Embodiments of this disclosure relate to reducing coupling between acoustic wave resonators. An isolation region of a substrate can be located between acoustic wave resonators. The isolation region can reduce capacitive coupling through the substrate between the acoustic wave resonators. In certain embodiments, the isolation region can be located between acoustic wave resonators of different filters to thereby increase isolation between the filters.

An acoustic wave device includes a substrate, a transmission filter formed on the substrate, a reception filter formed on the substrate, a transmission ground pad of the transmission filter, the transmission ground pad is formed on the substrate, and a reception ground pad of the reception filter, the reception ground pad is formed on the substrate. The transmission filter includes a plurality of series resonators and a plurality of parallel resonators. The plurality of parallel resonators includes a first parallel resonator electrically connected to the reception ground pad.

To provide a radio-frequency module and a communication apparatus capable of achieving more excellent impedance characteristics. A radio-frequency module includes a first acoustic-wave filter (a first reception filter), a second acoustic-wave filter (a second reception filter), a switch (an antenna switch), a first inductor, and a second inductor. The first acoustic-wave filter transmits a signal in a first communication band. The second acoustic-wave filter transmits a signal in a second communication band. The first inductor is provided between ground and a node on a signal path (a second reception path) with which the switch is connected to the second acoustic-wave filter. The second inductor is connected in series between the switch and the first inductor on the signal path.

A filter device having a reduced sensitivity to production tolerances comprises a multilayer panel with integrated wiring, a piezoelectric substrate mounted to the panel. A first filter circuit (FC.sub.1) and a signal path (SP) comprising a second filter circuit are realized on the substrate and connected to a common antenna terminal (AT) as well as to a common node (CN) located on top of the piezoelectric substrate. A first matching circuit (MC.sub.1) and further matching circuits (MC.sub.2) are realized by the wiring in the multilayer panel.

A bulk acoustic wave resonator is disclosed. The bulk acoustic wave resonator can include a ceramic substrate, and a piezoelectric layer on the ceramic substrate. The bulk acoustic wave resonator can also include first and second electrodes positioned on opposing sides of the piezoelectric layer. The bulk acoustic wave resonator can also include passivation layers that includes a first passivation layer and a second passivation layer. The first passivation layer can be positioned between the ceramic substrate and the first electrode. The second electrode can be positioned between the piezoelectric layer and the second passivation layer. The bulk acoustic wave resonator can further include a frame structure along an edge of an active region of the bulk acoustic wave resonator.

Aspects of this disclosure relate to a method of manufacturing a packaged acoustic wave component with two acoustic wave devices interconnected by a thermally conductive frame. The method includes providing a first acoustic wave device having a multi-layer piezoelectric substrate structure with a first piezoelectric layer disposed over a first support layer and an interdigital transducer electrode. The method further includes stacking the first acoustic wave device relative to a second acoustic wave device such that a thermally conductive frame extends between the first acoustic wave device and the second acoustic wave device. The thermally conductive frame provides a thermal path for heat dissipation from the first acoustic wave device to the second acoustic wave device.

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.

A multiplexer includes: a first terminal; a second terminal; a third terminal; a first filter connected between the first and second terminals, including a first capacitor, a first inductor, and one or more first acoustic wave resonators, and having a first passband; a second filter connected between the first and third terminals, including a second capacitor, a second inductor, and one or more second acoustic wave resonators, and having a second passband higher than the first passband; a substrate having a surface on which at least one first acoustic wave resonator of the one or more first acoustic wave resonators and at least one second acoustic wave resonator of the one or more second acoustic wave resonators are located; and a metal structure located on the surface and located between the at least one first acoustic wave resonator and the at least one second acoustic wave resonator.

A substrate that includes an encapsulation layer, a first acoustic resonator, a second acoustic resonator, at least one first dielectric layer, a plurality of first interconnects, at least one second dielectric layer, and a plurality of second interconnects. The first acoustic resonator is located in the encapsulation layer. The first acoustic resonator includes a first piezoelectric substrate comprising a first thickness. The second acoustic is located in the encapsulation layer. The second acoustic resonator includes a second piezoelectric substrate comprising a second thickness that is different than the first thickness. The at least one first dielectric layer is coupled to a first surface of the encapsulation layer. The plurality of first interconnects is coupled to the first surface of the encapsulation layer. The plurality of first interconnects is located at least in the at least one first dielectric layer.

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.