Bulk acoustic wave resonator and manufacturing method thereof and filter

A bulk acoustic wave resonator, comprising:

• a resonant body structure, comprising a piezoelectric layer, a first electrode structure layer and a second electrode layer, wherein the piezoelectric layer has a first side and a second side opposite to each other in a first direction;
• the first electrode structure layer is disposed on the first side of the piezoelectric layer and comprises a first electrode structure;
• the second electrode layer is disposed on the second side of the piezoelectric layer and comprises a second electrode;
• a carrier structure, disposed on a side of the resonant body structure away from the second electrode layer, wherein a first cavity is arranged between the carrier structure and the resonant body structure, and a portion of the first electrode structure is exposed to the first cavity;
• and
• a cover structure, disposed on a side of the resonant body structure opposite to the carrier structure, and comprising a cover bonding layer and a cover substrate, wherein the cover bonding layer is disposed between the cover substrate and the resonant body structure in the first direction, a second cavity is provided between the cover structure and the resonant body structure, and a portion of the second electrode layer is exposed to the second cavity;
• wherein the carrier structure comprises:
• a supporting dielectric layer, disposed on a side of the first electrode structure layer away from the piezoelectric layer;
• a cavity boundary layer, located on a side of the supporting dielectric layer and the resonant body structure away from the cover structure, and defining a portion of a boundary of the first cavity,
• a carrier bonding layer, located on a side of the cavity boundary layer away from the resonant body structure, and
• a carrier substrate, located on a side of the carrier bonding layer away from the resonant body structure.