US4013501A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Growth of neodymium doped yttrium aluminum garnet crystals
Assignee: AT&T Inc
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Filing: 1976-05-27
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Granted: 1977-03-22
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Expires: 1996-05-27
Abstract
Abstract A method is disclosed for growing neodymium doped yttrium aluminum garnet crystals from a melt containing constituent oxides, lead oxide, lead fluoride, and boron trioxide. By subjecting the melt to a controlled temperature cycle while maintaining a temperature gradient in the melt, large size, high quality crystals are obtained. Crystals produced by the disclosed method are suited for laser application.
Inventors
- 👤 Le Grand Gerard Van Uitert
- 👤 George John Zydzik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 23:57
CPC Classifications
C; C30; C30B; C30B9/00; C30B29/00; C30B29/10; C30B29/16; C30B29/22; C30B29/28
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
222 words
A method of growing neodymium-doped yttrium aluminum garnets from a melt of a mixture of flux components PbO, PbF 2 , B 2 O 3 , and constituent components Nd 2 O 3 , Y 2 O 3 , and Al 2 O 3 and maintained in an atmosphere containing a substantial amount of oxygen and at an initial temperature on the order of 1300° C CHARACTERIZED IN THAT said melt is (a) cooled at a first rate in the range of from 0.1° C per hour to 10° C per hour to a first temperature in the range of from 1050° C to 1200° C, (b) rapidly reheated to a temperature on the order of 1300° C, (c) cooled at a second rate in the range of from 0.1° C per hour to 3° C per hour to a second temperature in the range of from 1050° C to 1200° C, (d) maintained at said second temperature for a period of from 1-20 days, and (e) cooled at a third rate in the range of from 0.1° C per hour to 3° C per hour to a temperature in the range of from 900° C to 950° C and further CHARACTERIZED IN THAT a temperature gradient in the range of from 5° C/cm to 80° C/cm is maintained in said melt.
Claim 2
Independent Claim
222 words
A method of growing neodymium-doped yttrium aluminum garnets from a melt of a mixture of flux components PbO, PbF 2 , B 2 O 3 , and constituent components Nd 2 O 3 , Y 2 O 3 , and Al 2 O 3 and maintained in an atmosphere containing a substantial amount of oxygen and at an initial temperature on the order of 1300° C CHARACTERIZED IN THAT said melt is (a) cooled at a first rate in the range of from 0.1° C per hour to 10° C per hour to a first temperature in the range of from 1050° C to 1200° C, (b) rapidly reheated to a temperature on the order of 1300° C, (c) cooled at a second rate in the range of from 0.1° C per hour to 3° C per hour to a second temperature in the range of from 1050° C to 1200° C, (d) maintained at said second temperature for a period of from 1-20 days, and (e) cooled at a third rate in the range of from 0.1° C per hour to 3° C per hour to a temperature in the range of from 900° C to 950° C and further CHARACTERIZED IN THAT a temperature gradient in the range of from 5° C/cm to 80° C/cm is maintained in said melt.
Claim 3
Dependent Claim
32 words
Method of claim 1 in which the combined amount of crystal components in said melt is chosen in the range of from 15 weight percent to 40 weight percent of said mixture.
Claim 4
Dependent Claim
26 words
Method of claim 1 in which alumina is chosen in said mixture in an amount in excess of the stoichiometric amount by 50 to 150 percent.
Claim 5
Dependent Claim
41 words
Method of claim 1 in which said flux components are chosen in the ranges of from 30 weight percent to 70 weight percent PbO, 0.5 weight percent to 10 weight percent B 2 O 3 , and remainder PbF 2 .
Claim 6
Dependent Claim
33 words
Method of claim 1 in which Nd 2 O 3 is chosen in an amount of from 0.1 weight percent to 20 weight percent of the amount of Y 2 O 3 .
Claim 7
Dependent Claim
36 words
Method of claim 1 in which said melt also contains Cr 2 O 3 in an amount in the range of from 0.02 weight percent to one weight percent of the total amount of crystal components.
Claim 8
Dependent Claim
13 words
Method of claim 1 in which said first temperature is approximately 1130° C.
Claim 9
Dependent Claim
13 words
Method of claim 1 in which said second temperature is approximately 1130° C.
Claim 10
Dependent Claim
36 words
Method of claim 1 in which said temperature gradient is increased from an initial value in the range of from 5° C/cm to 40° C/cm to a value on the order of twice the initial value.
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) | 1980-03-21 | 1980-09-20 | 1981-03-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-03-21 | 1984-09-20 | 1985-03-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-03-21 | 1988-09-20 | 1989-03-22 | $7700.00 | Window Closed / Lapsed |