Patent ID: 11894835
Assignee: MURATA MANUFACTURING CO., LTD.
Field: Basic communication processes (Electrical engineering)
Classification: CPC H | IPC H

Claim 9:
10. An acoustic resonator comprising:
a back surface of a first piezoelectric plate bonded to a top surface of a substrate comprised of a plurality of layers and having at least a first cavity;
a planarized top surface of the first piezoelectric plate forming a first thickness of the first piezoelectric plate with the back surface of the first piezoelectric plate;
the first piezoelectric plate spanning the first cavity;
a first interdigital transducer (IDT) on a front surface of the first piezoelectric plate that is opposite the substrate and having interleaved fingers over the first cavity;
a first dielectric layer on a top surface of the first piezoelectric plate and covering the first IDT;
a back surface of a second piezoelectric plate bonded to a top surface of the first dielectric layer that is opposite the first piezoelectric plate; and
a second dielectric layer coupled to a top surface of the second piezoelectric plate that is opposite the back surface without any electrodes therebetween,
wherein the second piezoelectric plate spans the first cavity.