Acoustic wave device
AssigneeMurata Manufacturing Co., Ltd.
InventorMinefumi Ouchi
Life of this patent
Estimating the term…
Abstract
An acoustic wave device includes a piezoelectric layer including first and second main surfaces facing each other, an IDT electrode on the first main surface and including first and second busbars facing each other and electrode fingers, a first conductor on the second main surface and facing the first busbar with the piezoelectric layer therebetween, and a support on the second main surface and supporting the piezoelectric layer. A cavity that opens towards the piezoelectric layer is provided in the support, and the first conductor is positioned inside the cavity. An electric potential of the first conductor is different from an electric potential to which the first busbar is connected.
Claims24
An acoustic wave device comprising:
- a piezoelectric layer including a first main surface and a second main surface that face each other;
- an IDT electrode on the first main surface of the piezoelectric layer and including a first busbar and a second busbar that face each other, and a plurality of electrode fingers;
- a first conductor on the second main surface of the piezoelectric layer and facing the first busbar with the piezoelectric layer interposed therebetween;
- a second conductor on the second main surface of the piezoelectric layer and facing the second busbar with the piezoelectric layer interposed therebetween;
- and
- a support on the second main surface of the piezoelectric layer and supporting the piezoelectric layer;
- wherein
- a cavity that opens towards the piezoelectric layer is provided in the support;
- the first conductor is positioned inside the cavity;
- an electric potential of the first conductor is different from an electric potential to which the first busbar is connected;
- the second conductor is positioned inside the cavity;
- a potential of the second conductor is different from a potential to which the second busbar is connected;
- and
- a capacitor is defined by the second conductor, the second busbar, and the piezoelectric layer.
An acoustic wave device comprising:
- a piezoelectric layer including a first main surface and a second main surface that face each other;
- an IDT electrode on the first main surface of the piezoelectric layer and including a first busbar and a second busbar that face each other, and a plurality of electrode fingers;
- a conductor on the second main surface of the piezoelectric layer and facing the first busbar with the piezoelectric layer interposed therebetween;
- and
- a support on the second main surface of the piezoelectric layer and supporting the piezoelectric layer;
- wherein
- a cavity that opens towards the piezoelectric layer is provided in the support;
- the conductor is positioned inside the cavity;
- an electric potential of the conductor is different from an electric potential to which the first busbar is connected;
- a through hole is provided in the piezoelectric layer;
- and
- the acoustic wave device further includes a lead-out wiring line connected to the conductor and extending through the through hole.
An acoustic wave device comprising:
- a piezoelectric layer including a first main surface and a second main surface that face each other;
- an IDT electrode on the first main surface of the piezoelectric layer and including a first busbar and a second busbar that face each other, and a plurality of electrode fingers;
- a conductor on the second main surface of the piezoelectric layer and facing the first busbar with the piezoelectric layer interposed therebetween;
- and
- a support on the second main surface of the piezoelectric layer and supporting the piezoelectric layer;
- wherein
- a cavity that opens towards the piezoelectric layer is provided in the support;
- the conductor is positioned inside the cavity;
- an electric potential of the conductor is different from an electric potential to which the first busbar is connected;
- the cavity includes a central cavity overlapping the plurality of electrode fingers in plan view and a lateral cavity overlapping the first busbar in plan view and positioned at a side of the central cavity;
- and
- the conductor is positioned inside the lateral cavity.
Dependencies are inferred from the claim text.