Patent ID: 11967943
Assignee: MURATA MANUFACTURING CO., LTD.
Field: Basic communication processes (Electrical engineering)
Classification: CPC H  Y | IPC H

Claim 11:
12. A filter device, comprising:
a substrate having a front surface;
at least one piezoelectric plate supported by the front surface of the substrate;
a plurality of interdigital transducers (IDTs) of a respective plurality of acoustic resonators including a shunt resonator and a series resonator, interleaved fingers of each of the plurality of IDTs at a respective diaphragm of one or more diaphragms of the at least one piezoelectric plate spanning respective cavities; and
an etch-stop layer on a surface of the at least one piezoelectric plate between interleaved fingers of the plurality of IDTs,
wherein the etch-stop layer is impervious to an etch process capable of forming the interleaved fingers.