Patent ID: 11876498
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;
at least one piezoelectric layer attached directly to the substrate or by one or more intermediate material layers, the at least one piezoelectric layer comprising a plurality of diaphragms that are over a plurality of cavities, respectively, in at least one of the substrate and the one or more intermediate material layers, wherein:
a first portion of the at least one piezoelectric layer has a first thickness, and
a surface of a second portion of the at least one piezoelectric layer is recessed relative to a surface of the first portion of the at least one piezoelectric layer such that the second portion of the at least one piezoelectric layer has a second thickness less than the first thickness; and

a conductor pattern at the first and second portions of the at least one piezoelectric layer, the conductor pattern comprising:
a first interdigital transducer (IDT) with interleaved fingers on a diaphragm having the first thickness, and
a second IDT with interleaved fingers on a diaphragm having the second thickness.