Coupled resonator filter comprising a bridge
View Patent ↗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.
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 , wherein the first BAW resonator comprises a first bulk acoustic wave resonator (FBAR) and the second BAW resonator comprises a second FBAR.
36. A BAW resonator structure as claimed in claim 35 , 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.
37. A BAW resonator structure as claimed in claim 26 , wherein the first BAW resonator comprises a first solidly mounted resonator (SMR) and the second BAW resonator comprises a second SMR.
38. A BAW resonator structure as claimed in claim 37 , 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.
39. A coupled resonator filter (CRF) comprising the BAW resonator structure of claim 26 .
40. 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;
an acoustic reflector or a cavity disposed beneath the first BAW resonator
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 in the first piezoelectric layer, wherein the bridge is disposed about a perimeter of the BAW resonator structure, the bridge extending past an edge of the acoustic reflector or the cavity.
41. A BAW resonator structure as claimed in claim 40 , wherein the bridge has a trapezoidal cross-sectional shape.
42. A BAW resonator structure as claimed in claim 40 , further comprising a fill material having acoustic impedance disposed beneath the bridge.
43. A BAW resonator structure as claimed in claim 42 , wherein the fill material comprises non-etchable borosilicate glass (NEBSG).
44. A BAW resonator structure as claimed in claim 40 , wherein the first BAW resonator comprises a first bulk acoustic wave resonator (FBAR) and the second BAW resonator comprises a second FBAR.
45. A BAW resonator structure as claimed in claim 40 , wherein the first BAW resonator comprises a first solidly mounted resonator (SMR) and the second BAW resonator comprises a second SMR.
46. A coupled resonator filter (CRF) comprising the BAW resonator structure of claim 40 .