00; C30B29/10; C30B29/16; C30B29/22; C30B29/26
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
126 words
In a method for producing a single crystal which comprises contacting a seed single crystal to a fine grain polycrystal body having substantially the same crystal structure as the seed single crystal, and heating the contacted crystals to grow the single crystal towards the polycrystal, the improvement comprising the steps of: (a) using a polycrystal having the property which causes a discontinuous crystal grain growth in the course of heating, (b) heating the contacted crystals to grow the single crystal at a temperature (t°C.) which is lower than the temperature (T°C.) at which the discontinuous crystal grain growth is caused in the polycrystal, and (c) integrating a thickness of at least 0.25 mm of the polycrystal to the seed single crystal to grow the single crystal.
Claim 2
Dependent Claim
126 words
In a method for producing a single crystal which comprises contacting a seed single crystal to a fine grain polycrystal body having substantially the same crystal structure as the seed single crystal, and heating the contacted crystals to grow the single crystal towards the polycrystal, the improvement comprising the steps of: (a) using a polycrystal having the property which causes a discontinuous crystal grain growth in the course of heating, (b) heating the contacted crystals to grow the single crystal at a temperature (t°C.) which is lower than the temperature (T°C.) at which the discontinuous crystal grain growth is caused in the polycrystal, and (c) integrating a thickness of at least 0.25 mm of the polycrystal to the seed single crystal to grow the single crystal.
Claim 3
Dependent Claim
22 words
The method according to claim 1 characterized in that the entire mass of seed single crystal and polycrystal is heated in bulk.
Claim 4
Dependent Claim
34 words
A method for producing a single crystal according to claim 1, wherein a thickness of 0.25 to 5 mm of the polycrystal is integrated to the seed single crystal to grow the single crystal.
Claim 5
Dependent Claim
34 words
A method for producing a single crystal according to claim 1 wherein a thickness of 3 to 5 mm of the polycrystal is integrated to the seed single crystal to grow the single crystal.
Claim 6
Dependent Claim
28 words
A method as claimed in claim 2, wherein the seed single crystal is one crystal selected from the group consisting of cubic system of ferrite, garnet and spinel.
Claim 7
Dependent Claim
14 words
A method as claimed in claim 5, wherein the seed single crystal is ferrite.
Claim 8
Dependent Claim
83 words
A method as claimed in claim 6, wherein the seed single crystal ferrite is contacted to the polycrystal ferrite in the given crystallographic orientation and the heating is effected at a temperature being 1,200° C.≦t≦1,450° C., whereby the seed single crystal ferrite is grown toward the polycrystal ferrite to convert a part of the polycrystal ferrite into the single crystal in substantially the same crystallographic orientation as the seed single crystal ferrite, after which the original seed single crystal ferrite portion is removed.
Claim 9
Dependent Claim
16 words
A method as claimed in claim 2, wherein the heating temperature (t°C.) is as follows: T-100≦t<T.
Claim 10
Dependent Claim
16 words
A method as claimed in claim 4, wherein the heating temperature (t°C.) is as follows: T-100≦t≦T.
Claim 11
Dependent Claim
16 words
A method as claimed in claim 6, wherein the heating temperature (t°C.) is as follows: T-100≦t<T.
Claim 12
Dependent Claim
16 words
A method as claimed in claim 5, wherein the heating temperature (t°C.) is as follows: T-100≦t<T.
Claim 13
Dependent Claim
16 words
A method as claimed in claim 7, wherein the heating temperature (t°C.) is as follows: T-100≦t<T.
Claim 14
Dependent Claim
31 words
A method as claimed in claim 1, wherein when a given thickness portion of the polycrystal contacting to the seed single crystal is converted into single crystal, the heating is stopped.
Claim 15
Dependent Claim
28 words
A method as claimed in claim 1, wherein the seed single crystal is one crystal selected from the group consisting of cubic system of ferrite, garnet and spinel.
Claim 16
Dependent Claim
14 words
A method as claimed in claim 14, wherein the seed single crystal is ferrite.
Claim 17
Dependent Claim
84 words
A method as claimed in claim 15, wherein the seed single crystal ferrite is contacted to the polycrystal ferrite in the given crystallographic orientation and the heating is effected at a temperature t°C. being 1,200° C.≦t≦1,450° C., whereby the seed single crystal ferrite is grown toward the polycrystal ferrite to convert a part of the polycrystal ferrite into the single crystal in substantially the same crystallographic orientation as the seed single crystal ferrite, after which the original seed single crystal ferrite portion is removed.
Claim 18
Dependent Claim
16 words
A method as claimed in claim 1 wherein the heating temperature (t°C.) is as follows: T-100≦t<T.
References Cited (Backward Citations)
US2992903A
Cited
US3160521A
Cited
US3350240A
Cited
US3348962A
Cited
US3429831A
Cited
US3655439A
Cited
US3585088A
Cited
US3694269A
Cited
US4046618A
Cited
US4057458A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-05-27 | 1988-11-26 | 1989-05-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-05-27 | 1992-11-26 | 1993-05-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-05-27 | 1996-11-26 | 1997-05-28 | $7700.00 | Window Closed / Lapsed |