Elastic wave device
An elastic wave device making use of an SH plate wave propagating in LiNbO 3 substrates includes a LiNbO 3 substrate, IDT electrodes located on at least one surface of the LiNbO 3 substrate, and a support which is bonded to the LiNbO 3 substrate such that the support is located outside a region provided with the IDT electrodes and supports the LiNbO 3 substrate, wherein θ of the Euler angles (0°, θ, 0°) of the LiNbO 3 substrate ranges from about 92° to about 138° and the thickness of the LiNbO 3 substrate ranges from about 0.05λ to about 0.25λ, where λ is the wavelength determined by the pitch between electrode fingers of the IDT electrodes.
1. An elastic wave device comprising:
a LiNbO 3 substrate;
an IDT electrode located on at least one surface of the LiNbO 3 substrate; and
a support arranged on the LiNbO 3 substrate such that the support is located outside a region provided with the IDT electrode and supports the LiNbO 3 substrate; wherein
an elastic wave propagating in the LiNbO 3 substrate is an SH plate wave; and
θ of Euler angles (0°, θ, 0°) of the LiNbO 3 substrate ranges from about 92° to about 138° and a thickness of the LiNbO 3 substrate ranges from about 0.05λ to about 0.25λ, where λ is a wavelength determined by a pitch between electrode fingers of the IDT electrode.
2. The elastic wave device according to claim 1 , wherein the IDT electrode is made of a metal containing one of a plurality of metals shown in Table 1 below as a major component and have a thickness within a range specified in Table 1 depending on a type of the metal:
TABLE 1
Thickness of IDT electrode
Pt
More than 0 to 0.083λ or less
Au
More than 0 to 0.055λ or less
Cu
More than 0 to 0.11λ or less
Ni
More than 0 to 0.16λ or less
Al
More than 0 to 0.135λ or less.
3. The elastic wave device according to claim 1 , wherein the IDT electrode is made of a metal containing one of a plurality of metals shown in Table 2 below as a major component and a duty is within a range specified in Table 2 depending on a type of the metal:
TABLE 2
Duty
Pt
0.105 to 0.62
Au
0.105 to 0.585
Cu
0.11 to 0.645
Ni
0.11 to 0.655
Al
0.115 to 0.63.
4. The elastic wave device according to claim 2 , wherein the IDT electrode is made of a metal containing one of a plurality of metals shown in Table 2 below as a major component and a duty is within a range specified in Table 2 depending on a type of the metal:
TABLE 2
Duty
Pt
0.105 to 0.62
Au
0.105 to 0.585
Cu
0.11 to 0.645
Ni
0.11 to 0.655
Al
0.115 to 0.63.
5. The elastic wave device according to claim 1 , wherein the IDT electrode is located on both surfaces of the LiNbO 3 substrate, the IDT electrode is made of a metal containing one of a plurality of metals shown in Table 3 below as a major component, and a thickness of the IDT electrode is within a range specified in Table 3 depending on a type of the metal:
TABLE 3
Metal making
Thickness of single-side IDT
up electrode
electrodes
Pt
More than 0 to 0.14λ or less
Au
More than 0 to 0.067λ or less
Cu
More than 0 to 0.145λ or less
Ni
0.002λ to 0.20λ
Al
More than 0 to 0.125λ or less.
6. The elastic wave device according to claim 1 , wherein the IDT electrode is located on both surfaces of the LiNbO 3 substrate and a duty of the IDT electrode is within a range specified in Table 4 below depending on a type of a metal making up the IDT electrode:
TABLE 4
Metal making
up electrode
Duty
Pt
0.018 to 0.547
Au
0.018 to 0.523
Ni
0.018 to 0.597
Cu
0.018 to 0.567
Al
0.025 to 0.56.
7. The elastic wave device according to claim 5 , wherein the IDT electrode is located on both surfaces of the LiNbO 3 substrate and a duty of the IDT electrode is within a range specified in Table 4 below depending on a type of a metal making up the IDT electrode:
TABLE 4
Metal making
up electrode
Duty
Pt
0.018 to 0.547
Au
0.018 to 0.523
Ni
0.018 to 0.597
Cu
0.018 to 0.567
Al
0.025 to 0.56.
8. The elastic wave device according to claim 1 , wherein the support is a support substrate including a through-hole facing a region provided with the IDT electrode.
9. The elastic wave device according to claim 2 , wherein the support is a support substrate including a through-hole facing a region provided with the IDT electrode.
10. The elastic wave device according to claim 3 , wherein the support is a support substrate including a through-hole facing a region provided with the IDT electrode.
11. The elastic wave device according to claim 4 , wherein the support is a support substrate including a through-hole facing a region provided with the IDT electrode.
12. The elastic wave device according to claim 5 , wherein the support is a support substrate including a through-hole facing a region provided with the IDT electrode.
13. The elastic wave device according to claim 6 , wherein the support is a support substrate including a through-hole facing a region provided with the IDT electrode.
14. The elastic wave device according to claim 7 , wherein the support is a support substrate including a through-hole facing a region provided with the IDT electrode.
15. The elastic wave device according to claim 1 , wherein the IDT electrode is made of a metal containing a metal having a density between about 2.699×10 3 kg/m 3 to about 8.93×10 3 kg/m 3 as a major component.
16. The elastic wave device according to claim 2 , wherein the IDT electrode is made of a metal containing a metal having a density between about 2.699×10 3 kg/m 3 to about 8.93×10 3 kg/m 3 as a major component.
17. The elastic wave device according to claim 3 , wherein the IDT electrode is made of a metal containing a metal having a density between about 2.699×10 3 kg/m 3 to about 8.93×10 3 kg/m 3 as a major component.
18. The elastic wave device according to claim 4 , wherein the IDT electrode is made of a metal containing a metal having a density between about 2.699×10 3 kg/m 3 to about 8.93×10 3 kg/m 3 as a major component.
19. The elastic wave device according to claim 5 , wherein the IDT electrode is made of a metal containing a metal having a density between about 2.699×10 3 kg/m 3 to about 8.93×10 3 kg/m 3 as a major component.
20. The elastic wave device according to claim 6 , wherein the IDT electrode is made of a metal containing a metal having a density between about 2.699×10 3 kg/m 3 to about 8.93×10 3 kg/m 3 as a major component.