Patent US3867496A successfully refreshed from Google Patents.
US3867496A
Expired / Lapsed
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Method and apparatus for producing fine-grated polycrystalline bodies
Assignee: Tyco International Ltd
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Filing: 1972-06-08
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Granted: 1975-02-18
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Expires: 1992-06-08
Abstract
Abstract Fine-grained polycrystalline semi-conductor bodies of chalcogenides are produced by directional solidification under the influence of sonic vibrations in the range of about 500 to about 10,000 Hz. The charge material is disposed in a container that is secured within a heat susceptor assembly and is melted inductively by operation of RF heating means positioned proximate to the susceptor assembly. The susceptor assembly is mechanically coupled to an electrodynamic vibrator unit so that vibrations produced by the vibrator unit are transmitted to the melt by way of the susceptor assembly and the walls of the melt container. Solidification is achieved by progressively reducing the temperature of the melt while maintaining a vertical temperature gradient across the melt container, the gradient being such that solidification proceeds upwardly in the melt.
Inventors
- 👤 Abraham I Mlavsky
- 👤 Herbert E Bates
- 👤 Bernard Siegel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 18:30
CPC Classifications
C; C30; C30B; C30B11/00; C01; C01B; C01B19/00; C01B19/007; C30B29/00; C30B29/10; C30B29/46; C30B29/48; C30B29/60; C30B29/605
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
173 words
METHOD OF PRODUCING A DENSE, HOMOGENEOUS POLYCRYSTALLINE BODY OF A SELECTED CHALCOGENIDE MATERIAL HAVING A CROSSSECTIONAL DIMENSION OF AT LEAST 2 INCHES, SAID METHOD COMPRISING DISPOSING A CHARGE OF SAID MATERIAL IN THE SOLID STATE IN A SEALED HEAT-RESISTANT CONTAINER, MOUNTING SAID CONTAINER WITHIN A HEAT SUSCEPTOR SO THAT SAID CONTAINER IS ENCLOSED BY SAID SUSCEPTOR AND SO THAT SAID SUSCEPTOR AND CONTAINER WILL MOVE AS A UNIT, ELECTRICALLY HEATING SAID SUSCEPTOR AND THEREBY MELTING SAID CHARGE AND VIBRATING SAID SUSCEPTOR AND CONTAINER AND THEREBY THE RESULTING MELT AT A SONIC FREQUENCY IN THE RANGE OF ABOUT 500-10,000 HZ, ESTABLISHING A THERMAL GRADIENT ACROSS THE SUSCEPTOR SO THAT THE UPPER END OF THE MELT IS HOTTER THAN THE BOTTOM END THEREOF AND THE THERMAL GRADIENT IS ABOUT 30*C PER CENTIMETER OF MELT HEIGHT, AND DIRECTIONALLY COOLING SAID SUSCEPTOR AND CONTAINER AS THEY ARE BEING VIBRATED SO AS TO CAUSE THE MELT TO SOLIDIFY DIRECTIONALLY WITH SOLIDIFICATION OF SAID MELT COMMENCING AT THE BOTTOM END THEREOF AND PROGRESSING UPWARDLY TO THE TOP END THEREOF.
Claim 2
Dependent Claim
173 words
METHOD OF PRODUCING A DENSE, HOMOGENEOUS POLYCRYSTALLINE BODY OF A SELECTED CHALCOGENIDE MATERIAL HAVING A CROSSSECTIONAL DIMENSION OF AT LEAST 2 INCHES, SAID METHOD COMPRISING DISPOSING A CHARGE OF SAID MATERIAL IN THE SOLID STATE IN A SEALED HEAT-RESISTANT CONTAINER, MOUNTING SAID CONTAINER WITHIN A HEAT SUSCEPTOR SO THAT SAID CONTAINER IS ENCLOSED BY SAID SUSCEPTOR AND SO THAT SAID SUSCEPTOR AND CONTAINER WILL MOVE AS A UNIT, ELECTRICALLY HEATING SAID SUSCEPTOR AND THEREBY MELTING SAID CHARGE AND VIBRATING SAID SUSCEPTOR AND CONTAINER AND THEREBY THE RESULTING MELT AT A SONIC FREQUENCY IN THE RANGE OF ABOUT 500-10,000 HZ, ESTABLISHING A THERMAL GRADIENT ACROSS THE SUSCEPTOR SO THAT THE UPPER END OF THE MELT IS HOTTER THAN THE BOTTOM END THEREOF AND THE THERMAL GRADIENT IS ABOUT 30*C PER CENTIMETER OF MELT HEIGHT, AND DIRECTIONALLY COOLING SAID SUSCEPTOR AND CONTAINER AS THEY ARE BEING VIBRATED SO AS TO CAUSE THE MELT TO SOLIDIFY DIRECTIONALLY WITH SOLIDIFICATION OF SAID MELT COMMENCING AT THE BOTTOM END THEREOF AND PROGRESSING UPWARDLY TO THE TOP END THEREOF.
Claim 3
Dependent Claim
11 words
Method according to claim 1 wherein said material is a telluride.
Claim 4
Dependent Claim
22 words
Method according to claim 1 wherein said melt is directionally cooled at a rate in the order of 0.1* C per minute.
Claim 5
Dependent Claim
18 words
Method according to claim 1 wherein said cooling is achieved by lowering the rate of heating said susceptor.
Claim 6
Dependent Claim
32 words
Method according to claim 1 wherein said cooling is achieved at least in part by circulating a cooling fluid through a heat exchanger positioned proximate to the bottom end of said container.
Claim 7
Dependent Claim
54 words
Method according to claim 1 wherein said charge is melted by operation of a first and second heater means located adjacent to the top and bottom ends respectively of said container, and further wherein said heater means are operated so as to establish and maintain said thermal gradient and to effect said directional cooling.
Claim 8
Dependent Claim
21 words
Method according to claim 1 wherein said charge is melted by operation of RF heater means positioned adjacent to said susceptor.
Claim 9
Dependent Claim
21 words
Method according to claim 7 wherein said melt is cooled by progressively reducing the power input to said RF heater means.
Claim 10
Dependent Claim
21 words
Method according to claim 1 wherein said susceptor and container are vibrated at an acceleration level in the range of 2-15g.
Claim 11
Dependent Claim
18 words
Method according to claim 1 wherein said melt is vibrated at a frequency in the range of 2,000-4,000Hz.
Claim 12
Dependent Claim
19 words
Method according to claim 1 wherein said material consists of PbTe, CdTe or a mixture of PbTe and SnTe.
References Cited (Backward Citations)
US2384215A
Cited
US2911678A
Cited
US3413392A
Cited
US3447587A
Cited
US3608050A
Cited
US3717427A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-02-17 | 1978-08-19 | 1979-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-17 | 1982-08-19 | 1983-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-17 | 1986-08-19 | 1987-02-18 | $7700.00 | Window Closed / Lapsed |