US4243697A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Self biased ferrite resonators
Assignee: United States Department of the Air Force
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Filing: 1979-03-14
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Granted: 1981-01-06
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Expires: 1999-03-14
Abstract
Abstract A method for preparing M-type hexagonal ferrite single crystals for use as self-biased ferrite resonators. M-type (BaO.6Fe 2 O 3 ) ferrite crystals are grown on a [111] Mg (In, Ga) 2 O 4 substrate using liquid phase epitaxial techniques. The substrate is immersed into a solute of (BaO, Fe 2 O 3 and ZnO) dissolved in a molten flux of molten (BaO and B 2 O 3 ) maintained in a supersaturated condition.
Inventors
- 👤 Howard L. Glass
- 👤 Jiin-Herny W. Liaw
- 👤 Tsutumo Kobayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:03
CPC Classifications
H; H01; H01P; H01P7/00; C; C04; C04B; C04B35/00; C04B35/01; C04B35/26; C04B35/2683; C30; C30B; C30B19/00; C30B19/02; C30B29/00; C30B29/10; C30B29/16; C30B29/22; H01F; H01F10/00; H01F10/08; H01F10/10; H01F10/18; H01F10/20; H01F10/205; H01F41/00; H01F41/14; H01F41/24; H01F41/28; Y; Y10; Y10S; Y10S428/00; Y10S428/90
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
241 words
A method for preparing an M-type, self-biased, hexagonal ferrite resonator composed of single crystals of barium hexaferrite on a spinel substrate which comprises the steps of: A. forming a homogenized, supersaturated melt composition by dissolving a solute composed of a mixture of Ba O, Fe 2 O 3 and ZnO into a molten flux composed of Ba CO 3 and B 2 O 3 in which the mole ratio of B a CO 3 : B 2 O 3 is 1.75, the mole ratio of Fe 2 O 3 : (B a CO 3 +B 2 O 3 ) is 0.164, and the mole ratio of Zn O: Fe 2 O 3 is 0.100; B. maintaining said melt composition at a temperature of from about 911° C. to 921° C. while simultaneously immersing a Mg (In, Ga) 2 O 4 spinel substrate into said melt composition for a period of time sufficient to effect the deposition on the surface of said substrate of barium hexaferrite single crystals that are substantially free of defects which can act as nucleation sites for magnetic domains; C. subjecting said single crystals to a magnetic field that is directed along the easy axis of anisotropy of said crystals and of sufficient magnitude to produce magnetic saturation in said crystals; and D. reducing said magnetic field to zero to produce single crystals capable of being maintained in a metastable state of magnetic saturation with zero applied field.
Claim 2
Independent Claim
241 words
A method for preparing an M-type, self-biased, hexagonal ferrite resonator composed of single crystals of barium hexaferrite on a spinel substrate which comprises the steps of: A. forming a homogenized, supersaturated melt composition by dissolving a solute composed of a mixture of Ba O, Fe 2 O 3 and ZnO into a molten flux composed of Ba CO 3 and B 2 O 3 in which the mole ratio of B a CO 3 : B 2 O 3 is 1.75, the mole ratio of Fe 2 O 3 : (B a CO 3 +B 2 O 3 ) is 0.164, and the mole ratio of Zn O: Fe 2 O 3 is 0.100; B. maintaining said melt composition at a temperature of from about 911° C. to 921° C. while simultaneously immersing a Mg (In, Ga) 2 O 4 spinel substrate into said melt composition for a period of time sufficient to effect the deposition on the surface of said substrate of barium hexaferrite single crystals that are substantially free of defects which can act as nucleation sites for magnetic domains; C. subjecting said single crystals to a magnetic field that is directed along the easy axis of anisotropy of said crystals and of sufficient magnitude to produce magnetic saturation in said crystals; and D. reducing said magnetic field to zero to produce single crystals capable of being maintained in a metastable state of magnetic saturation with zero applied field.
References Cited (Backward Citations)
US2946753A
Cited
US3093453A
Cited
US3113927A
Cited
US3114715A
Cited
US3498836A
Cited
US3770639A
Cited
US4177321A
Cited
US3906404A
Cited
US3959006A
Cited
US4027074A
Cited
US4050038A
Cited
US4122418A
Cited
US4093781A
Cited
US4183999A
Cited
US4182793A
Cited
US4189521A
Cited
US4174421A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-01-06 | 1984-07-07 | 1985-01-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-01-06 | 1988-07-07 | 1989-01-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-01-06 | 1992-07-07 | 1993-01-06 | $7700.00 | Window Closed / Lapsed |