An SAW device includes a piezoelectric substrate, an IDT electrode on a first major surface of the piezoelectric substrate, a capacitance element which is located on the first major surface and is connected to the IDT electrode, and a cover which is superimposed only on the capacitance element between the IDT electrode and the capacitance element.

A composite electronic component includes a first acoustic wave filter, a second acoustic wave filter, a spacer layer, and a switch. The second acoustic wave filter faces the first acoustic wave filter in a first direction. The switch switches an ON state and an OFF state of the first acoustic wave filter and an ON state and an OFF state of the second acoustic wave filter. A first functional electrode and a second functional electrode are located in a hollow space and face each other in the first direction. The switch brings at least one of the first acoustic wave filter and the second acoustic wave filter into the OFF state.

A wideband filter includes a passive substrate and an acoustic resonator chip on the passive substrate. The wideband filter further includes a pair of 3D inductors and a 3D transformer on the passive substrate. The pair of 3D inductors and the 3D transformer are connected to the acoustic resonator chip.

Embodiments of the invention include an acoustic wave resonator (AWR) module. In an embodiment, the AWR module may include a first AWR substrate and a second AWR substrate affixed to the first AWR substrate. In an embodiment, the first AWR substrate and the second AWR substrate define a hermetically sealed cavity. A first AWR device may be positioned in the cavity and formed on the first AWR substrate, and a second AWR device may be positioned in the cavity and formed on the second AWR substrate. In an embodiment, a center frequency of the first AWR device is different than a center frequency of the second AWR device. In additional embodiment of the invention, the AWR module may be integrated into a hybrid filter. The hybrid filter may include an AWR module and other RF passive devices embedded in a packaging substrate.

A filter device includes a first filter chip including a first signal terminal and a second filter chip including a second signal terminal that are mounted above a package substrate including a substrate main body. First and second signal electrode pads are provided on a first main surface of the package substrate and are respectively joined to the first and second signal terminals. First and second outer terminals are provided on a second main surface of the substrate main body. The first and second signal electrode pads and the first and second outer terminals are connected to each other with first and second wirings, respectively. The second outer terminal is located at the first signal electrode pad side and the first outer terminal is located at the second signal electrode pad side when seen from above.

An electronic device package includes a lower surface for conducting electronic signals, a first solder bond pad having a first size disposed on the lower surface, and a plurality of second solder bond pads having second sizes smaller than the first size disposed on the lower surface and surrounding the first solder bond pad.

A surface acoustic wave device includes a piezoelectric substrate, an interdigital transducer (IDT) electrode on the substrate, a cover over the substrate and IDT electrode, and hollow spaces between the IDT electrode and the cover. The hollow spaces are defined by partition supports between the substrate and the cover. The partition supports include a first and second partition supports extending in a first direction without contacting each other. The first and second partition supports each include first and second ends along the first direction. The first and second direction perpendicular to the first direction. The first end of the first partition support is closer to an outer periphery of the substrate than is the second end, and the first end of the second partition support is farther away from the outer periphery than is the second end.

An elastic wave device includes a support substrate, a film stack including a piezoelectric thin film, and an IDT electrode. The film stack is partially absent in a region outside a region where the IDT electrode is located in plan view. The elastic wave device further includes a support layer located on the support substrate in at least a portion of a region where the film stack is partially absent and surrounds a region where the film stack is located in plan view and a cover member located on the support layer. The cover member defines a hollow space facing the IDT electrode together with the piezoelectric thin film and the support layer.

An elastic wave device includes a mount board, a transmit filter, a receive filter, and a sealing resin layer. The transmit filter includes a first piezoelectric substrate, and is joined to the mount board by first bumps. The receive filter includes a second piezoelectric substrate, and is joined to the mount board by second bumps. The sealing resin layer is provided on the mount board. The height of each first bump is H1; the joint area, on the first piezoelectric substrate side, of each first bump is A1; and the joint area, on the mount board side, of each first bump is B1; the height of each second bump is H2; the joint area, on the second piezoelectric substrate side, of each second bump is A2; and the joint area, on the mount board side, of each second bump is B2. The first bumps and the second bumps satisfy at least one of: A1>A2 and B1>B2; and H1<H2.

A method of fabricating an electronics package includes forming a cavity in a first surface of a semiconductor substrate, forming one or more passive devices on the semiconductor substrate, forming a microelectromechanical device on a piezoelectric substrate, and bonding the semiconductor substrate to the piezoelectric substrate with the microelectromechanical device disposed within the cavity.