Electroacoustic resonator

Patent metadata

Field	Value
Publication number	US-12355424-B2
Application number	US-202217934131-A
Country	US
Kind code	B2
Filing date	Sep 21, 2022
Priority date	Sep 21, 2022
Publication date	Jul 8, 2025
Grant date	Jul 8, 2025

Abstract

Aspects of the disclosure relate to wireless communication, and high-frequency filters with resonators. One aspect is a device including first and second busbars, and electrode fingers coupled between the busbars, with electrode fingers extending different distances toward an opposite busbar such that a second end of each of the electrode fingers collectively form wave shapes. The device further includes pluralities of gap reflectors positioned between the wave shapes and a nearest busbar.

First claim

What is claimed is:

1. An electroacoustic resonator comprising:
a first busbar extending in a first direction;
a second busbar extending in the lateral direction;
a first plurality of electrode fingers coupled to the first busbar and extending in a second direction towards the second busbar without touching the second busbar, each of the first plurality of electrode fingers having a first end coupled to the first busbar and a second end, and each of the first plurality of electrode fingers extending a different distance toward the second busbar relative to adjacent electrode fingers of the first plurality of electrode fingers such that the second end of each of the first plurality of electrode fingers collectively form a first wave shape;
a second plurality of electrode fingers coupled to the second busbar and extending in a third direction toward the first busbar without touching the first busbar, each of the second plurality of electrode fingers having a first end coupled to the second busbar and a second end, and each of the second plurality of electrode fingers extending a different distance toward the first busbar relative to adjacent electrode fingers of the second plurality of electrode fingers such that the second end of each of the second plurality of electrode fingers collectively form a second wave shape, wherein the first plurality of electrode fingers and the second plurality of electrode fingers are interleaved;
a first plurality of gap reflectors substantially parallel to the first busbar, the first plurality of gap reflectors positioned between the first busbar and a curve associated with the second wave shape, wherein the first plurality of gap reflectors comprises a first group of at least one gap reflector having a first length in the first direction and a second group of at least one gap reflector having a second length different from the first length in the first direction; and
a second plurality of gap reflectors substantially parallel to the second busbar, the second plurality of gap reflectors positioned between the second busbar and a curve associated with the first wave shape, wherein the second plurality of gap reflectors comprises a third group of at least one gap reflector having the first length in the first direction and a fourth group of at least one gap reflector having the second length in the first direction.

2. The electroacoustic resonator of claim 1 , wherein:
the first plurality of electrode fingers comprise a first weighted section proximate to the first end of each of the first plurality of electrode fingers; and
the second plurality of electrode fingers comprise a first weighted section proximate to the first end of each of the second plurality of electrode fingers.

3. The electroacoustic resonator of claim 2 , wherein:
the first weighted section proximate to the first end of each of the first plurality of electrode fingers is positioned on the curve associated with the second wave shape; and
the first weighted section proximate to the first end of each of the second plurality of electrode fingers is positioned on the curve associated with the first wave shape.

4. The electroacoustic resonator of claim 3 , wherein:
each electrode finger of the first plurality of electrode fingers comprises a second weighted section at the second end; and
each electrode finger of the second plurality of electrode fingers comprises a second weighted section at the second end.

5. The electroacoustic resonator of claim 4 , wherein the first weighted section and the second weighted section of each of the first plurality of electrode fingers and the first weighted section and the second weighted section of each of the second plurality of electrode fingers each comprise a respective area of additional thickness compared with a respective center track portion of each corresponding electrode finger.

6. The electroacoustic resonator of claim 4 , wherein the first weighted section and the second weighted section of each of the first plurality of electrode fingers and the first weighted section and the second weighted section of each of the second plurality of electrode fingers each comprise a respective area of additional finger width compared with a respective center track portion of each corresponding electrode finger.

7. The electroacoustic resonator of claim 1 , further comprising:
a first end reflector at a first track end, the first end reflector comprising reflector fingers extending in a perpendicular direction from the first busbar to the second busbar;
a third plurality of electrode fingers coupled to the first busbar between the first plurality of electrode fingers or the second plurality of electrode fingers and the first end reflector, the third plurality of electrode fingers extending in the perpendicular direction towards the second busbar without touching the second busbar; and
a fourth plurality of electrode fingers coupled to the second busbar between the first plurality of electrode fingers or the second plurality of electrode fingers and the first end reflector, the fourth plurality of electrode fingers extending in the perpendicular direction towards the first busbar without touching the first busbar, wherein the third plurality of electrode fingers are interleaved with the fourth plurality of electrode fingers.

8. The electroacoustic resonator of claim 7 , wherein:
the third plurality of electrode fingers each further comprise a first weighted section, wherein each first weighted section of the third plurality of electrode fingers is approximately equidistant along a corresponding electrode finger from the first busbar; and
the fourth plurality of electrode fingers each further comprise a first weighted section, wherein each first weighted section of the fourth plurality of electrode fingers is approximately equidistant along the corresponding electrode finger from the second busbar.

9. The electroacoustic resonator of claim 8 , wherein:
the first plurality of gap reflectors does not extend into an area between each first weighted section of the third plurality of electrode fingers and the first busbar; and
the second plurality of gap reflectors does not extend into an area between each first weighted section of the fourth plurality of electrode fingers and the second busbar.

10. The electroacoustic resonator of claim 1 , wherein the first plurality of gap reflectors comprises gap reflectors having different lengths.

11. The electroacoustic resonator of claim 10 , wherein the different lengths of the first plurality of gap reflectors is defined by the curve associated with the second wave shape.

12. The electroacoustic resonator of claim 1 , wherein the curve associated with the first wave shape and the curve associated with the second wave shape each comprises at least one of a cosine curve or a sine curve; and
wherein the curve associated with the first wave shape is offset from the curve associated with the second wave shape to provide a difference in overlapping finger length.

13. The electroacoustic resonator of claim 12 , wherein a period of the curve associated with the first wave shape and a period of the curve associated with the second wave shape each include a number of electrode fingers from 10 to 50.

14. The electroacoustic resonator of claim 1 , further comprising:
a first weighted section defined by a dielectric layer or first trimmed segments proximate to the first end of each of the first plurality of electrode fingers; and
a second weighted section defined by the dielectric layer or second trimmed segments proximate to the first end of each of the second plurality

Assignees

• Rf360 Singapore Pte Ltd

Inventors

• Chauhan Vikrant
• Mayer Markus
• Ammann Stefan
• Sabbagh Manuel

Classifications

• H03H9/64

  using surface acoustic waves · CPC title

• H03H9/25

  Constructional features of resonators using surface acoustic waves {(devices for manipulating acoustic surface waves in general G10K11/36)} · CPC title

• H03H3/08

  for the manufacture of resonators or networks using surface acoustic waves · CPC title

• H03H9/02881

  of diffraction of wave beam · CPC title

• H03H9/02858

  of wave front distortion · CPC title