Electroacoustic component operating with guided bulk acoustic waves
View Patent ↗An electroacoustic component operates with guided acoustic waves and includes a first substrate, a second substrate, a metallic layer and an intermediate layer. The first substrate (S 1 ) is made from a monocrystalline LiTaO 3 . The metallic layer is arranged between the first substrate and the intermediate layer. The intermediate layer is arranged between the metallic layer and the second substrate. The crystal section of monocrystalline LiTaO 3 is chosen such that for the second Euler angle μ: −100°≦μ≦−40° or −160°≦μ≦−130°. For the first Euler angle λ, preferably λ=0° and for the third Euler angle θ, −10°≦θ≦10°.
1. An electroacoustic component operating with guided bulk acoustic waves, the component comprising:
a first substrate made from a monocrystalline LiTaO 3 ;
a second substrate;
a metallic layer; and
an intermediate layer;
wherein the metallic layer is arranged between the first substrate and the intermediate layer;
wherein the intermediate layer is arranged between the metallic layer and the second substrate; and
wherein a crystal section of monocrystalline LiTaO 3 is chosen such that
for a first Euler angle λ, λ=0°,
for a second Euler angle angle μ: −100°≦μ≦−40° or −160°≦μ≦−130°, and
for the third Euler angle θ, −10°≦θ<0°or θ=0° or 0°<θ≦10°; and
wherein the electroacoustic components operates with guided bulk acoustic waves.
2. The component according to claim 1 , wherein −100°≦μ≦−40°.
3. The component according to claim 2 , wherein a horizontally polarized shear wave can be excited.
4. The component according to claim 3 , wherein −44°≦μ≦−64°.
5. The component according to claim 2 , wherein −85°≦μ≦−65°.
6. The component according to claim 1 , wherein −160°≦μ≦−130°.
7. The component according to claim 6 , in which a Rayleigh wave can be excited.
8. The component according to claim 7 , wherein −146°≦μ≦−131°.
9. The component according to claim 1 , wherein the metallic layer is arranged on the first substrate and has electrodes for exciting an acoustic wave with wavelength λ 0 .
10. The component according to claim 9 , wherein the metallic layer comprises a W-layer.
11. The component according to claim 9 , wherein the metallic layer comprises an Al-layer.
12. The component according to claim 1 , wherein the intermediate layer comprises a planarization layer.
13. The component according to claim 12 , wherein the intermediate layer comprises SiO x with 1.6≦x≦2.1.
14. The component according to claim 12 , wherein the intermediate layer has a thickness between 20% and 200% with respect to wavelength λ 0 , wherein λ 0 comprises an acoustic wavelength at which the first substrate is excited.
15. The component according to claim 12 , wherein the second substrate comprises Si.
16. The component according to claim 12 , wherein the first substrate and the second substrate each have a thickness of at least 10λ 0 , wherein λ 0 comprises an acoustic wavelength at which the first substrate is excited.
17. The component according to claim 1 , wherein −10°≦θ<0°.
18. The component according to claim 1 , wherein θ=0°.
19. The component according to claim 1 , wherein or 0°<θ≦10°.