Boundary acoustic wave device
AssigneeSkyworks Solutions, Inc.
InventorsHiroyuki Nakamura, Rei Goto, Keiichi Maki
Life of this patent
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Abstract
Aspects of this disclosure relate to an acoustic wave device that includes high velocity layers on opposing sides of a piezoelectric layer. A temperature compensation layer can be positioned between one of the high velocity layers and the piezoelectric layer. The acoustic wave device can be arranged to generate a boundary acoustic wave having a higher velocity than a respective acoustic velocity of each of the high velocity layers.
Claims20
An acoustic wave device comprising:
- a piezoelectric layer;
- an interdigital transducer electrode on the piezoelectric layer;
- high velocity layers on opposing side of the piezoelectric layer, the high velocity layers including a first high velocity layer having a first acoustic velocity and a second high velocity layer having a second acoustic velocity;
- a temperature compensation layer in physical contact with the interdigital transducer electrode and positioned between the first high velocity layer and the piezoelectric layer;
- and
- an adhesion layer within the temperature compensation layer such that the adhesion layer is positioned between a first portion of the temperature compensation layer and a second portion of the compensation layer, the adhesion layer arranged to enhance power durability of the acoustic wave device, the acoustic wave device being configured to generate a boundary acoustic wave such that acoustic energy is concentrated at an interface of the piezoelectric layer and the temperature compensation layer, the boundary acoustic wave having a velocity that is less than both the first acoustic velocity and the second acoustic velocity, the boundary acoustic wave having a wavelength of λ, and the thickness of the second high velocity layer being at least 10λ.
An acoustic wave device comprising:
- a piezoelectric layer;
- an interdigital transducer electrode on the piezoelectric layer;
- silicon layers on opposing sides of the piezoelectric layer, the silicon layers including a first silicon layer and a second silicon layer;
- and
- a silicon dioxide layer disposed between the first silicon layer and the piezoelectric layer, the acoustic wave device being configured to generate a boundary acoustic wave such that maximum displacement in an acoustic displacement distribution is centered at an interface of the piezoelectric layer and the silicon dioxide layer, the boundary acoustic wave having a wavelength of λ, the second silicon layer having a thickness sufficient to maintain mechanical durability of the acoustic wave device, the thickness of the second silicon layer being at least 10λ, and the acoustic wave device having a thickness in a range from 10 micrometers to 100 micrometers.
An acoustic wave filter comprising an acoustic wave device that includes a piezoelectric layer, an interdigital transducer electrode on the piezoelectric layer, silicon layers on opposing sides of the piezoelectric layer, a silicon dioxide layer disposed between one of the silicon layers and the piezoelectric layer, and an adhesion layer within the silicon dioxide layer, the acoustic wave device being configured to generate a boundary acoustic wave such that acoustic energy is concentrated at an interface of the piezoelectric layer and the silicon dioxide layer, at least one of the silicon layers having a thickness sufficient to maintain mechanical durability of the acoustic wave device, and the acoustic wave filter configured to filter a radio frequency signal.
Dependencies are inferred from the claim text.