Boundary acoustic wave device
AssigneeMurata Manufacturing Co., Ltd.
InventorTakashi YAMANE
Life of this patent
Estimating the term…
Abstract
A boundary acoustic wave device that has a three-medium structure and that prevents a high-order mode spurious response includes a piezoelectric substrate, a first dielectric layer laminated on the piezoelectric substrate, a second dielectric layer laminated on the first dielectric layer, and an IDT electrode provided at an interface between the piezoelectric substrate and the first dielectric layer. The boundary acoustic wave device utilizes a Stoneley wave that propagates along the interface. Where V1 denotes an acoustic velocity of a slow transversal bulk wave in the piezoelectric substrate and Va denotes an acoustic velocity at an anti-resonant point in a high-order mode of the Stoneley wave, Va>V1 is satisfied.
Claims8
A boundary acoustic wave device comprising:
- a piezoelectric substrate;
- a first dielectric layer laminated on the piezoelectric substrate;
- a second dielectric layer laminated on the first dielectric layer;
- and
- an IDT electrode provided at an interface between the piezoelectric substrate and the first dielectric layer;
- wherein
- the boundary acoustic wave device utilizes a Stoneley wave that propagates along the interface, and Va>V1 is satisfied, where V1 denotes an acoustic velocity of a slow transversal bulk wave in the piezoelectric substrate and Va denotes an acoustic velocity at an anti-resonant point in a higher-order mode of the Stoneley wave.
Dependencies are inferred from the claim text.