H03H9/586

TRANSVERSELY-EXCITED FILM BULK ACOUSTIC RESONATOR PACKAGE
20250055441 · 2025-02-13 ·

A radio frequency filter includes bulk acoustic resonator chips that each include a substrate; a piezoelectric plate that includes multiple separate plates; and a conductor pattern on the piezoelectric layer and including an interdigitated transducer (IDT) with interleaved fingers on the piezoelectric layer opposite the substrate. The filter further includes an interposer having a surface facing the piezoelectric layer of each of the plurality of bulk acoustic resonator chips; a conductor pattern on the surface of the interposer; a conductive metal bump between the piezoelectric layer and the interposer that electrically connects the plurality of bulk acoustic resonator chips to the interposer; and a cover bonded to the substrates of the plurality of bulk acoustic resonator chips and to the interposer, wherein the cover seals an interior of the plurality bulk acoustic resonator chips.

Stacked filter package having multiple types of acoustic wave devices

A stacked filter package is disclosed. The stacked filter package can include a first acoustic wave device having a first device type. The first acoustic wave device includes a first substrate having a first coefficient of thermal expansion. The stacked filter package can include a second acoustic wave device having a second device type different from the first device type. The second acoustic wave device includes a second substrate having a second coefficient of thermal expansion. The second coefficient of thermal expansion is at least double the first coefficient of thermal expansion. The stacked filter package can include a bonding structure between the first and second substrates. The bonding structure couples the first and second substrate.