Acoustic resonator devices operating at high-order modes

Patent metadata

Field	Value
Publication number	US-2025141425-A1
Application number	US-202318498011-A
Country	US
Kind code	A1
Filing date	Oct 30, 2023
Priority date	Oct 30, 2023
Publication date	May 1, 2025
Grant date	—

Abstract

The subject technology is related to acoustic resonators. More specifically, an embodiment of the subject technology provides an acoustic resonator device that includes a piezoelectric layer disposed between a first electrode and a second electrode. The total thickness of the first electrode, the second electrode, and the third electrode allows the device to operate according to a second (or higher order) thickness extension mode. There are other embodiments as well.

First claim

What is claimed is:

1 . An acoustic resonator device comprising:
a first electrode characterized by a first thickness, the first electrode comprising a first metal; a second electrode characterized by a second thickness, the second electrode comprising a second metal; and a first piezoelectric layer disposed between the first electrode and the second electrode, the first piezoelectric being characterized by a third thickness; wherein:
a total thickness comprising the first thickness and the second thickness and the third thickness is associated with two or more stress half-waves; and
the acoustic resonator device is characterized by an operating frequency of at least 5 GHz.

2 . The acoustic resonator device of claim 1 , wherein the first thickness is different from the second thickness.

3 . The acoustic resonator device of claim 1 , wherein the first thickness is greater than the second thickness, and the first thickness is associated with a first stress half-wave.

4 . The acoustic resonator device of claim 1 , wherein the total thickness is associated with three stress half-waves.

5 . The acoustic resonator device of claim 1 , wherein the acoustic resonator device operates in a second thickness extension mode or a third thickness extension mode.

6 . The acoustic resonator device of claim 1 , wherein:
the first electrode further comprises a third metal, a distance between the first metal and the first piezoelectric layer is greater than a distance between the third metal and the first piezoelectric layer.

7 . The acoustic resonator device of claim 6 , wherein the first metal is characterized by a first acoustic impedance, the third metal is characterized by a second acoustic impedance, and the second acoustic impedance is greater than the first acoustic impedance.

8 . The acoustic resonator device of claim 6 , wherein the first metal is characterized by a greater thickness than the third metal.

9 . The acoustic resonator device of claim 1 , further comprising a second piezoelectric layer disposed between the first electrode and the first piezoelectric layer, the first piezoelectric layer and the second piezoelectric layer being characterized by different orientations;
wherein the total thickness is associated with three or more stress half-waves.

10 . An acoustic resonator device comprising:
a first electrode characterized by a first thickness, the first electrode comprising a first metal; a second electrode characterized by a second thickness, the second electrode comprising a second metal; and a first piezoelectric layer disposed between the first electrode and the second electrode, the first piezoelectric layer being characterized by a third thickness; wherein:
a total thickness comprising the first thickness;
the second thickness and the third thickness are associated with two or more stress half-waves; and
the acoustic resonator device operates in a second thickness extension mode or higher.

11 . The acoustic resonator device of claim 10 , wherein the second thickness extension mode is characterized by an operating frequency of at least 6 GHz.

12 . The acoustic resonator device of claim 10 , wherein the second electrode further comprises a third metal.

13 . The acoustic resonator device of claim 10 , further comprising a third electrode and a second piezoelectric layer, the second piezoelectric layer being disposed between the third electrode and the first electrode.

14 . An acoustic resonator device comprising:
a first electrode characterized by a first thickness, the first electrode comprising a first metal; a second electrode characterized by a second thickness, the second electrode comprising a second metal; a third electrode characterized by a third thickness, the third electrode comprising a third metal; a first piezoelectric layer disposed between the first electrode and the second electrode, the first piezoelectric being characterized by a fourth thickness; and a second piezoelectric layer disposed between the second electrode and the third electrode, the second piezoelectric being characterized by a fifth thickness; wherein the acoustic resonator device operates in a third thickness extension mode or higher.

15 . The acoustic resonator device of claim 14 , wherein the first metal is characterized by a first acoustic impedance, the second metal is characterized by a second acoustic impedance, and the second acoustic impedance is greater than the first acoustic impedance.

16 . The acoustic resonator device of claim 14 , wherein the first piezeoelectric layer comprises an aluminum compound.

17 . The acoustic resonator device of claim 14 , wherein the first thickness is different from the second thickness.

18 . The acoustic resonator device of claim 14 , wherein the first thickness is greater than the second thickness, and the first thickness is associated with a first stress half-wave.

19 . The acoustic resonator device of claim 14 , wherein the first piezoelectrical layer is characterized by a different orientation from the second piezoelectrical layer.

20 . The acoustic resonator device of claim 14 , wherein the first thickness matches the third thickness.

Assignees

• Avago Tech Int Sales Pte Lid

Inventors

• Marksteiner Stephan
• Nessler Winfried
• Yatsenko Andriy

Classifications

• H03H9/02007

  of bulk acoustic wave devices · CPC title

• H03H9/131

  consisting of a multilayered structure · CPC title

• H03H9/171 Primary

  implemented with thin-film techniques, i.e. of the film bulk acoustic resonator [FBAR] type · CPC title

• H03H9/173

  Air-gaps · CPC title

• H03H9/132 Primary

  characterized by a particular shape · CPC title