Stacked acoustic resonator comprising a bridge
View Patent ↗In accordance with a representative embodiment, a bulk acoustic wave (BAW) resonator structure, comprises: a first electrode disposed over a substrate; a first piezoelectric layer disposed over the first electrode; a second electrode disposed over the first piezoelectric layer; a second piezoelectric layer disposed over the second electrode; a third electrode disposed over the second piezoelectric layer; and a bridge disposed between the first electrode and the third electrode.
1. A bulk acoustic wave (BAW) resonator structure, comprising:
a substrate comprising a cavity;
a first electrode disposed over the substrate;
a planarization layer disposed over the substrate and adjacent to the first electrode, the planarization layer not overlapping the cavity;
a first piezoelectric layer disposed over the first electrode;
a second electrode disposed over the first piezoelectric layer;
a second piezoelectric layer disposed over the second electrode;
a third electrode disposed over the second piezoelectric layer; and
a bridge disposed between the first electrode and the third electrode, the bridge extending past an edge of the cavity or acoustic reflector.
2. A BAW resonator structure as claimed in claim 1 , wherein the bridge is a first bridge, and the BAW resonator structure further comprises a second bridge disposed between the first electrode and the third electrode.
3. A BAW resonator structure as claimed in claim 2 , wherein the BAW resonator structure has a first perimeter bounding an active region of the BAW resonator structure, and the first bridge is disposed along the first perimeter.
4. A BAW resonator structure as claimed in claim 3 , the BAW resonator structure having a second perimeter bounding the active region of the BAW resonator structure, and a second bridge is disposed along the second perimeter.
5. A BAW resonator structure as claimed in claim 2 , wherein the first bridge comprises a fill material having an acoustic impedance.
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 2 , wherein the second bridge comprises a fill material having an acoustic impedance.
8. A BAW resonator structure as claimed in claim 7 , wherein the fill material comprises non-etchable borosilicate glass (NEBSG).
9. A BAW resonator structure as claimed in claim 2 , wherein neither the first bridge nor the second bridge is disposed in the first electrode.
10. A BAW resonator structure as claimed in claim 1 , wherein the bridge comprises a fill material having an acoustic impedance.
11. A BAW resonator structure as claimed in claim 1 , wherein the bridge has a trapezoidal cross-sectional shape.
12. A BAW resonator structure as claimed in claim 1 , wherein the bridge comprises a first bridge disposed in the second electrode, and the BAW resonator structure further comprises a second bridge disposed in the third electrode.
13. A BAW resonator structure as claimed in claim 12 , wherein the first bridge is disposed along a first perimeter of the BAW resonator structure.
14. A BAW resonator structure as claimed in claim 13 , wherein the second bridge is disposed along a second perimeter of the BAW resonator structure.
15. A BAW resonator structure as claimed in claim 1 , wherein the bridge comprises a first bridge disposed in the first piezoelectric layer, and the BAW resonator structure further comprises a second bridge disposed in the second piezoelectric layer.
16. A BAW resonator structure as claimed in claim 15 , wherein the first bridge is disposed along a first perimeter of the BAW resonator structure.
17. A BAW resonator structure as claimed in claim 16 , wherein the second bridge is disposed along a second perimeter of the BAW resonator structure.
18. A BAW resonator structure as claimed in claim 1 , the planarization layer being a first planarization layer, and the BAW resonator structure further comprises a second planarization layer disposed over the first piezoelectric layer and adjacent to the second electrode, wherein the second planarization layer does not overlap the acoustic reflector.
19. A bulk acoustic wave (BAW) resonator structure, comprising:
a substrate comprising a cavity;
a first electrode disposed over the substrate;
a planarization layer disposed over the substrate and adjacent to the first electrode, the planarization layer not overlapping the cavity;
a first piezoelectric layer disposed over the first electrode;
a second electrode disposed over the first piezoelectric layer;
a second piezoelectric layer disposed over the second electrode;
a third electrode disposed over the second piezoelectric layer;
a bridge disposed between the first electrode and the third electrode, the bridge extending past an edge of the cavity or acoustic reflector; and
an inner raised region disposed over the third electrode.
20. A BAW resonator structure as claimed in claim 19 , further comprising an outer raised region disposed over the third electrode.
21. A BAW resonator structure as claimed in claim 19 , wherein the BAW resonator structure has a first perimeter bounding an active region of the BAW resonator structure, the bridge is disposed along the first perimeter, and the inner raised region is in the active region.
22. A BAW resonator structure as claimed in claim 19 , the planarization layer being a first planarization layer, and the BAW resonator structure further comprises a second planarization layer disposed over the first piezoelectric layer and adjacent to the second electrode, wherein the second planarization layer does not overlap the acoustic reflector.
23. A BAW resonator structure as claimed in claim 19 , wherein the bridge is a first bridge, and the BAW resonator structure further comprises a second bridge disposed between the first electrode and the third electrode.
24. A BAW resonator structure as claimed in claim 23 , wherein the first bridge comprises a fill material having an acoustic impedance.
25. A BAW resonator structure as claimed in claim 23 , wherein the second bridge comprises a fill material having an acoustic impedance.
26. A BAW resonator structure as claimed in claim 19 , wherein the BAW resonator structure has a first perimeter bounding an active region of the BAW resonator structure, and the bridge is disposed along the first perimeter.
27. A BAW resonator structure as claimed in claim 26 , wherein the BAW resonator structure has a second perimeter bounding the active region of the BAW resonator structure, and a second bridge is disposed along the second perimeter.
28. A BAW resonator structure as claimed in claim 19 , wherein the bridge comprises a fill material having an acoustic impedance.
29. A BAW resonator structure as claimed in claim 19 , wherein the bridge comprises a first bridge disposed in the second electrode, and the BAW resonator structure further comprises a second bridge disposed in the third electrode.
30. A BAW resonator structure as claimed in claim 29 , wherein the first bridge is disposed along a first perimeter of the BAW resonator structure.
31. A BAW resonator structure as claimed in claim 30 , wherein the second bridge is disposed along a second perimeter of the BAW resonator structure.
32. A BAW resonator as claimed in claim 19 , wherein the bridge comprises a first bridge disposed in the first piezoelectric layer, and the BAW resonator structure further comprises a second bridge disposed in the second piezoelectric layer.
33. A bulk acoustic wave (BAW) resonator structure, comprising:
a substrate comprising an acoustic reflector;
a first electrode disposed over the substrate;
a planarization layer disposed over the substrate and adjacent to the first electrode, the planarization layer not overlapping the acoustic reflector;
a first piezoelectric layer disposed over the first electrode;
a second electrode disposed over the first piezoelectric layer;
a second piezoelectric layer disposed over the second electrode;
a third electrode disposed over the second piezoelectric layer; and
a bridge disposed between the first electrode and the third electrode, the bridge extending past an edge of the acoustic reflector.
34. A BAW resonator structure as claimed in claim 33 , wherein the bridge is a first bridge, and the BAW resonator structure further comprises a second bridge disposed between the first electrode and the third electrode.
35. A BAW resonator structure as claimed in claim 34 , wherein the BAW resonator structure has a first perimeter bounding an active region of the BAW resonator structure, and the first bridge is disposed along the first perimeter.
36. A BAW resonator structure as claimed in claim 35 , the BAW resonator structure having a second perimeter bounding the active region of the BAW resonator structure, and the second bridge is disposed along the second perimeter.
37. A BAW resonator structure as claimed in claim 34 , wherein the first bridge comprises a fill material having an acoustic impedance.
38. A BAW resonator structure as claimed in claim 37 , wherein the first bridge is disposed along a first perimeter of the BAW resonator structure.
39. A BAW resonator structure as claimed in claim 37 , wherein the fill material comprises non-etchable borosilicate glass (NEBSG).
40. A BAW resonator structure as claimed in claim 34 , wherein the second bridge comprises a fill material having an acoustic impedance.
41. A BAW resonator structure as claimed in claim 34 , wherein neither the first bridge nor the second bridge is disposed in the first electrode.
42. A BAW resonator structure as claimed in claim 33 , wherein the bridge comprises a fill material having an acoustic impedance.
43. A BAW resonator structure as claimed in claim 42 , wherein a second bridge is disposed along a second perimeter of the BAW resonator structure.
44. A BAW resonator structure as claimed in claim 42 , wherein the fill material comprises non-etchable borosilicate glass (NEBSG).
45. A BAW resonator structure as claimed in claim 33 , wherein the bridge has a trapezoidal cross-sectional shape.
46. A BAW resonator structure as claimed in claim 45 , wherein a second bridge is disposed along a second perimeter of the BAW resonator structure.
47. A BAW resonator structure as claimed in claim 33 , wherein the bridge is a first bridge disposed in the second electrode, and the BAW resonator structure further comprises a second bridge disposed in the third electrode.
48. A BAW resonator structure as claimed in claim 33 , wherein the bridge is a first bridge disposed in the first piezoelectric layer, and the BAW resonator structure further comprises a second bridge disposed in the second piezoelectric layer.
49. A bulk acoustic wave (BAW) resonator structure, comprising:
a substrate comprising an acoustic reflector;
a first electrode disposed over the substrate;
a planarization layer disposed over the substrate and adjacent to the first electrode, the planarization layer not overlapping the acoustic reflector;
a first piezoelectric layer disposed over the first electrode;
a second electrode disposed over the first piezoelectric layer;
a second piezoelectric layer disposed over the second electrode;
a third electrode disposed over the second piezoelectric layer;
a bridge disposed between the first electrode and the third electrode, the bridge extending past an edge of the acoustic reflector; and
an inner raised region disposed over the third electrode.
50. A BAW resonator structure as claimed in claim 49 , further comprising an outer raised region disposed over the third electrode.
51. A BAW resonator structure as claimed in claim 49 , wherein the BAW resonator structure has a first perimeter bounding an active region of the BAW resonator structure, the bridge is disposed along the first perimeter, and the inner raised region is in the active region.
52. A BAW resonator structure as claimed in claim 49 , the planarization layer being a first planarization layer, and the BAW resonator structure further comprises a second planarization layer disposed over the first piezoelectric layer and adjacent to the second electrode, wherein the second planarization layer does not overlap the acoustic reflector.
53. A BAW resonator structure as claimed in claim 49 , wherein the bridge is a first bridge, and the BAW resonator structure further comprises a second bridge disposed between the first electrode and the third electrode.
54. A BAW resonator structure as claimed in claim 53 , wherein the first bridge comprises a fill material having an acoustic impedance.
55. A BAW resonator structure as claimed in claim 53 , wherein the second bridge comprises a fill material having an acoustic impedance.
56. A BAW resonator structure as claimed in claim 49 , wherein the BAW resonator structure has a first perimeter bounding an active region of the BAW resonator structure, and the bridge is disposed along the first perimeter.
57. A BAW resonator structure as claimed in claim 56 , wherein the BAW resonator structure has a second perimeter bounding the active region of the BAW resonator structure, and a second bridge is disposed along the second perimeter.
58. A BAW resonator structure as claimed in claim 49 , wherein the bridge comprises a fill material having an acoustic impedance.
59. A BAW resonator structure as claimed in claim 49 , wherein the bridge comprises a first bridge disposed in the second electrode, and the BAW resonator structure further comprises a second bridge disposed in the third electrode.
60. A BAW resonator structure as claimed in claim 59 , wherein the first bridge is disposed along a first perimeter of the BAW resonator structure.
61. A BAW resonator structure as claimed in claim 60 , wherein the second bridge is disposed along a second perimeter of the BAW resonator structure.
62. A BAW resonator structure as claimed in claim 49 , wherein the bridge comprises a first bridge disposed in the first piezoelectric layer, and the BAW resonator structure further comprises a second bridge disposed in the second piezoelectric layer.