Magnetic materials with high curie temperatures and dielectric constants

Patent metadata

Field	Value
Publication number	US-11830647-B2
Application number	US-202217865188-A
Country	US
Kind code	B2
Filing date	Jul 14, 2022
Priority date	Jul 18, 2018
Publication date	Nov 28, 2023
Grant date	Nov 28, 2023

Abstract

Disclosed herein are ceramic materials, such as bismuth substituted garnets, which can have high curie temperatures and high dielectric constants. In certain implementations, indium can be incorporated into the ceramic to improve certain properties and to avoid calcium compensation. The ceramic materials disclosed herein can be particular advantageous for below resonance applications.

First claim

What is claimed is:

1. A ceramic material with low temperature sensitivity, the ceramic material comprising a composition of (Y or Gd) 3-x-2y Bi x Ca 2y Fe 5-z-y In z V y O 12 and having a dielectric constant of at least 25, 0<x<1.75, 0<y<0.8, and 0<z<0.7.

2. The ceramic material of claim 1 wherein the ceramic material does not include aluminum.

3. The ceramic material of claim 1 wherein 1.4<x<1.6, 0<y<0.8, and 0.2<z<0.7.

4. The ceramic material of claim 1 wherein the ceramic material has a Curie temperature of at least 210.

5. The ceramic material of claim 1 wherein the ceramic material has a Curie temperature of at least 220.

6. The ceramic material of claim 1 wherein the ceramic material has a magnetization of at least 1000.

7. The ceramic material of claim 1 wherein the ceramic material has a magnetization of at least 1200.

8. An isolator including the ceramic material of claim 1 .

9. A ceramic material with low temperature sensitivity, the ceramic material comprising a composition of (Y or Gd) 3-x-2y Bi x Ca 2y+a Fe 5-z-y-a In z V y Zr a O 12 and having a dielectric constant of at least 30, 0<x<1.75, 0<y<0.8, and 0<z+a<0.7.

10. The ceramic material of claim 9 wherein 1.4<x<1.6, 0<y<0.8, and 0.2<z+a<0.7.

11. The ceramic material of claim 9 wherein the ceramic material has a Curie temperature of at least 210.

12. The ceramic material of claim 9 wherein the ceramic material has a Curie temperature of at least 220.

13. The ceramic material of claim 9 wherein the ceramic material has a magnetization of at least 1000.

14. The ceramic material of claim 9 wherein the ceramic material has a magnetization of at least 1200.

15. An isolator including the ceramic material of claim 9 .

16. A method of forming a synthetic garnet having temperature insensitivity, the method comprising:
incorporating bismuth, calcium, indium, and vanadium into a crystal structure of a garnet structure to achieve a composition (Y or Gd) 3-x-2y Bi x Ca 2y Fe 5-z-y In z V y O 12 having a dielectric constant of at least 25, 0<x<1.75, 0<y<0.8, and 0<z<0.7.

17. The method of claim 16 wherein 1.4<x<1.6, 0<y<0.8, and 0.2<z<0.7.

18. The method of claim 16 wherein the synthetic garnet has a Curie temperature of at least 210.

19. A method of forming a synthetic garnet having temperature insensitivity, the method comprising:
incorporating bismuth, calcium, indium, vanadium, and zirconium into a crystal structure of a garnet structure to achieve a composition (Y or Gd) 3-x-2y Bi x Ca 2y+a Fe 5-z-y-a In z V y Zr a O 12 and having a dielectric constant of at least 30, 0<x<1.75, 0<y<0.8, and 0<z+a<0.7.

20. The method of claim 19 wherein 1.4<x<1.6, 0<y<0.8, and 0.2<z+a<0.7.

21. The method of claim 19 wherein the synthetic garnet has a Curie temperature of at least 210.

Assignees

• Skyworks Solutions Inc

Inventors

• Hill Michael David
• Cruickshank David Bowie

Classifications

• H01F1/344 Primary

  Ferrites, e.g. having a cubic spinel structure (X2+O)(Y23+O3), e.g. magnetite Fe3O4 · CPC title

• C01G49/0054

  containing one rare earth metal, yttrium or scandium · CPC title

• C01P2002/30

  Three-dimensional structures · CPC title

• C01P2002/50

  Solid solutions · CPC title

• C01P2002/77

  by unit-cell parameters, atom positions or structure diagrams · CPC title