Resonator with intrinsic second harmonic cancellation
A resonator may include a first electrode, a second electrode, and a piezoelectric material between the first electrode and the second electrode, where the piezoelectric material is formed by fabricating the piezoelectric material with a compression axis vector (C-axis vector) oriented along a first direction and applying an electric field across the piezoelectric material to modify a direction of the C-axis vector to be oriented along a second direction. The second direction may be antiparallel to the first direction.
1. A resonator comprising:
a first electrode;
a second electrode; and
a piezoelectric material between the first electrode and the second electrode, wherein the piezoelectric material is formed by:
fabricating the piezoelectric material with a compression axis vector (C-axis vector) oriented along a first direction, the piezoelectric material being doped with one or more dopant materials selected to lower an electric field strength for modifying the C-axis vector to a range of values lower than a breakdown threshold; and
applying an electric field across the piezoelectric material to modify a direction of the C-axis vector to be oriented along a second direction, wherein the second direction is antiparallel to the first direction.
2. The resonator of claim 1 , further comprising:
an additional piezoelectric material having an additional C-axis vector oriented along the first direction, wherein the piezoelectric material and the additional piezoelectric material are disposed between the first and second electrodes.
3. The resonator of claim 2 , further comprising:
a third electrode disposed between the piezoelectric material and the additional piezoelectric material.
4. The resonator of claim 1 , wherein the piezoelectric material comprises:
a base material doped with the one or more dopant materials.
5. The resonator of claim 4 , wherein the base material includes aluminum nitride, wherein the one or more dopant materials include at least one of a rare earth metal or boron.
6. The resonator of claim 4 , wherein the base material includes aluminum nitride, wherein the one or more dopant materials include scandium with a concentration of less than approximately 35%.
7. The resonator of claim 1 , wherein the resonator operates at a frequency equal to or greater than 6 GHz.
8. The resonator of claim 1 , wherein applying the electric field across the piezoelectric material to modify the direction of the C-axis vector from the first direction to the second direction comprises:
fabricating one or more electrical pathways from the first electrode to an electrical contact;
applying the voltage between the electrical contact and at least one of the second electrode or an additional electrode to generate the electric field; and
severing at least one of the one or more electrical pathways.
9. A circuit comprising:
one or more resonators, wherein at least one of the one or more resonators comprises:
a first electrode;
a second electrode; and
a piezoelectric material between the first electrode and the second electrode, wherein the piezoelectric material is formed by:
fabricating the piezoelectric material with a compression axis vector (C-axis vector) oriented along a first direction; and
applying an electric field across the piezoelectric material to modify a direction of the C-axis vector to be oriented along a second direction, wherein the second direction is different than the first direction;
wherein the piezoelectric material is doped with one or more dopant materials selected to lower an electric field strength for modifying the C-axis vector to a range of values lower than a breakdown threshold.
10. The circuit of claim 9 , wherein the circuit comprises:
a filter.
11. The circuit of claim 10 , wherein the filter operates at a frequency equal to or greater than 6 GHz.
12. The circuit of claim 9 , further comprising:
an additional piezoelectric material having an additional C-axis vector oriented along the first direction, wherein the piezoelectric material and the additional piezoelectric material are disposed between the first and second electrodes.
13. The circuit of claim 12 , further comprising:
a third electrode disposed between the piezoelectric material and the additional piezoelectric material.
14. The circuit of claim 9 , wherein the piezoelectric material comprises:
a base material doped with the one or more dopant materials.
15. The resonator of claim 14 , wherein the base material includes aluminum nitride, wherein the one or more dopant materials include at least one of a rare earth metal or boron.
16. The resonator of claim 14 wherein the base material includes aluminum nitride, wherein the one or more dopant materials include scandium with a concentration of less than approximately 35%.
17. A method comprising:
fabricating a first electrode;
fabricating a piezoelectric material with a compression axis vector (C-axis vector) oriented along a first direction;
applying an electric field across the piezoelectric material to modify a direction of the C-axis vector from the first direction to a second direction, wherein the second direction is antiparallel to the first direction; and
fabricating a second electrode, wherein the piezoelectric material is disposed between the first electrode and the second electrode;
wherein the piezoelectric material being doped with one or more dopant materials selected to lower an electric field strength for modifying the C-axis vector to a range of values lower than a breakdown threshold.
18. The method of claim 17 , further comprising:
fabricating an additional piezoelectric material having an additional C-axis vector oriented along the first direction.
19. The method of claim 18 , further comprising:
fabricating a third electrode, wherein the additional piezoelectric material is disposed between the second electrode and the third electrode.
20. The method of claim 18 , wherein the piezoelectric material and the additional piezoelectric material are disposed between the first electrode and the second electrode.