Modified scheelite material for co-firing

Patent metadata

Field	Value
Publication number	US-11565976-B2
Application number	US-201916440221-A
Country	US
Kind code	B2
Filing date	Jun 13, 2019
Priority date	Jun 18, 2018
Publication date	Jan 31, 2023
Grant date	Jan 31, 2023

Abstract

Disclosed herein are embodiments of low temperature co-fireable scheelite materials which can be used in combination with high dielectric materials, such as nickel zinc ferrite, to form composite structures, in particular for isolators and circulators for radiofrequency components. In some embodiments, the scheelite material can include aluminum oxide for temperature expansion regulation.

First claim

What is claimed is:

1. A composite material for use as a radiofrequency component comprising:
a rod including a magnetic garnet material; and
a ring surrounding the rod, the ring being formed from a scheelite material having a firing temperature of 950° C. or below.

2. The composite material of claim 1 wherein the scheelite material has the chemical formula Li 0.05 Bi 0.95 Mo 0.1 V 0.9 O 4 .

3. The composite material of claim 1 wherein the scheelite material has the chemical formula Bi 1-2x-z R z M′ x V 1-x M″ x O 4 , R being a rare earth element La, Ce, Pr, Sm, Nd, Gd, Dy, Tb, Ho, Er, Tm, Yb, Lu, Y or Sc, M′ being Li, Na, or K, and M″ being Mo or W.

4. The composite material of claim 1 wherein the scheelite material has the chemical formula (Na,Li) 0.5x Bi 1-0.5x (Mo,W) x V 1-x O 4 , x being between 0 and 0.5.

5. The composite material of claim 1 wherein the scheelite material includes between 1 and 10 wt. % aluminum oxide.

6. The composite material of claim 5 wherein the scheelite material includes between 2 and 6 wt. % aluminum oxide.

7. The composite material of claim 1 wherein the scheelite material includes BiVO 4 .

8. The composite material of claim 1 wherein the scheelite material includes (Na 0.35 Bi 0.65 )(Mo 0.7 V 0.3 )O 4 .

9. The composite material of claim 1 wherein the scheelite material includes (Na 0.2 Bi 0.8 )(Mo 0.4 V 0.6 )O 4 .

10. A method of forming a composite material for use as an isolator or circulator in a radiofrequency device, the method comprising:
providing a rod including a magnetic garnet material;
providing an outer ring having a scheelite crystalline structure, the outer ring having a firing temperature of 950° C. or below;
entering the rod within an aperture in the outer ring; and
co-firing the outer ring and the rod together at a temperature of 950° C. or below to shrink the outer ring around an outer surface of the magnetic garnet material rod without the use of adhesive or glue and form a composite material.

11. The method of claim 10 wherein the outer ring has the chemical formula Li 0.05 Bi 0.95 Mo 0.1 V 0.9 O 4 .

12. The method of claim 10 wherein the scheelite material has the chemical formula Bi 1-2x-z R z M′ x V 1-x M″ x O 4 , R being a rare earth element La, Ce, Pr, Sm, Nd, Gd, Dy, Tb, Ho, Er, Tm, Yb, Lu, Y or Sc, M′ being Li, Na, or K, and M″ being Mo or W.

13. The method of claim 10 wherein the scheelite material has the chemical formula (Na,Li) 0.5x Bi 1-0.5x (Mo,W) x V 1-x O 4 , x being between 0 and 0.5.

14. The method of claim 10 wherein the scheelite material includes between 1 and 10 wt. % aluminum oxide.

15. The method of claim 14 wherein the scheelite material includes between 2 and 6 wt. % aluminum oxide.

16. The method of claim 10 wherein the magnetic garnet material rod includes Bi, Ca, Zr, Y, Fe, and O.

17. The method of claim 10 wherein the scheelite material includes BiVO 4 .

18. The method of claim 10 further including slicing the composite material.

19. A radiofrequency isolator or circulator comprising:
a rod including a magnetic garnet material; and
a ring surrounding the rod, the ring being formed from a scheelite material having a firing temperature of 950° C. or below.

20. The radiofrequency of claim 19 wherein the ring reduces in diameter around the magnetic garnet material rod during firing so that no adhesive is used to connect the ring with the magnetic garnet material rod.

Assignees

• Skyworks Solutions Inc

Inventors

• Hill Michael David
• Cruickshank David Bowie
• Shunkwiler Jeffrey Alan
• Jiang John Jianzhong
• Firor David Martin
• Coats Neil Bruce

Classifications

• C04B2235/3227

  Lanthanum oxide or oxide-forming salts thereof · CPC title

• C04B2235/3256

  Molybdenum oxides, molybdates or oxide forming salts thereof, e.g. cadmium molybdate · CPC title

• C04B37/001

  directly with other burned ceramic articles · CPC title

• H01P1/36

  Isolators · CPC title

• C04B2237/84

  Joining of a first substrate with a second substrate at least partially inside the first substrate, where the bonding area is at the inside of the first substrate, e.g. one tube inside another tube · CPC title