Coupled resonator filter comprising a bridge

Patent metadata

Field	Value
Publication number	US-9154112-B2
Application number	US-201113036489-A
Country	US
Kind code	B2
Filing date	Feb 28, 2011
Priority date	Feb 28, 2011
Publication date	Oct 6, 2015
Grant date	Oct 6, 2015

Abstract

In accordance with a representative embodiment, a bulk acoustic wave (BAW) resonator structure, comprises: a first BAW resonator comprising a first lower electrode, a first upper electrode and a first piezoelectric layer disposed between the first lower electrode and the first upper electrode; a second BAW resonator comprising a second lower electrode, a second upper electrode and a second piezoelectric layer disposed between the second lower electrode and the second upper electrode; an acoustic coupling layer disposed between the first BAW resonator and the second BAW resonator; and a bridge disposed between the first lower electrode of the first BAW resonator and the second upper electrode of the second BAW resonator.

First claim

The invention claimed is:

1. A bulk acoustic wave (BAW) resonator structure, comprising:
a first BAW resonator comprising a first lower electrode, a first upper electrode and a first piezoelectric layer disposed between the first lower electrode and the first upper electrode;
a second BAW resonator comprising a second lower electrode, a second upper electrode and a second piezoelectric layer disposed between the second lower electrode and the second upper electrode;
an acoustic coupling layer disposed between the first BAW resonator and the second BAW resonator; and
a first bridge disposed between the first lower electrode of the first BAW resonator and the second upper electrode of the second BAW resonator, wherein the BAW resonator structure has a first perimeter, and the first bridge is disposed completely along the first perimeter; and
a second bridge disposed between the first upper electrode of the first BAW resonator and the second lower electrode of the second BAW resonator.

2. A BAW resonator structure as claimed in claim 1 , wherein the first bridge has a trapezoidal cross-sectional shape.

3. A BAW resonator structure as claimed in claim 1 , further comprising a fill material having acoustic impedance disposed beneath the first bridge.

4. A BAW resonator structure as claimed in claim 3 , wherein the fill material comprises non-etchable borosilicate glass (NEBSG).

5. A BAW resonator structure as claimed in claim 1 , further comprising a fill material having acoustic impedance disposed beneath the second bridge.

6. A BAW resonator structure as claimed in claim 5 , wherein the fill material comprises non-etchable borosilicate glass (NEBSG).

7. A BAW resonator structure as claimed in claim 1 , wherein the second bridge has a trapezoidal cross-sectional shape.

8. A BAW resonator structure as claimed in claim 1 , wherein neither the first bridge nor the second bridge is disposed in the first lower electrode of the BAW resonator structure.

9. A BAW resonator structure as claimed in claim 1 , wherein the first BAW resonator comprises a first bulk acoustic wave resonator (FBAR) and the second BAW resonator comprises a second FBAR.

10. A BAW resonator structure as claimed in claim 1 , wherein the first BAW resonator comprises a first solidly mounted resonator (SMR) and the second BAW resonator comprises a second SMR.

11. A coupled resonator filter (CRF) comprising the BAW resonator structure of claim 1 .

12. A bulk acoustic wave (BAW) resonator structure, comprising:
a first BAW resonator comprising a first lower electrode, a first upper electrode and a first piezoelectric layer disposed between the first lower electrode and the first upper electrode;
a second BAW resonator comprising a second lower electrode, a second upper electrode and a second piezoelectric layer disposed between the second lower electrode and the second upper electrode;
an acoustic coupling layer disposed between the first BAW resonator and the second BAW resonator;
a first bridge disposed in the first upper electrode of the first BAW resonator; and
a second bridge disposed in the second upper electrode, wherein the first bridge is disposed about a first perimeter of the BAW resonator structure.

13. A BAW resonator structure as claimed in claim 12 , wherein the second bridge is disposed about a second perimeter of the BAW resonator structure.

14. A BAW resonator structure as claimed in claim 12 , wherein the first bridge has a trapezoidal cross-sectional shape.

15. A BAW resonator structure as claimed in claim 12 , wherein the second bridge has a trapezoidal cross-sectional shape.

16. A BAW resonator structure as claimed in claim 12 , further comprising a fill material having acoustic impedance disposed beneath the first bridge.

17. A BAW resonator structure as claimed in claim 16 , wherein the fill material comprises non-etchable borosilicate glass (NEBSG).

18. A BAW resonator structure as claimed in claim 12 , further comprising a fill material having acoustic impedance disposed beneath the second bridge.

19. A BAW resonator structure as claimed in claim 18 , wherein the fill material comprises non-etchable borosilicate glass (NEBSG).

20. A BAW resonator structure as claimed in claim 12 , wherein neither the first bridge nor the second bridge is disposed in the first lower electrode of the BAW resonator structure.

21. A RAW resonator structure as claimed in claim 12 , wherein the first RAW resonator comprises a first bulk acoustic wave resonator (FBAR) and the second BAW resonator comprises a second FBAR.

22. A BAW resonator structure as claimed in claim 21 , further comprising a cavity disposed beneath the first and second FBARs, wherein the first bridge and the second bridge extend past an edge of the cavity.

23. A BAW resonator structure as claimed in claim 12 , wherein the first BAW resonator comprises a first solidly mounted resonator (SMR) and the second BAW resonator comprises a second SMR.

24. A BAW resonator structure as claimed in claim 23 , further comprising a Bragg reflector disposed beneath the first and second FBARs, wherein the first bridge and the second bridge extend past an edge of the Bragg reflector.

25. A coupled resonator filter (CRF) comprising the BAW resonator structure of claim 12 .

26. A bulk acoustic wave (BAW) resonator structure, comprising:
a first BAW resonator comprising a first lower electrode, a first upper electrode and a first piezoelectric layer disposed between the first lower electrode and the first upper electrode;
a second BAW resonator comprising a second lower electrode, a second upper electrode and a second piezoelectric layer disposed between the second lower electrode and the second upper electrode;
an acoustic coupling layer disposed between the first BAW resonator and the second BAW resonator;
a first bridge disposed in the first piezoelectric layer; and
a second bridge disposed in the second piezoelectric layer, wherein the first bridge is disposed about a first perimeter of the BAW resonator structure.

27. A BAW resonator structure as claimed in claim 26 , wherein the second bridge is disposed about a second perimeter of the BAW resonator structure.

28. A BAW resonator structure as claimed in claim 26 , wherein the first bridge has a trapezoidal cross-sectional shape.

29. A BAW resonator structure as claimed in claim 26 , wherein the second bridge has a trapezoidal cross-sectional shape.

30. A BAW resonator structure as claimed in claim 26 , further comprising a fill material having acoustic impedance disposed beneath the first bridge.

31. A BAW resonator structure as claimed in claim 30 , wherein the fill material comprises non-etchable borosilicate glass (NEBSG).

32. A BAW resonator structure as claimed in claim 26 , further comprising a fill material having acoustic impedance disposed beneath the second bridge.

33. A BAW resonator structure as claimed in claim 32 , wherein the fill material comprises non-etchable borosilicate glass (NEBSG).

34. A BAW resonator structure as claimed in claim 26 , wherein neither the first bridge nor the second bridge is disposed in the first lower electrode of the BAW resonator structure.

35. A BAW resonator structure as claimed in claim 26 , wh

Assignees

• Burak Dariusz
• Avago Technologies General Ip

Inventors

• Burak Dariusz

Classifications

• H03H9/132

  characterized by a particular shape · CPC title

• H03H9/02118

  of lateral leakage between adjacent resonators · CPC title

• H03H9/02086

  Means for compensation or elimination of undesirable effects · CPC title

• H03H9/584 Primary

  Coupled Resonator Filters [CFR] · CPC title

• H03H9/58 Primary

  Multiple crystal filters · CPC title