A radio-frequency module (20) includes a module substrate (50) and a filter (21). The filter (21) has a sensitive GND electrode and a non-sensitive GND electrode that are connected to an external-connection ground terminal of the module substrate (50), and parallel-arm resonators. An inductance component generated by the sensitive GND electrode shifts, by a first shift amount, an attenuation pole that corresponds to a parallel-arm resonator and that is formed near a pass band. An inductance component generated by the non-sensitive GND electrode shifts, by a second shift amount, an attenuation pole that corresponds to a parallel-arm resonator and that is formed near the pass band. The first shift amount is larger than the second shift amount, and the distance between the sensitive GND electrode and the external-connection ground terminal is smaller than the distance between the non-sensitive GND electrode and the external-connection ground terminal.

A method of fabricating a bonded wafer with low carrier lifetime in silicon comprises providing a silicon substrate having opposing top and bottom surfaces, modifying a top portion of the silicon substrate to reduce carrier lifetime in the top portion relative to the carrier lifetime in portions of the silicon substrate other than the top portion, bonding a piezoelectric layer having opposing top and bottom surfaces separated by a distance T over the top surface of the silicon substrate, and providing a pair of electrodes having fingers that are inter-digitally dispersed on a top surface of the piezoelectric layer, the electrodes comprising a portion of a Surface Acoustic Wave (SAW) device. The modifying and bonding steps may be performed in any order. The modified top portion of the silicon substrate prevents the creation of a parasitic conductance within that portion during operation of the SAW device.

A surface acoustic wave device is disclosed. The surface acoustic wave device can include a multilayer piezoelectric substrate having a support substrate and a piezoelectric layer over the support substrate. The piezoelectric layer has a first surface facing the support substrate and a second surface opposite the first surface. The surface acoustic wave device can include an interdigital transducer electrode having a first portion and a second portion. The first portion is positioned below the second surface of the piezoelectric layer and the second portion is positioned above the second surface. The first portion has a first sidewall and a second portion has a second sidewall angled relative to the first sidewall.

An improved DMS filter with electrode structures between a first port and a second port is provided. Wiring junctions are realized in multilayer crossing with dielectric material in between. There are insulating patches (L2) between crossing conductor layers (L1,L3). Signal wirings may be realized with multiple conductor layers (L1, L3) to reduce wiring resistance and the upper conductor layer (L3) of the signal wiring may partly overlap the insulating patches (L2). The insulating patches (L2) may extend over the acoustic path to achieve temperature compensation.

An electronic component includes first and second element substrates, first and second functional element portions, and a support layer that defines a first hollow space over a first functional electrode with the first and second element substrates. A second functional electrode is located on a first main surface of the second element substrate. The electronic component further includes a first conductive layer that is provided on a second main surface of the second element substrate and that is connected to ground potential. The first conductive layer opposes the first functional electrode in the first hollow space. The first conductive layer is overlapped with at least a portion of the first and second functional electrodes in a plan view.

An acoustic wave device includes: a substrate; an acoustic wave resonator that is formed on the substrate; a first wiring line that is formed on the substrate and is electrically coupled to the acoustic wave resonator; and a second wiring line that is electrically coupled to the first wiring line, at least a part of the second wiring line being formed immediately above the acoustic wave resonator across an air gap.

A composite filter device includes a common terminal disposed on an element substrate including a piezoelectric layer, first and second band pass filters disposed on the element substrate, and connected at one end thereof to the common terminal, a shield electrode interposed between a signal line and the first band pass filter, the signal line being disposed on the element substrate and connecting the common terminal to the first and second band pass filters, and an inductor connected between the shield electrode and a reference potential line.

An acoustic wave device according to the present invention includes a piezoelectric substrate including a piezoelectric layer, a functional electrode provided on the piezoelectric layer, a first support layer provided on the piezoelectric substrate so as to surround the functional electrode, a covering portion provided on or above the first support layer and including a first main surface positioned on the functional electrode side and a second main surface opposite to the first main surface, a silicon oxide layer provided on the first main surface side of the covering portion, and an inductor provided on the silicon oxide layer and made of a wire. The covering portion is made of silicon. The acoustic wave device further includes one of an amorphous silicon layer and a polysilicon layer provided between the covering portion and the silicon oxide layer.

An acoustic wave device includes: a substrate; a first acoustic wave resonator and a second acoustic wave resonator located on the substrate; a first wiring line electrically coupled to the first acoustic wave resonator, located on the substrate, and located between the first acoustic wave resonator and the second acoustic wave resonator; and a second wiring line electrically coupled to the second acoustic wave resonator, located on the substrate, located between the first acoustic wave resonator and the second acoustic wave resonator, having an electric potential different from an electric potential of the first wiring line, and having a thickness greater than a thickness of the first wiring line.

A surface acoustic wave device is disclosed. The surface acoustic wave device can include a support substrate structure, a first piezoelectric layer over the support substrate structure, a second piezoelectric layer over the first piezoelectric layer, a first acoustic wave element in electrical communication with the first piezoelectric layer, and a second acoustic wave element in electrical communication with the second piezoelectric layer.