Ultra-high dielectric constant garnet

Patent metadata

Field	Value
Publication number	US-10370299-B2
Application number	US-201715715443-A
Country	US
Kind code	B2
Filing date	Sep 26, 2017
Priority date	Jun 15, 2015
Publication date	Aug 6, 2019
Grant date	Aug 6, 2019

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. An ultra-high dielectric constant garnet comprising:
an yttrium iron garnet crystal structure with at least some yttrium being substituted out for bismuth, at least some yttrium being substituted by gadolinium, and charge balance achieved by calcium or zirconium substituting for at least some yttrium.

2. The ultra-high dielectric constant garnet of claim 1 wherein the ultra-high dielectric constant garnet has a dielectric constant of at least 40.

3. The ultra-high dielectric constant garnet of claim 1 wherein the ultra-high dielectric constant garnet does not contain sillenite.

4. The ultra-high dielectric constant garnet of claim 1 further including hafnium or titanium incorporated into octahedral sites of the yttrium iron garnet crystal structure.

5. The ultra-high dielectric constant garnet of claim 1 wherein the ultra-high dielectric constant garnet contains no yttrium.

6. The ultra-high dielectric constant garnet of claim 1 wherein the ultra-high dielectric constant garnet has a magnetization of 1600 4πM s or above.

7. A method of producing an ultra-high dielectric constant garnet, the method comprising:
providing an yttrium iron garnet structure;
substituting out at least some yttrium for bismuth;
substituting out at least some yttrium for gadolinium; and
charge balancing by substituting out at least some yttrium for calcium or zirconium.

8. The method of claim 7 wherein the ultra-high dielectric constant garnet has a dielectric constant of at least 40.

9. The method of claim 7 wherein the ultra-high dielectric constant garnet does not contain sillenite.

10. The method of claim 7 wherein the ultra-high dielectric constant garnet contains no yttrium.

11. The method of claim 7 further including incorporating hafnium or titanium into octahedral sites of the yttrium iron garnet crystal structure.

12. The method of claim 7 wherein the ultra-high dielectric constant garnet has a magnetization of 1600 4πM s or above.

13. A radiofrequency device comprising:
a component formed from an ultra-high dielectric constant garnet having an yttrium iron garnet crystal structure with at least some yttrium being substituted out for bismuth, at least some yttrium being substituted by gadolinium, and charge balance achieved by calcium or zirconium substituting for at least some yttrium.

14. The radiofrequency device of claim 13 wherein the component is an antenna.

15. The radiofrequency device of claim 13 wherein the radiofrequency device is a radiofrequency circuit board.

16. The radiofrequency device of claim 13 wherein the ultra-high dielectric constant garnet does not contain sillenite.

17. The radiofrequency device of claim 13 wherein the ultra-high dielectric constant garnet contains no yttrium.

18. The radiofrequency device of claim 13 wherein the ultra-high dielectric constant garnet has a dielectric constant of at least 40.

19. The radiofrequency device of claim 13 wherein the ultra-high dielectric constant garnet has a magnetization of 1600 4πM s or above.

20. The radiofrequency device of claim 13 further including hafnium or titanium incorporated into octahedral sites of the yttrium iron garnet crystal structure.

Assignees

• Skyworks Solutions Inc

Inventors

• Cruickshank David Bowie
• Hill Michael David

Classifications

• C04B2235/5427

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

• 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

• C04B2235/3208

  Calcium oxide or oxide-forming salts thereof, e.g. lime · CPC title

• C04B2235/3239

  Vanadium oxides, vanadates or oxide forming salts thereof, e.g. magnesium vanadate · CPC title

• C04B2235/77

  Density · CPC title