Title:
ELASTIC WAVE DEVICE
Document Type and Number:
WIPO Patent Application WO/2022/163865
Kind Code:
A1
Abstract:
Provided is an elastic wave device in which ripples in a frequency characteristic can be suppressed. An elastic wave device 10 according to the present invention constitutes a filter device having a pass band and comprises a laminated substrate 13 having a first layer 13A and a second layer 13B, the first layer 13A being laminated on the second layer 13B, a piezoelectric layer 14 laminated on the first layer 13A of the laminated substrate 13, and exciting electrodes provided on the piezoelectric layer 14. The first layer 13A is a dielectric layer and is included in an intermediate layer laminated on the piezoelectric layer. Where the speed of sound of a transverse wave propagating in the first layer 13A is v, the frequency included in the pass band of the filter device is f, the wavelength derived by v/f is λ, the acoustic impedance of the piezoelectric layer 14 is Zp, the acoustic impedance of the first layer 13A is Zd, the acoustic impedance of the second layer 13B is Zs, the thickness of the first layer 13A is td, and any one of the natural numbers is n, the combinations of the thickness td and the relationship between the magnitudes of the acoustic impedances of the piezoelectric layer 14, first layer 13A and second layer 13B are such as shown in Table 1.
Inventors:
ISHII YUTA (JP)
Application Number:
PCT/JP2022/003811
Publication Date:
August 04, 2022
Filing Date:
February 01, 2022
Export Citation:
Assignee:
MURATA MANUFACTURING CO (JP)
International Classes:
H03H9/25
Domestic Patent References:
| WO2019123812A1 | 2019-06-27 | |||
| WO2016147687A1 | 2016-09-22 |
Foreign References:
| JP2019140456A | 2019-08-22 | |||
| JP2010154505A | 2010-07-08 |
Attorney, Agent or Firm:
OSAKA FRONT (JP)
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