Murata Manufacturing Co., Ltd.

Akira Michigami

Katsuya Daimon

Taku Kikuchi

Koichiro Kawasaki

Toshimaro Yoneda

Yasumasa Taniguchi

Tsutomu Takai

Daisuke Sekiya

Yasuharu Nakai

Keiji Okada

Noriyoshi Ota

Masashi Tsubokawa

Takuma Kuzushita

An acoustic wave device includes a support substrate, a low-acoustic-velocity film on the support substrate, a piezoelectric layer on the low-acoustic-velocity film, an IDT electrode on the piezoelectric layer, and a high-acoustic-velocity film between the support substrate and the low-acoustic-velocity film. An acoustic velocity of a bulk wave propagating through the low-acoustic-velocity film is lower than an acoustic velocity of a bulk wave propagating through the piezoelectric layer. An acoustic velocity of a bulk wave propagating though the high-acoustic-velocity film is higher than an acoustic velocity of an acoustic wave propagating through the piezoelectric layer. Adhesion between the low-acoustic-velocity film and the support substrate is higher than adhesion between the high-acoustic-velocity film and the support substrate. The high-acoustic-velocity film is between portions of the support substrate and the low-acoustic-velocity film, and a portion of the low-acoustic-velocity film and a portion of the support substrate contact each other.

Acoustic wave device

A filter device includes first and second filters respectively having first and second passbands, the second passband being in a frequency range higher than the first passband. The first and second filters are commonly connected to a common terminal. In the first filter, multiple parallel arm resonators define a parallel connection unit in which the parallel arm resonators are connected in parallel with no serial arm resonators interposed therebetween. The parallel arm resonators in the parallel connection unit include first and second parallel arm resonators having anti-resonant frequencies different from each other. In combined impedance-frequency characteristics of the parallel arm resonators in the parallel connection unit, at least one anti-resonant frequency other than a highest anti-resonant frequency is equal to or higher than 2f−fand equal to or lower than 2f−f.

Filter device

An acoustic wave device includes a substrate, an interdigital transducer electrode including electrode fingers on a main surface of the substrate, and a protection film covering the main surface of the substrate, and side surfaces and upper surfaces of the electrode fingers. The protection film includes a portion covering the main surface of the substrate, an intermediate portion between two of the electrode fingers adjacent to each other, and a vicinity portion of the electrode fingers. The intermediate portion is thicker than the vicinity portion.

Acoustic wave device and multiplexer

An acoustic wave filter includes a series-arm resonator, a first parallel-arm resonator, and a second parallel-arm resonator. The series-arm resonator is disposed on a path connecting first and second input/output terminals. The first parallel-arm resonator is disposed on a path that connects ground with a node, which is located on a path connecting the series-arm resonator with the first input/output terminal. The second parallel-arm resonator is disposed on a path that connects ground with a node, which is located on a path connecting the series-arm resonator with the second input/output terminal. The parallel-arm resonator has a resonant frequency lower than the resonant frequency of the second parallel-arm resonator. The first parallel-arm resonator has an anti-resonant frequency higher than the anti-resonant frequency of the second parallel-arm resonator. The second parallel-arm resonator has the highest resonant frequency of all the parallel-arm resonators.

Acoustic wave filter device

An acoustic wave resonator includes an IDT electrode that is on or above a piezoelectric plate and includes a periodic withdrawal weighted portion in each of a plurality of regions for at least two or more periods in an acoustic wave propagation direction. A periodic withdrawal weighted portion in at least one of the regions is different from a periodic withdrawal weighted portion in at least one of the other regions.

Acoustic wave resonator and multiplexer

A surface acoustic wave element includes a substrate including a LiNbOpiezoelectric single crystal, a first dielectric layer provided on the substrate, and an IDT electrode provided on the first dielectric layer, and propagates a high-frequency signal on the substrate using a Rayleigh wave.

Surface acoustic wave element

An acoustic wave device includes a piezoelectric substrate including a piezoelectric layer made of lithium tantalate, an IDT electrode on the piezoelectric substrate, and a pair of reflectors on both sides of the IDT electrode on the piezoelectric substrate in an acoustic wave propagation direction. SH waves are used as a principal mode. The IDT electrode includes electrode fingers and the pair of reflectors each including electrode fingers. When a length along a direction orthogonal to a direction in which the electrode fingers extend is a width, each of the reflectors includes first and second electrode fingers having different widths. Four consecutive electrode fingers, which are any four of the electrode fingers of each of the reflectors, include both of the first and second electrode fingers and distances between centers of the four consecutive electrode fingers are equal or substantially equal.

Acoustic wave device, band pass filter, duplexer, and multiplexer

An elastic wave device includes a piezoelectric substrate, elastic wave resonators on or in the piezoelectric substrate, and a dielectric film disposed on the piezoelectric substrate and covering the elastic wave resonators. The elastic wave resonators includes respective IDT electrodes on the piezoelectric substrate. When a wavelength specified by an electrode finger pitch of the IDT electrode is denoted as &#x3bb;, at least two of the elastic wave resonators have the different wavelengths. In two of the elastic wave resonators having different wavelengths, a film thickness of the IDT electrode in the elastic wave resonator having the longer wavelength is not greater than that of the IDT electrode in the elastic wave resonator having the shorter wavelength. Film thicknesses of the IDT electrodes in at least two of the elastic wave resonators are different from each other. The elastic wave device utilizes a Rayleigh wave.

Elastic wave device

An elastic wave device includes first and second IDT electrodes provided over a principal surface of a piezoelectric substrate. The first IDT electrode is provided directly on a principal surface of the piezoelectric substrate and the second IDT electrode is provided over the principal surface with a first dielectric layer interposed therebetween. A second dielectric layer extends to upper portions of the first and second IDT electrodes. A wiring electrode passes over the second dielectric layer and extends to the upper portions of the first and second IDT electrodes. Respective angles between first and second side surfaces of the second dielectric layer and the principal surface of the piezoelectric substrate are smaller than an angle between a side surface of the first dielectric layer and the principal surface of the piezoelectric substrate.

Elastic wave device, high-frequency front end circuit, and communication device

An acoustic wave device includes a support substrate having a central region and a surrounding region located around the central region, a silicon oxide film that is located in the central region directly or indirectly and that has a side surface, a piezoelectric layer that is provided on the silicon oxide film and that has a first principal surface and a second principal surface, an excitation electrode provided on at least one of the first principal surface and the second principal surface, a cover film provided to cover the entire side surface of the silicon oxide film, a resin layer that is provided in the surrounding region and that is provided to cover the side surface of the silicon oxide film from above the cover film, and a wiring electrode that is electrically connected to the excitation electrode and that extends from the piezoelectric layer to the resin layer.

An elastic wave device includes interdigital transducer electrodes on a piezoelectric substrate and wires electrically connected to the interdigital transducer electrodes. The wires include a first wire and a second wire. The device further includes an interlayer insulating film made from an inorganic dielectric material and covering a portion of the first wire. A portion of the second wire bridges a portion of the first wire with the interlayer insulating film provided therebetween. In a region, in a bridged area, where the second wire extends from a region on an outer side portion of the interlayer insulating film to above the interlayer insulating film, first auxiliary wire electrodes are provided on the piezoelectric substrate, such that when viewed in plan view, the first auxiliary wire electrodes at least partially overlap with the second wire and extend to within the interlayer insulating film.

Elastic wave device and manufacturing method thereof

A module device includes electrode lands and signal wires on an upper surface defining one main surface of a module substrate. A filter chip is mounted on the module substrate. The filter chip includes first bumps connected to a signal potential, second bumps connected to a ground potential, and a third bump not electrically connected to a functional electrode portion. In a mount region, the third bump which is a floating bump is electrically connected to the signal wire.

Module device

A ladder filter includes a piezoelectric substrate, an insulating film on the piezoelectric substrate, first and second electrodes provided on the piezoelectric substrate and including a pair of busbars and plurality of electrode fingers, a first line electrode at least a portion of which is defined by the busbar at one side of the first electrode, a second line electrode at least a portion of which is defined by the busbar at one side of the second electrode, and a third line electrode laminated on the second line electrode. The first line electrode and the second line electrode are electrically connected to different electric potentials. The first line electrode is separated from the second line electrode by a predetermined distance. At least a portion of the third line electrode is overlapped with at least a portion of the first line electrode with the insulating film interposed therebetween in a laminating direction.

Ladder filter and duplexer

In an elastic wave filter device, a package substrate is provided with an elastic wave filter chip defining a ladder circuit including a plurality of series arm resonators and a plurality of parallel arm resonators, and a first inductance connected in parallel with at least one of the series arm resonators and a second inductance connected between at least one of the parallel arm resonators and a ground potential. The first inductance and the second inductance provided in the package substrate, and the first inductance is magnetically coupled to the second inductance to shift a frequency position of an attenuation pole.

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Nagaokakyo, Japan

Akira Michigami