Surface acoustic wave resonator, filter, and communication device

A surface acoustic wave resonator, comprising:

• a piezoelectric material layer, comprising a first region and two second regions arranged in a first direction;
• an interdigital transducer, located at a side of the piezoelectric material layer;
• and
• a reflective electrode structure, arranged in the same layer as the interdigital transducer,
• wherein the first region is located between the two second regions, the interdigital transducer is located in the first region, and the reflective electrode structure is located in the second regions,
• the surface acoustic wave resonator further comprises a groove located in the piezoelectric material layer, the groove is located in the second regions and at a side of the reflective electrode structure away from the interdigital transducer in the first direction,
• the reflective electrode structure comprises a plurality of reflective strip-shaped electrode portions, and the plurality of reflective strip-shaped electrode portions are arranged along the first direction, the groove is located at a side of the plurality of reflective strip-shaped electrode portions and intervals among the plurality of reflective strip-shaped electrode portions away from the interdigital transducer in the first direction, and
• wherein a size of the reflective electrode structure in the first direction ranges from 8 microns to 12 microns.

A surface acoustic wave resonator, comprising:

• a piezoelectric material layer, comprising a first region and two second regions arranged in a first direction;
• an interdigital transducer, located at a side of the piezoelectric material layer;
• and
• a reflective electrode structure, arranged in the same layer as the interdigital transducer,
• wherein the first region is located between the two second regions, the interdigital transducer is located in the first region, and the reflective electrode structure is located in the second regions,
• the surface acoustic wave resonator further comprises a groove located in the piezoelectric material layer, the groove is located in the second regions and at a side of the reflective electrode structure away from the interdigital transducer in the first direction,
• the reflective electrode structure comprises a plurality of reflective strip-shaped electrode portions, and the plurality of reflective strip-shaped electrode portions are arranged along the first direction, the groove is located at a side of the plurality of reflective strip-shaped electrode portions and intervals among the plurality of reflective strip-shaped electrode portions away from the interdigital transducer in the first direction,
• a size of the groove in the first direction is larger than a size of an interval between two adjacent ones of the plurality of reflective strip-shaped electrode portions in the first direction, and
• wherein the number of the plurality of reflective strip-shaped electrode portions comprised in the reflective electrode structure in each of the second regions ranges from 14 to 16.