Ultra-high dielectric constant garnet

Patent metadata

Field	Value
Publication number	US-11021400-B2
Application number	US-201916459059-A
Country	US
Kind code	B2
Filing date	Jul 1, 2019
Priority date	Jun 15, 2015
Publication date	Jun 1, 2021
Grant date	Jun 1, 2021

Abstract

Disclosed are embodiments of synthetic garnet materials for use in radiofrequency applications. In some embodiments, increased amounts of bismuth can be added into specific sites in the crystal structure of the synthetic garnet in order to boost certain properties, such as the dielectric constant and magnetization. Accordingly, embodiments of the disclosed materials can be used in high frequency applications, such as in base station antennas.

First claim

What is claimed is:

1. A ceramic material configured for radiofrequency applications, the ceramic material comprising:
a yttrium iron garnet crystal structure;
bismuth substituted into the crystal structure for at least some of the yttrium;
praseodymium, neodymium, samarium, dysprosium, ytterbium, or holmium substituted into the crystal structure for at least some of the yttrium; and
Ca or Zr substituted into the crystal structure for at least some of the yttrium.

2. The ceramic material of claim 1 wherein both calcium and zirconium are substituted into the crystal structure for at least some of the yttrium.

3. The ceramic material of claim 1 wherein praseodymium is substituted into the crystal structure.

4. The ceramic material of claim 1 wherein neodymium is substituted into the crystal structure.

5. The ceramic material of claim 1 wherein samarium is substituted into the crystal structure.

6. The ceramic material of claim 1 wherein dysprosium is substituted into the crystal structure.

7. The ceramic material of claim 1 wherein ytterbium is substituted into the crystal structure.

8. The ceramic material of claim 1 wherein holmium is substituted into the crystal structure.

9. The ceramic material of claim 1 wherein the ceramic material has a dielectric constant of at least 31.

10. The ceramic material of claim 1 wherein the ceramic material has a dielectric constant of at least 36.

11. The ceramic material of claim 1 wherein the ceramic material does not include sillenite.

12. A method of manufacturing a ceramic material, the method comprising:
providing a yttrium iron garnet crystal structure;
substituting bismuth into the crystal structure for at least some of the yttrium;
substituting praseodymium, neodymium, samarium, dysprosium, ytterbium, or holmium into the crystal structure for at least some of the yttrium; and
substituting Ca or Zr into the crystal structure for at least some of the yttrium.

13. The method of claim 12 wherein the ceramic material has a dielectric constant of at least 31.

14. The method of claim 12 wherein both calcium and zirconium are substituted into the crystal structure for at least some of the yttrium.

15. A radiofrequency device comprising:
a component formed from a ceramic having a yttrium iron garnet crystal structure;
bismuth substituting into the crystal structure for at least some of the yttrium;
praseodymium, neodymium, samarium, dysprosium, ytterbium, or holmium substituting into the crystal structure for at least some of the yttrium; and
Ca or Zr substituting into the crystal structure for at least some of the yttrium.

16. The radiofrequency device of claim 15 wherein the component is an antenna.

17. The radiofrequency device of claim 15 wherein the component is a circuit board.

18. The radiofrequency device of claim 15 wherein the ceramic has a dielectric constant of at least 31.

19. The radiofrequency device of claim 15 wherein both calcium and zirconium are substituted into the crystal structure for at least some of the yttrium.

20. The method of manufacturing of claim 12 wherein the ceramic material has a dielectric constant of at least 36.

21. The radio frequency device of claim 15 wherein the ceramic does not include sillenite.

22. The radio frequency device of claim 15 wherein the ceramic has a dielectric constant of at least 36.

Assignees

• Skyworks Solutions Inc

Inventors

• Cruickshank David Bowie
• Hill Michael David

Classifications

• C04B35/2641 Primary

  Compositions containing one or more ferrites of the group comprising rare earth metals and one or more ferrites of the group comprising alkali metals, alkaline earth metals or lead · CPC title

• C04B35/62655

  Drying, e.g. freeze-drying, spray-drying, microwave or supercritical drying · CPC title

• C04B2235/5427

  millimeter or submillimeter sized, i.e. larger than 0,1 mm · CPC title

• C04B2235/5454

  nanometer sized, i.e. below 100 nm · CPC title

• C04B2235/3298

  Bismuth oxides, bismuthates or oxide forming salts thereof, e.g. zinc bismuthate · CPC title