LADDER FILTER WITH TRANSVERSELY-EXCITED FILM BULK ACOUSTIC RESONATORS HAVING DIFFERENT PITCHES: abstract simplified (18194012)

• This abstract for appeared for patent application number 18194012 Titled 'LADDER FILTER WITH TRANSVERSELY-EXCITED FILM BULK ACOUSTIC RESONATORS HAVING DIFFERENT PITCHES'

Simplified Explanation

The abstract describes a filter device that uses a substrate and a piezoelectric plate. The device includes multiple resonators, each with interdigital transducers (IDTs) that have interleaved fingers. These IDTs are placed over cavities on the piezoelectric plate. The resonators have different pitches for their interleaved fingers, which helps adjust their resonance frequencies. Additionally, a dielectric layer is applied to the surface of the piezoelectric plate.

Original Abstract Submitted

A filter device is provided that includes a substrate having a surface and a piezoelectric plate supported by the substrate. A plurality of interdigital transducers (IDTs) for multiple resonators are provided that each have interleaved fingers at respective diaphragms of the piezoelectric plate disposed over one or more cavities. Moreover, a first resonator includes a first plurality of interleaved fingers having a first pitch and a second resonator includes a second plurality of interleaved fingers having a second pitch that is different than the first pitch. This configuration adjusts the resonance frequencies of each resonator. Moreover, a dielectric layer may be uniformly disposed over at least one surface of the respective diaphragms of the piezoelectric plate.