Resonant Inc.
LOW LOSS TRANSVERSELY-EXCITED FILM BULK ACOUSTIC RESONATORS AND FILTERS

Abstract:

An acoustic resonator device includes a diaphragm including a portion of the piezoelectric plate spanning a cavity in a substrate. A conductor pattern on a surface of the piezoelectric plate includes an interdigital transducer (IDT) with a first busbar, a second busbar, and a plurality of interleaved fingers, wherein the plurality of interleaved fingers extend alternately from the first and second busbars, overlapping portions of the plurality of interleaved fingers on the diaphragm. The conductor pattern also includes first and second reflector elements on the diaphragm proximate and parallel to a first finger of the plurality of interleaved fingers, and third and fourth reflector element on the diaphragm proximate and parallel to a last finger of the plurality of interleaved fingers.