An acoustic wave resonator includes a substrate; a resonating part disposed on a first surface of the substrate and including a first electrode, a piezoelectric layer, and a second electrode; and a cap disposed on the first surface of the substrate and including an accommodating part accommodating the resonating part. The resonating part is configured to be operated by either one or both of a signal output from a first device substrate disposed facing a second surface of the substrate on an opposite side of the substrate from the first surface of the substrate and a signal output from a second device substrate disposed on the cap.

An electronic component includes a first substrate having a substantially quadrangular planar shape and having a first surface and a second surface, the first surface and the second surface being opposite to each other, an element disposed on the first surface, four first terminals located adjacent to four corners on the second surface, respectively, and a second terminal located between the first terminals at respective ends of each of two sides opposite to each other of the second surface, an area of the second terminal being smaller than an area of each of the first terminals at the respective ends of each of the two sides, a width of the second terminal in an extension direction of each of the two sides being equal to or less than a width of each of the first terminals at the respective ends of each of the two sides in the extension direction.

Bulk acoustic wave resonators of two or more different filters can be on a common die. The two filters can be included in a multiplexer, such as a duplexer, or implemented as standalone filters. With bulk acoustic wave resonators of two or more filters on the same die, the filters can be implemented in less physical space compared to implementing the same filters of different die. Related methods, radio frequency systems, radio frequency modules, and wireless communication devices are also disclosed.

An RF diplexer circuit device using modified lattice, lattice, and ladder circuit topologies. The diplexer can include a pair of filter circuits, each with a plurality of series resonator devices and shunt resonator devices. In the ladder topology, the series resonator devices are connected in series while shunt resonator devices are coupled in parallel to the nodes between the resonator devices. In the lattice topology, a top and a bottom serial configurations each includes a plurality of series resonator devices, and a pair of shunt resonators is cross-coupled between each pair of a top serial configuration resonator and a bottom serial configuration resonator. The modified lattice topology adds baluns or inductor devices between top and bottom nodes of the top and bottom serial configurations of the lattice configuration. A multiplexing device or inductor device can be configured to select between the signals coming through the first and second filter circuits.

Embodiments of this application provide a filter and a method for adjusting performance of a filter, so as to quickly adjust performance of a filter. The filter includes at least two acoustic wave resonators; and a performance adjustment structure, connected to an output end of a first acoustic wave resonator and an input end of a second acoustic wave resonator, where the first acoustic wave resonator and the second acoustic wave resonator are any two of the at least two acoustic wave resonators, the performance adjustment structure includes a capacitor structure and/or an inductor structure, and the performance adjustment structure is configured to adjust an energy coupling mode between the first acoustic wave resonator and the second acoustic wave resonator.

Wireless communication circuitry is disclosed. The wireless communication circuitry includes an antenna terminal and an electrically conductive path between a first port terminal and the antenna terminal through a second port terminal. Also included is a bulk acoustic wave filter configured to filter and pass a desired radio frequency signal between the first port terminal and the second port terminal. Further included is a first magnetic coupling component that is electrically connected to the electrically conductive path and a resonant circuit made up of a capacitor and a second magnetic coupling component that is magnetically coupled to the first magnetic coupling component. The resonant circuit is tuned to suppress an undesired desired radio frequency signal that in some embodiments is the second harmonic of the desired radio frequency signal.

A radio frequency (RF) front-end (RFFE) device includes a die having a front-side dielectric layer on an active device. The active device is on a first substrate. The RFFE device also includes a microelectromechanical system (MEMS) device. The MEMS device is integrated on the die at a different layer than the active device. The MEMS device includes a cap layer composed of a cavity in the front-side dielectric layer of the die. The cavity in the front-side dielectric layer is between the first substrate and a second substrate. The cap is coupled to the front-side dielectric layer.

An acoustic wave device includes: a first substrate that includes a first acoustic wave filter located on an upper surface of the first substrate; a second substrate that is flip-chip mounted on the upper surface of the first substrate through a bump, and includes a second acoustic wave filter on a lower surface of the second substrate, the lower surface of the second substrate facing the upper surface of the first substrate across an air gap; and a shield electrode that is supported by the upper surface of the first substrate, and is located between at least a part of the first acoustic wave filter and at least a part of the second acoustic wave filter through the air gap.

An electronic device includes: a first substrate including a first functional element located on an upper surface of the first substrate; a second substrate that is flip-chip mounted on the upper surface of the first substrate through a bump, and includes a second functional element located on a lower surface of the second substrate; and a sealing member that is located on the upper surface of the first substrate, surrounds the second substrate in plan view, is not located between the first substrate and the second substrate, seals the first functional element and the second functional element so that the first functional element and the second functional element are located across an air gap.

The present invention relates to a filter chip (1), comprising an interconnection of at least one first and one second resonator (2, 3) operating with bulk acoustic waves, wherein the first resonator (2) operating with bulk acoustic waves comprises a first piezoelectric layer (4) that is structured in such a way that the first resonator (2) has a lower resonant frequency than the second resonator (3).