Title:
SURFACE ACOUSTIC WAVE DEVICE, AND FILTER DEVICE
Document Type and Number:
WIPO Patent Application WO/2020/261978
Kind Code:
A1
Abstract:
The objective of the present invention is to provide a surface acoustic wave device which has excellent electric power resistance and linearity, and with which unwanted waves can be suppressed. A surface acoustic wave device 1 is provided with: a piezoelectric substrate 2 comprising θ° rotated Y-cut X-propagating LiNbO3 having a cut angle of θ; an IDT electrode 3 which is provided on the piezoelectric substrate 2 and which includes a plurality of electrode fingers; and a dielectric film 4 provided on the piezoelectric substrate 2 to cover the IDT electrode 3. The IDT electrode 3 includes a main electrode layer 3a, and an electrically conductive auxiliary layer 3b. The main electrode layer 3a is positioned on the piezoelectric substrate 2 side of the electrically conductive auxiliary layer 3b. The main component of the main electrode layer 3a is Pt. The relationships in formula (1) and formulas (2A) to (2D) are satisfied when h is the film thickness of the main electrode layer 3a, H is the film thickness of the dielectric film 4, and λ is a wavelength defined by the electrode finger pitch of the IDT electrode 3.
Inventors:
MIMURA MASAKAZU (JP)
Application Number:
PCT/JP2020/022676
Publication Date:
December 30, 2020
Filing Date:
June 09, 2020
Export Citation:
Assignee:
MURATA MANUFACTURING CO (JP)
International Classes:
H03H9/145; H03H9/25
Domestic Patent References:
| WO2011158445A1 | 2011-12-22 | |||
| WO2018116602A1 | 2018-06-28 | |||
| WO2008108215A1 | 2008-09-12 |
Foreign References:
| JP2008235950A | 2008-10-02 |
Attorney, Agent or Firm:
MIYAZAKI & METSUGI (JP)
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