Support and decoupling structure for an acoustic resonator, acoustic resonator and corresponding integrated circuit
An acoustic resonator assembly includes a layer of high-acoustic-impedance material and a layer of low-acoustic-impedance material made of a low-electrical-permittivity material. This assembly may support the resonator over an interconnect layer or act as a decoupling assembly between two active elements of the resonator. The assembly may alternatively include three low-acoustic impedance layers. Alternatively, the assembly may include three acoustic impedance layers wherein two of the layers are low acoustic impedance layers and the third layer has a higher acoustic impedance than the first two or alternatively is a high-acoustic impedance layer.
1. A structure, comprising:
a substrate;
an interconnect layer above the substrate;
an acoustic resonator structure including a bottom portion embodied in the interconnect layer, the acoustic resonator structure including a decoupling structure positioned between first and second acoustic resonators, comprising:
a layer of high-acoustic-impedance material; and
a layer of low-acoustic-impedance SiOC material having a low-electrical-permittivity, wherein the low-acoustic-impedance SiOC material is a porous SiOC material including pores filled with Argon.
2. The structure according to claim 1 , wherein the layer of low-acoustic-impedance SiOC material is placed between one of the two acoustic resonators and said layer of high-acoustic-impedance material.
3. The structure according to claim 1 , wherein the layer of high-acoustic-impedance material is made of a same material as an electrode of one of the acoustic resonators.
4. The structure according to claim 1 , wherein the layer of low-acoustic-impedance SiOC material comprises a plurality of sublayers comprising SiOC.
5. The structure according to claim 1 , wherein the high-acoustic-impedance material comprises at least one material selected in the group consisting of: aluminum, copper, nickel, gold, platinum, molybdenum.
6. An acoustic resonator, comprising:
a substrate;
an interconnect layer above the substrate and including an opening with side walls;
at least two active elements;
a support layer between a first of the active elements and the interconnect layer, the support layer positioned within the opening and embodied in the interconnect layer, the two active elements separated by a groove from the side walls of the opening; and
a decoupling assembly placed between the two active elements comprising at least a layer of low-acoustic-impedance material made of a low-electrical-permittivity material;
wherein the low-acoustic-impedance material comprises a porous SiOC material including pores filled with Argon.
7. The resonator according to claim 6 , wherein an active element comprises at least one piezoelectric layer placed between electrodes.
8. The resonator according to claim 6 , wherein the decoupling assembly is placed between an upper electrode of a first active element and a lower electrode of a second active element.
9. The resonator according to claim 6 , wherein an electrode comprises at least one material selected from the group consisting of: aluminum, copper, nickel, gold,
platinum, molybdenum.
10. The resonator according to claim 6 , wherein the decoupling assembly comprises no more than one layer of low-acoustic-impedance material.
11. The resonator according to claim 6 , wherein the decoupling assembly comprises two layers of low-acoustic-impedance material.
12. The resonator according to claim 6 , wherein the decoupling assembly comprises three layers of low-acoustic-impedance material.
13. An integrated circuit, comprising:
a substrate;
a set of interconnects in an interconnect layer, wherein the interconnect layer includes an opening formed in a top surface thereof having side walls; and
an acoustic resonator positioned at least partially within the opening in the top surface of the interconnect layer that is provided with at least two active elements and with a decoupling layer positioned between each pair of active elements, the active elements being separated from the side walls of the opening in the interconnect layer,
wherein the acoustic resonator comprises a support on the interconnect layer, the support including at least one bilayer assembly comprising a layer of high-acoustic-impedance material and a layer of low-acoustic-impedance material made of a low-electrical-permittivity material,
wherein the low-acoustic-impedance material comprises a porous SiOC material including pores filled with Argon.
14. The circuit according to claim 13 , wherein a bottom portion of the acoustic resonator supporting a first of the active elements is placed on the set of interconnects.
15. The circuit according to claim 13 , wherein a bottom portion of the acoustic resonator supporting a first of the active elements is embodied in the set of interconnects.
16. The circuit according to claim 13 , wherein the decoupling layer comprises at least a layer of low-acoustic-impedance material.
17. The circuit according to claim 13 , wherein the high-acoustic-impedance material comprises at least one material selected in the group consisting of: aluminum nitride, copper, nickel, tungsten, gold, platinum, molybdenum.
18. The circuit of claim 13 , the decoupling layer, comprising:
at least one assembly positioned between a first and second acoustic resonators, comprising:
a first layer of low-acoustic-impedance material having a first acoustic impedance; and
a second layer of low-acoustic-impedance material having a second acoustic impedance.
19. The circuit according to claim 18 , wherein the first layer of low-acoustic-impedance material comprises a layer of SiOC.
20. The circuit according to claim 19 , wherein the first layer of low-acoustic-impedance material comprises a layer at least 90% SiOC in weight.
21. The circuit according to claim 19 , wherein the second layer of low-acoustic-impedance material comprises a layer of porous SiOC including pores filled with Argon.
22. The circuit of claim 13 , the decoupling layer, comprising:
at least one assembly positioned between a first and second acoustic resonators, comprising:
a first and second layers of low-acoustic-impedance material having a first acoustic impedance;
a third layer of low-acoustic-impedance material having a second acoustic impedance.
23. The circuit according to claim 22 , wherein at least one of the layers of low-acoustic-impedance material comprises a layer of SiOC.
24. The circuit according to claim 23 , wherein the at least one layer of low-acoustic-impedance material comprises a layer at least 90% SiOC in weight.
25. The circuit according to claim 23 , wherein at least one other layer of low-acoustic-impedance material comprises a layer of porous SiOC including pores filled with Argon.
26. The circuit according to claim 22 , wherein the third layer is a middle layer between the first and second layers.
27. The circuit according to claim 26 , wherein the second acoustic impedance is higher than the first acoustic impedance.
28. The circuit of claim 13 , the decoupling layer, comprising:
at least one assembly positioned between a first and second acoustic resonators, comprising:
a first layer of low-acoustic-impedance material having a first acoustic impedance;
a second layer of low-acoustic-impedance material having a second acoustic impedance;
a layer of high-acoustic-impedance material.
29. The circuit according to claim 28 , wherein at least one of the first and second layers of low-acoustic-impedance material comprises a layer of SiOC.
30. The circuit according to claim 29 , wherein the at least one layer of low-acoustic-impedance material comprises a layer at least 90% SiOC in weight.
31. The circuit according to claim 29 , wherein the other of the first and second layers of low-acoustic-impedance material comprises a layer of porous SiOC including pores filled with Argon.
32. The circuit according to claim 28 , wherein the third layer is a middle layer between the first and second layers.
33. The circuit according to claim 28 , wherein the second acoustic impedance is higher than the first acoustic impedance.
34. The circuit according to claim 28 , wherein the first and second acoustic impedances are the same.
35. An acoustic resonator, comprising:
a substrate;
an interconnect layer above the substrate;
a first, second and third active elements;
a support positioned under the first active element comprising a first high acoustic impedance layer and a first low acoustic impedance layer, the support being embodied in the interconnect layer and the low acoustic impedance layer comprising a porous SiOC material having pores filled with Argon;
a first decoupling assembly positioned between the first and second active elements comprising plural layers of acoustic-impedance material; and
a second decoupling assembly positioned between the second and third active elements comprising plural layers of acoustic-impedance material.
36. The resonator of claim 35 wherein at least one of the first and second decoupling assemblies comprises:
a first layer of low-acoustic-impedance material having a first acoustic impedance; and
a second layer of low-acoustic-impedance material having a second acoustic impedance.
37. The resonator of claim 35 wherein at least one of the first and second decoupling assemblies comprises:
a first layer of low-acoustic-impedance material having a first acoustic impedance;
a second layer of low-acoustic-impedance material having a second acoustic impedance; and
a layer of high-acoustic-impedance material.