Surface acoustic wave resonator device and manufacturing method thereof

A surface acoustic wave resonator device, having an interdigital electrode region comprising a first peripheral region, a first end region, a central region, a second end region and a second peripheral region sequentially arranged in a first direction, and the surface acoustic wave resonator device comprising:

• a piezoelectric substrate;
• an interdigital transducer, disposed on the piezoelectric substrate and comprising a plurality of interdigital electrodes which are located in the interdigital electrode region and comprise a first interdigital electrode and a second interdigital electrode;
• wherein the first interdigital electrode and the second interdigital electrode extend along the first direction and are alternately arranged along a second direction intersecting the first direction;
• the first interdigital electrode extends from the first peripheral region to the second end region, and the second interdigital electrode extends from the second peripheral region to the first end region;
• an intermediate layer, disposed on the piezoelectric substrate and covering the interdigital transducer;
• an acoustic velocity adjusting layer, disposed on a side of at least a portion of the intermediate layer away from the piezoelectric substrate, overlapped with the central region in a direction perpendicular to a main surface of the piezoelectric substrate, and configured to change an acoustic velocity in the central region;
• a passivation layer, disposed on a side of the intermediate layer away from the piezoelectric substrate;
• and
• a first protruding structure, disposed in the first end region and the second end region, and configured to change an acoustic velocity in the first end region and an acoustic velocity in the second end region,
• wherein the first protruding structure is disposed in a same layer as the interdigital transducer, and comprises end parts of the plurality of interdigital electrodes located in the first end region and the second end region;
• the end parts of the plurality of interdigital electrodes each have a second width in the second direction, and portions of the plurality of interdigital electrodes located in the central region each have a first width in the second direction, wherein the second width is greater than the first width.