CN-224233668-U - Surface acoustic wave resonator and electronic device

CN224233668UCN 224233668 UCN224233668 UCN 224233668UCN-224233668-U

Abstract

The utility model discloses a surface acoustic wave resonator and an electronic device, which are applied to the technical field of surface acoustic waves, wherein the bottom of a first electrode finger is connected with a first bus bar through a connecting part, and the top of a second electrode finger is mutually separated from the first bus bar; the first bus bar is provided with an extension part towards the top of the second electrode finger, the top of the extension part is mutually separated from the top of the corresponding second electrode finger, the top edge of the extension part is provided with a first protruding part extending along the length direction, an inner layer edge sound velocity zone is formed based on the first protruding part, an inner layer sound velocity zone is formed between the first bus bar and the inner layer edge sound velocity zone based on the extension part, and the sound velocity of the inner layer edge sound velocity zone is smaller than that of the inner layer edge sound velocity zone. The first protruding parts are arranged at the tops of the extending parts, the inner-layer edge sound velocity area is formed based on the first protruding parts, and the sawtooth structures formed by the plurality of first protruding parts can enable sound waves to diffuse and reflect in the transverse direction, so that the generation of transverse modes is effectively restrained.

Inventors

PENG BOHUA
ZHU MINGGUO
LI PING
HU NIANCHU
JIA BIN

Assignees

开元通信技术（厦门）有限公司

Dates

Publication Date: 20260512
Application Date: 20250613

Claims (10)

1. A surface acoustic wave resonator, comprising: a piezoelectric substrate; an interdigital transducer arranged on the surface of the piezoelectric substrate; The interdigital transducer comprises a first bus bar and a second bus bar which are oppositely arranged, and the first bus bar and the second bus bar are parallel to the length direction; a first electrode finger and a second electrode finger are arranged between the first bus bar and the second bus bar, the bottom of the first electrode finger is connected with the first bus bar through a connecting part, and the top of the second electrode finger is mutually separated from the first bus bar; The first bus bar is provided with an extension part towards the top of the second electrode finger, the top of the extension part is mutually separated from the corresponding top of the second electrode finger, the top edge of the extension part is provided with a first protruding part extending along the length direction, an inner layer edge sound velocity zone is formed based on the first protruding part, an inner layer sound velocity zone is formed between the first bus bar and the inner layer edge sound velocity zone based on the extension part, and the sound velocity of the inner layer edge sound velocity zone is smaller than that of the inner layer edge sound velocity zone.
2. The surface acoustic wave resonator according to claim 1, characterized in that the top edge of the extension is provided with the first protruding portion along both sides in the length direction.
3. The surface acoustic wave resonator according to claim 1, characterized in that the connecting portion is provided with the first protruding portion corresponding to a position edge of the top portion of the extension portion.
4. A surface acoustic wave resonator according to claim 3, wherein the first protruding portion is provided at both side edges of the connecting portion corresponding to the position of the top of the extending portion.
5. The surface acoustic wave resonator according to claim 1, characterized in that in the length direction, the width of the extension portion, the width of the connection portion, the width of the first electrode finger, and the width of the second electrode finger are all the same; And/or the extension part, the connection part, the first electrode finger and the second electrode finger are parallel to each other.
6. The surface acoustic wave resonator according to claim 1, characterized in that a gap is provided between the top of the extension and the top of the corresponding second electrode finger, a transition sound velocity zone is formed based on the gap, and the sound velocity of the inner layer sound velocity zone is smaller than the sound velocity of the transition sound velocity zone.
7. The surface acoustic wave resonator according to claim 1, characterized in that an outer acoustic velocity zone is formed based on the first bus bar, the acoustic velocity of the outer acoustic velocity zone being greater than the acoustic velocity of the inner acoustic velocity zone.
8. The surface acoustic wave resonator according to claim 1, characterized in that a top edge of the second electrode finger is provided with a second protrusion extending in the longitudinal direction, a central edge sound velocity zone is formed based on the second protrusion, and a central sound velocity zone is formed based on the first electrode finger and the second electrode finger, the sound velocity of the central edge sound velocity zone being smaller than the sound velocity of the central sound velocity zone.
9. The surface acoustic wave resonator according to claim 8, characterized in that the bottom edge of the first electrode finger is provided with the second protrusion.
10. An electronic device comprising the surface acoustic wave resonator according to any one of claims 1 to 9.

Description

Surface acoustic wave resonator and electronic device Technical Field The present utility model relates to the field of surface acoustic wave technology, and in particular, to a surface acoustic wave resonator and an electronic device. Background The surface acoustic wave (Surface Acoustic Wave, SAW) device is a solid device that propagates on the surface of a piezoelectric material by using the surface acoustic wave, and has been widely used in the field of wireless communication because of its excellent performance, low cost, simple process flow, and the like. The conventional surface acoustic wave filter generates a transverse mode in the acoustic wave propagation process, and the Q value of the surface acoustic wave device is reduced by the transverse mode, so how to effectively inhibit the transverse mode generated in the acoustic wave propagation process by the surface acoustic wave device is a problem which needs to be solved by those skilled in the art. Disclosure of utility model The utility model aims to provide a surface acoustic wave resonator capable of effectively inhibiting the generation of a transverse mode, and another aim of the utility model is to provide an electronic device capable of effectively inhibiting the generation of the transverse mode. In order to solve the above technical problems, the present utility model provides a surface acoustic wave resonator, including: a piezoelectric substrate; an interdigital transducer arranged on the surface of the piezoelectric substrate; The interdigital transducer comprises a first bus bar and a second bus bar which are oppositely arranged, and the first bus bar and the second bus bar are parallel to the length direction; a first electrode finger and a second electrode finger are arranged between the first bus bar and the second bus bar, the bottom of the first electrode finger is connected with the first bus bar through a connecting part, and the top of the second electrode finger is mutually separated from the first bus bar; The first bus bar is provided with an extension part towards the top of the second electrode finger, the top of the extension part is mutually separated from the corresponding top of the second electrode finger, the top edge of the extension part is provided with a first protruding part extending along the length direction, an inner layer edge sound velocity zone is formed based on the first protruding part, an inner layer sound velocity zone is formed between the first bus bar and the inner layer edge sound velocity zone based on the extension part, and the sound velocity of the inner layer edge sound velocity zone is smaller than that of the inner layer edge sound velocity zone. Optionally, the top edge of the extension portion is provided with the first protruding portion along both sides of the length direction. Optionally, the connecting portion is provided with the first protruding portion corresponding to a position edge of the top of the extending portion. Optionally, the first protruding portion is disposed at two side edges of the connecting portion corresponding to the top of the extending portion. Optionally, in the length direction, the width of the extension portion, the width of the connection portion, the width of the first electrode finger, and the width of the second electrode finger are all the same; And/or the extension part, the connection part, the first electrode finger and the second electrode finger are parallel to each other. Optionally, a gap is formed between the top of the extension portion and the top of the corresponding second electrode finger, a transition sound velocity zone is formed based on the gap, and the sound velocity of the inner layer sound velocity zone is smaller than the sound velocity of the transition sound velocity zone. Optionally, an outer layer sound velocity zone is formed based on the first bus bar, and the sound velocity of the outer layer sound velocity zone is greater than the sound velocity of the inner layer sound velocity zone. Optionally, a second protruding part extending along the length direction is arranged at the top edge of the second electrode finger, a central edge sound velocity zone is formed based on the second protruding part, and a central sound velocity zone is formed based on the first electrode finger and the second electrode finger, wherein the sound velocity of the central edge sound velocity zone is smaller than that of the central sound velocity zone. Optionally, the bottom edge of the first electrode finger is provided with the second protruding part. The utility model also provides an electronic device comprising a surface acoustic wave resonator as claimed in any one of the preceding claims. The surface acoustic wave resonator comprises a piezoelectric substrate, an interdigital transducer arranged on the surface of the piezoelectric substrate, wherein the interdigital transducer comprises a first bus bar and a second bus bar which are o