Composite hexagonal ferrite materials

Patent metadata

Field	Value
Publication number	US-10604450-B2
Application number	US-201715683500-A
Country	US
Kind code	B2
Filing date	Aug 22, 2017
Priority date	Aug 26, 2016
Publication date	Mar 31, 2020
Grant date	Mar 31, 2020

Abstract

Disclosed herein are embodiments of composite hexagonal ferrite materials formed from a combination of Y phase and Z phase hexagonal ferrite materials. Advantageously, embodiments of the material can have a high resonant frequency as well as a high permeability. In some embodiments, the materials can be useful for magnetodielectric antennas.

First claim

What is claimed is:

1. A composite hexagonal ferrite material, the material comprising:
a base y-phase hexagonal ferrite composition having a formula Sr 2-x Na x Co 2-x Sc x Fe 12 O 22 , 0<x<1; and
a doped-in z-phase hexagonal ferrite composition to form the composite hexagonal ferrite material, the composite hexagonal ferrite m-phase hexagonal ferrite composition material having a Q value of greater than about 15 at 1 GHz.

2. The composite hexagonal ferrite material of claim 1 wherein the material has a Q value of greater than about 20 at 1 GHz.

3. The composite hexagonal ferrite material of claim 1 wherein the material has a real permeability of between 3 and 7 at 1 GHz.

4. The composite hexagonal ferrite material of claim 1 wherein the material has a real permeability of greater than 6.

5. The composite hexagonal ferrite material of claim 1 wherein the z-phase hexagonal ferrite composition comprises Ba 1.4 Sr 0.8 Na 0.8 Co 1.2 Sc 0.8 Fe 24 O 41 .

6. The composite hexagonal ferrite material of claim 1 wherein the y-phase hexagonal ferrite composition comprises Sr 1.6 Na 0.4 Sc 0.4 Co 1.6 Fe 12 O 22 .

7. The composite hexagonal ferrite material of claim 1 further including Ba 3 Co 2 Fe 24 O 41 , Sr 3 Co 2 Fe 24 O 41 , MnO 2 , Al 2 O 3 , or SiO 2 .

8. A method of forming a composite hexagonal ferrite material the method comprising combing a y-phase hexagonal ferrite composition having a formula Sr 2-x Na x Co 2-x Sc x Fe 12 O 22 , 0<x<1, at least partially with a z-phase hexagonal ferrite composition, thereby forming a composite hexagonal ferrite material having a Q value of greater than about 15 at 1 GHz.

9. The method of claim 8 , further including doping the material with indium or zirconium to reduce strontium levels.

10. The method of claim 8 wherein the composite hexagonal ferrite material has a Q value of greater than about 20 at 1 GHz.

11. The method of claim 8 wherein the composite hexagonal ferrite material has a real permeability of between 3 and 7 at 1 GHz.

12. The method of claim 8 wherein the z-phase hexagonal ferrite composition comprises Ba 1.4 Sr 0.8 Na 0.8 Co 1.2 Sc 0.8 Fe 24 O 41 .

13. The method of claim 8 wherein the y-phase hexagonal ferrite composition comprises Sr 1.6 Na 0.4 Sc 0.4 Co 1.6 Fe 12 O 22 .

14. An antenna formed from a composite hexagonal ferrite material, the antenna comprising:
a base y-phase hexagonal ferrite composition having a formula Sr 2-x Na x Co 2-x Sc x Fe 12 O 22 , 0<x<1; and
a doped-in z-phase hexagonal ferrite composition to form the composite hexagonal ferrite material, the composite hexagonal ferrite material having a Q value of greater than about 15 at 1 GHz.

15. The antenna of claim 14 wherein the antenna is part of a wireless device.

16. The antenna of claim 15 wherein the antenna is part of a tablet.

17. The antenna of claim 14 wherein the antenna is usable at frequencies of 1 GHz and above.

18. The antenna of claim 14 wherein the composite hexagonal ferrite material has a Q value of greater than about 20 at 1 GHz and a real permeability of between 3 and 7 at 1 GHz.

19. The antenna of claim 14 wherein the z-phase hexagonal ferrite composition comprises Ba 1.4 Sr 0.8 Na 0.8 Co 1.2 Sc 0.8 Fe 24 O 41 .

20. The antenna of claim 14 wherein the y-phase hexagonal ferrite composition comprises Sr 1.6 Na 0.4 Sc 0.4 Co 1.6 Fe 12 O 22 .

Assignees

• Skyworks Solutions Inc

Inventors

• Hill Michael David
• Polisetty Srinivas
• Griffith Constance M

Classifications

• C01P2006/42

  Magnetic properties · CPC title

• C04B35/2633

  containing barium, strontium or calcium · CPC title

• C01B33/20

  Silicates (persilicates C01B15/14 {; containing aluminium C01B33/26}) · CPC title

• C04B2235/767

  Hexagonal symmetry, e.g. beta-Si3N4, beta-Sialon, alpha-SiC or hexa-ferrites · CPC title

• C01P2004/82

  two phases having the same anion, e.g. both oxidic phases · CPC title