Assembly with piezoelectric layer with embedded interdigital transducer electrode
An acoustic wave device assembly is disclosed. The acoustic wave device assembly can include a first acoustic wave device that includes a first substrate, a first piezoelectric layer, a first solid acoustic mirror that is disposed between the first substrate and the first piezoelectric layer, and a first interdigital transducer electrode that is embedded in the piezoelectric layer. The acoustic wave device assembly can include a second acoustic wave device that includes a second substrate, a second piezoelectric layer, a second solid acoustic mirror that is disposed between the second substrate and the second piezoelectric layer, and a second interdigital transducer electrode that is in contact with the second piezoelectric layer. The second acoustic wave device is stacked over the first acoustic wave device. The first acoustic wave device and the second acoustic wave device are spaced by a spacer assembly such that a cavity is formed between the first acoustic wave device and the second acoustic wave device.
1 . An acoustic wave device assembly comprising:
a first acoustic wave device including a first substrate, a first piezoelectric layer, a first solid acoustic mirror disposed between the first substrate and the first piezoelectric layer, and a first interdigital transducer electrode embedded in the first piezoelectric layer; and
a second acoustic wave device including a second substrate, a second piezoelectric layer, a second solid acoustic mirror disposed between the second substrate and the second piezoelectric layer, and a second interdigital transducer electrode in contact with the second piezoelectric layer, the second acoustic wave device being stacked with the first acoustic wave device, the first acoustic wave device and the second acoustic wave device being spaced by a spacer assembly such that a cavity is formed between the first acoustic wave device and the second acoustic wave device, the second solid acoustic mirror closer to the cavity than the second piezoelectric layer, and a third solid acoustic mirror disposed between the second piezoelectric layer and a third substrate.
2 . The acoustic wave device assembly of claim 1 wherein the second interdigital transducer electrode is embedded in the second piezoelectric layer.
3 . The acoustic wave device assembly of claim 1 wherein the first interdigital transducer electrode is completely embedded in the first piezoelectric layer such that the first interdigital transducer electrode is positioned closer to the cavity than to the first solid acoustic mirror.
4 . The acoustic wave device assembly of claim 1 wherein the first solid acoustic mirror includes alternating low impedance layers and high impedance layers that has a higher impedance than the low impedance layers of first solid acoustic mirror.
5 . The acoustic wave device assembly of claim 4 wherein the second solid acoustic mirror includes alternating low impedance layers and high impedance layers that has a higher impedance than the low impedance layers of second solid acoustic mirror.
6 . The acoustic wave device assembly of claim 5 wherein the low impedance layers of the first solid acoustic mirror and the low impedance layers of the second solid acoustic mirror have different thicknesses.
7 . The acoustic wave device assembly of claim 1 wherein the first piezoelectric layer and the second piezoelectric layer are positioned between the first and third substrates.
8 . The acoustic wave device assembly of claim 1 wherein the second substrate is disposed between the first and second piezoelectric layers.
9 . The acoustic wave device assembly of claim 1 wherein at least one of the first acoustic wave device or the second acoustic wave device is a laterally excited bulk acoustic wave resonator.
10 . The acoustic wave device assembly of claim 1 wherein at least one of the first acoustic wave device or the second acoustic wave device is a leaky longitudinal surface acoustic wave resonator.
11 . The acoustic wave device assembly of claim 1 wherein the first acoustic wave device has a single mirror structure and the second acoustic wave device has a double mirror structure.
12 . An acoustic wave device assembly comprising:
a first acoustic wave device including a first substrate, a first piezoelectric layer having a first portion and a second portion, a first solid acoustic mirror disposed between the first substrate and the first piezoelectric layer, and a first interdigital transducer electrode on the first portion of the first piezoelectric layer and covered by the second portion of the first piezoelectric layer; and
a second acoustic wave device including a second substrate, a second piezoelectric layer, a second solid acoustic mirror disposed between the second substrate and the second piezoelectric layer, and a second interdigital transducer electrode in contact with the second piezoelectric layer, the second acoustic wave device being stacked with the first acoustic wave device, the first acoustic wave device and the second acoustic wave device being spaced by a spacer assembly such that a cavity is formed between the first acoustic wave device and the second acoustic wave device, the second solid acoustic mirror closer to the cavity than the second piezoelectric layer, and a third solid acoustic mirror disposed between the second piezoelectric layer and a third substrate.
13 . The acoustic wave device assembly of claim 12 wherein the second interdigital transducer electrode is embedded in the second piezoelectric layer.
14 . The acoustic wave device assembly of claim 12 wherein a thickness of the first portion of the first piezoelectric layer is greater than a thickness of the second portion of the second piezoelectric layer.
15 . The acoustic wave device assembly of claim 12 wherein the first solid acoustic mirror includes alternating low impedance layers and high impedance layers that has a higher impedance than the low impedance layers of first solid acoustic mirror.
16 . The acoustic wave device assembly of claim 15 wherein the second solid acoustic mirror includes alternating low impedance layers and high impedance layers that has a higher impedance than the low impedance layers of second solid acoustic mirror.
17 . The acoustic wave device assembly of claim 16 wherein the low impedance layers of the first solid acoustic mirror and the low impedance layers of the second solid acoustic mirror have different thicknesses.
18 . The acoustic wave device assembly of claim 12 wherein the first piezoelectric layer and the second piezoelectric layer are positioned between the first and third substrates.
19 . The acoustic wave device assembly of claim 12 wherein the second substrate is disposed between the first and second piezoelectric layers.
20 . The acoustic wave device assembly of claim 12 wherein the first acoustic wave device has a single mirror structure and the second acoustic wave device has a double mirror structure.