Acoustic wave devices with multi-layer piezoelectric substrate
AssigneeSkyworks Solutions, Inc.
InventorsRei Goto, Hironori Fukuhara
Life of this patent
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Abstract
An acoustic wave device has a substrate, an optional functional layer disposed over at least a portion of the substrate, a piezoelectric layer disposed over at least a portion of the functional layer and/or substrate, and an interdigital transducer electrode disposed on the piezoelectric layer. The piezoelectric layer has an outer edge spaced inward of an outer edge of the substrate, the outer edge of the piezoelectric layer being tapered at an angle relative to a surface of the substrate to thereby reduce an acoustic reflection magnitude at said outer edge of the piezoelectric layer.
Claims24
An acoustic wave device comprising:
- a substrate,
- a functional layer disposed over at least a portion of the substrate;
- a piezoelectric layer disposed over at least a portion of the functional layer;
- and
- an interdigital transducer electrode disposed on the piezoelectric layer, the piezoelectric layer has an outer edge spaced inward of an outer edge of the substrate, the outer edge of the piezoelectric layer tapered at an angle relative to a surface of the substrate to thereby reduce an acoustic reflection magnitude at said outer edge of the piezoelectric layer, and the functional layer having an outer lateral edge that is spaced inward of the outer edge of the substrate, tapered at the angle relative to the surface of the substrate, and aligned and coplanar with the outer edge of the piezoelectric layer.
A radio frequency module comprising:
- a package substrate;
- an acoustic wave device including a substrate, a functional layer disposed over at least a portion of the substrate, a piezoelectric layer disposed over at least a portion of the functional layer, and an interdigital transducer electrode disposed on the piezoelectric layer, the piezoelectric layer having an outer edge spaced inward of an outer edge of the substrate, the outer edge of the piezoelectric layer being tapered at an angle relative to a surface of the substrate to thereby reduce an acoustic reflection magnitude at said outer edge of the piezoelectric layer, and the functional layer having an outer lateral edge that is spaced inward of the outer edge of the substrate, tapered at the angle relative to the surface of the substrate, and aligned and coplanar with the outer edge of the piezoelectric layer;
- and
- additional circuitry, the acoustic wave device and additional circuitry disposed on the package substrate.
A wireless communication device comprising:
- an antenna;
- and
- a front end module including one or more acoustic wave devices configured to filter a radio frequency signal associated with the antenna, each acoustic wave device including a substrate, a functional layer disposed over at least a portion of the substrate, a piezoelectric layer disposed over at least a portion of the functional layer, and an interdigital transducer electrode disposed on the piezoelectric layer, the piezoelectric layer having an outer edge spaced inward of an outer edge of the substrate, the outer edge of the piezoelectric layer being tapered at an angle relative to a surface of the substrate to thereby reduce an acoustic reflection magnitude at said outer edge of the piezoelectric layer, and the functional layer having an outer lateral edge that is spaced inward of the outer edge of the substrate, tapered at the angle relative to the surface of the substrate, and aligned and coplanar with the outer edge of the piezoelectric layer.
Dependencies are inferred from the claim text.