Granted Patent B2

US 12,283,937 · App. 17/471,604 · Granted Apr 22, 2025

Inventors: Benfeng Zhang (Moriguchi, JP); Jiansong Liu (Irvine, CA); Benjamin Paul Abbott (Irvine, CA); Kwang Jae Shin (Yongin, KR); Alexandre Augusto Shirakawa (Cardiff by the Sea, CA)

Assignee: Skyworks Global Pte. Ltd.

H03H9/02118H03F3/19H03H9/0014H03H9/02015H03H9/0504H03H9/13H03H9/132H03H9/171H03H9/173H03H9/54H03H9/568H04B1/40H03F2200/451

Abstract

Claims (28)

1. A bulk acoustic wave device with a multi-gradient raised frame, the bulk acoustic wave device comprising:

a first electrode;

a second electrode;

a piezoelectric layer positioned between the first electrode and the second electrode; and

a multi-gradient raised frame structure configured to cause lateral energy leakage from a main acoustically active region of the bulk acoustic wave device to be reduced, the multi-gradient raised frame structure being tapered on opposing sides, the multi-gradient raised frame structure including a first raised frame layer and a second raised frame layer, the second raised frame layer extending beyond the first raised frame layer on the opposing sides, the main acoustically active region being free from the first raised frame layer and the second raised frame layer, and the bulk acoustic wave device being configured to generate a bulk acoustic wave.

2. The bulk acoustic wave device of claim 1 wherein the multi-gradient raised frame structure surrounds the main acoustically active region of the bulk acoustic wave device in plan view.

3. The bulk acoustic wave device of claim 1 wherein the multi-gradient raised frame structure has a non-gradient portion between two gradient portions.

4. The bulk acoustic wave device of claim 1 wherein the multi-gradient raised frame structure consists essentially of gradient portions.

5. The bulk acoustic wave device of claim 1 wherein the bulk acoustic wave device is a film bulk acoustic resonator.

6. The bulk acoustic wave device of claim 1 wherein the opposing sides of the multi-gradient raised frame structure both vertically overlap with the first electrode and the second electrode over an acoustic reflector, and a first side of the opposing sides is between a second side of the opposing sides and the main acoustically active region of the bulk acoustic wave device.

7. The bulk acoustic wave device of claim 1 wherein the first raised frame layer includes an oxide.

8. The bulk acoustic wave device of claim 1 wherein the first raised frame layer has a lower acoustic impedance than at least one of the piezoelectric layer or the second raised frame layer.

9. The bulk acoustic wave device of claim 1 wherein the first raised frame layer is an oxide layer, and the second raised frame layer is metallic.

10. The bulk acoustic wave device of claim 1 wherein the first raised frame layer is a silicon dioxide layer, and the second raised frame layer is metallic.

11. The bulk acoustic wave device of claim 1 wherein the first raised frame layer is positioned between the first and second electrodes.

12. The bulk acoustic wave device of claim 11 wherein the second electrode is positioned between the first and second raised frame layers.

13. The bulk acoustic wave device of claim 1 wherein the second raised frame layer has a first taper angle on a first side and a second taper angle on a second side, and the first and second taper angles are in a range from 5 degrees to 45 degrees.

14. The bulk acoustic wave device of claim 1 wherein the multi-gradient raised frame structure is a convex structure relative to the piezoelectric layer.

15. An acoustic wave filter with a multi-gradient raised frame bulk acoustic wave device, the acoustic wave filter comprising:

a bulk acoustic wave device including a first electrode, a second electrode, a piezoelectric layer positioned between the first electrode and the second electrode, and a multi-gradient raised frame structure configured to cause lateral energy leakage from a main acoustically active region of the bulk acoustic wave device to be reduced, the multi-gradient raised frame structure being tapered on opposing sides, the multi-gradient raised frame structure including a first raised frame layer and a second raised frame layer, the second raised frame layer extending beyond the first raised frame layer on the opposing sides, the main acoustically active region being free from the first raised frame layer and the second raised frame layer; and

at least one additional acoustic wave device, the bulk acoustic wave device and the at least one additional acoustic wave device together arranged to filter a radio frequency signal.

16. The acoustic wave filter of claim 15 wherein at least one additional acoustic wave device includes a second bulk acoustic wave device that includes a second multi-gradient raised frame structure that is tapered on opposing sides.

17. The acoustic wave filter of claim 15 wherein the first raised frame layer includes an oxide, and the second raised frame layer is metallic.

18. A wireless communication device comprising:

an acoustic wave filter including a bulk acoustic wave device, the bulk acoustic wave device including a first electrode, a second electrode, a piezoelectric layer positioned between the first electrode and the second electrode, and a multi-gradient raised frame structure configured to cause lateral energy leakage from a main acoustically active region of the bulk acoustic wave device to be reduced, the multi-gradient raised frame structure being tapered on opposing sides, the multi-gradient raised frame structure including a first raised frame layer and a second raised frame layer, the second raised frame layer extending beyond the first raised frame layer on the opposing sides, the main acoustically active region being free from the first raised frame layer and the second raised frame layer; and

an antenna operatively coupled to the acoustic wave filter.

19. The wireless communication device of claim 18 wherein the wireless communication device is a mobile phone.

20. The wireless communication device of claim 18 wherein the acoustic wave filter is included in a multiplexer.

Assignments (1)

Continuity (2)

References Cited (85)