Patent ID: 11888463
Assignee: MURATA MANUFACTURING CO., LTD.
Field: Basic communication processes (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A filter device, comprising:
a substrate having a surface;
a single-crystal piezoelectric plate having front and back surfaces, the back surface attached to the surface of the substrate, portions of the single-crystal piezoelectric plate forming a plurality of diaphragms spanning respective cavities in the substrate; and
a conductor pattern formed on the front surface, the conductor pattern defining a low band filter including one or more low band shunt resonators and one or more low band series resonators and a high band filter including one or more high band shunt resonators and one or more high band series resonators, wherein
interleaved fingers of interdigital transducers (IDTs) of the one or more low band shunt resonators are disposed on respective diaphragms having a first thickness ts1,
interleaved fingers of IDTs of the one or more high band series resonators are disposed on respective diaphragms having a second thickness ts2 less than ts1, and
interleaved fingers of IDTs of the one or more low band series resonators and the one or more high band shunt resonators are disposed on respective diaphragms having other thicknesses intermediate ts1 and ts2.