Murata Manufacturing Co., Ltd.

Murata Manufacturingco., Ltd.

Katsuya Daimon

Yasumasa Taniguchi

Hideki Iwamoto

Masato Araki

Tetsuya Kimura

Takashi Yamane

Sho Nagatomo

Takuya Koyanagi

Akira Michigami

Yasuharu Nakai

Daisuke Tamazaki

Masakazu Mimura

Tsutomu Takai

Koji Yamamoto

Shou Nagatomo

Toshimaro Yoneda

Ryo Nakagawa

Kazuhiro Takigawa

Yohei Konaka

Koji Miyamoto

Hiromu Okunaga

Takashi Ogami

Hidetaro Nakazawa

An acoustic wave device includes a support substrate, a piezoelectric film, and an IDT electrode. When a wavelength defined by an electrode finger pitch of the IDT electrode is λ, a thickness of the piezoelectric film is about 1λ or less. The piezoelectric film has crystal axes. The support substrate includes first and second silicon layers. A plane orientation of the first and second silicon layers is (100), (110), or (111). When angles α1 and β2 are defined between the plane orientations of the first and second silicon layers and the crystal axes, each of the angles α1 and α2 is one of three types of angles of an angle α, an angle α, and an angle α. A type of the angle α1 is different from a type of the angle α2 and/or a value of the angle α1 is different from a value of the angle α2.

Acoustic wave device

An acoustic wave device includes an IDT electrode and reflector electrodes on or above a piezoelectric substrate. A region in which first and second electrode fingers of the IDT electrode overlap each other in an acoustic wave propagation direction defines an intersection region. The intersection region includes a center region and first and second edge regions on both sides of the center region. Dielectric films extend from the first and second edge regions to outer side regions in the acoustic wave propagation direction of the reflector electrodes via the reflector electrodes.

In an acoustic wave device, a piezoelectric layer is provided directly or indirectly on a support substrate, an IDT electrode is provided on the piezoelectric layer, an overlap region includes a middle region and first and second edge regions, and first and second conductive layers are provided on a second main surface of the piezoelectric layer to overlap at least some portions of the first and second edge regions in plan view and at least some portions of first and second busbars in plan view.

Acoustic wave device and ladder filter

An acoustic wave device includes a piezoelectric layer including lithium tantalate or lithium niobate, a dielectric film on the piezoelectric layer, the dielectric film including a dielectric material having a higher dielectric constant than that of the lithium tantalate or lithium niobate, and an IDT electrode on the dielectric film.

An acoustic wave device includes an IDT electrode on a piezoelectric layer. The IDT electrode includes first and second electrode fingers made of an alloy film including Al and at least one of Cu, Mg, Ag, or Nd, and an overlap region in which the first and second electrode fingers overlap when viewed in the direction of propagation of acoustic waves. The overlap region includes a central region and first and second edge regions outside the central region on opposite sides in the direction in which the first and second electrode fingers extend. In at least one of the first and second electrode fingers, a concentration of the at least one of Cu, Mg, Ag, or Nd in at least a portion of the first and second edge regions is higher than that in the central region.

Acoustic wave device with electrode fingers made of an alloy

An acoustic wave device includes first and second electrode fingers on a piezoelectric layer, and third and fourth electrode fingers and a plurality of fourth electrode fingers are provided on the piezoelectric layer. A connection section includes second and third busbars. The second busbar is on the piezoelectric layer and is connected to one end of each of the second electrode fingers. The third busbar is on the piezoelectric layer and is connected to one end of each of the third electrode fingers. A stress relaxation layer is between the connection section and the piezoelectric layer. The stress relaxation layer does not extend to any of a gap between each of the first electrode fingers and the second busbar and a gap between each of the fourth electrode fingers and the third busbar in a plan view from a thickness direction of a support substrate.

An acoustic wave device includes a piezoelectric layer and first and second electrodes facing each other in a direction crossing a thickness direction of the piezoelectric layer. The acoustic wave device utilizes a bulk wave of a thickness slip first-order mode. The acoustic wave device includes first and second resonators. Each of the first and second resonators includes the first and second electrodes, and a setting portion including a setup region where the first and second electrodes are provided in the piezoelectric layer. The thickness of each of the first and second resonators excludes the thickness of the first and second electrodes included in the resonator. The thickness of the first resonator is different from the thickness of the second resonator.

An acoustic wave device includes an acoustic wave resonator and a longitudinally coupled acoustic wave resonator filter, in which the longitudinally coupled acoustic wave resonator filter is shorter than the acoustic wave resonator in terms of a length of first and second edge regions that is a dimension along an extending direction of electrode fingers of the first and second edge regions in an IDT electrode.

An acoustic wave element includes a piezoelectric substrate, an IDT electrode on the piezoelectric substrate, and a reflector. The IDT electrode includes plural electrode fingers, and the reflector includes plural reflector electrode fingers. In a case where IRGAP is an IDT-reflector gap that is a distance between a center of the electrode finger located closest to the reflector and a center of the reflector electrode finger located closest to the IDT electrode, and λis a reflector wave length that is twice a repetition pitch of the reflector electrode fingers, a ratio of about 0.25≤IRGAP/λ≤about 0.44 is satisfied, and the reflector wave length is longer than an IDT wave length that is a repetition pitch of the electrode fingers.

Acoustic wave element, acoustic wave filter device, and multiplexer

An acoustic wave filter includes acoustic wave resonators including a piezoelectric substrate and an IDT electrode including first and second electrode fingers. An intersecting region of the first and second electrode fingers includes a central region and first and second edge regions on outer side portions of the central region. An acoustic velocity in the first and second edge regions is lower than that in the central region, and the acoustic wave resonators include a first acoustic wave resonator with a width in the first and second edge regions larger than a width in the central region, and a second acoustic wave resonator including at least one of an acoustic velocity reducing film and an acoustic velocity increasing film in the central region, such that an acoustic velocity in the first and second edge regions is lower than acoustic velocity in the center region.

Acoustic wave filter

An acoustic wave device includes a silicon support substrate, a silicon nitride film on the support substrate, a silicon oxide film on the silicon nitride film, a piezoelectric layer on the silicon oxide film and using Y-cut X-SAW propagation lithium tantalate, and an IDT electrode on the piezoelectric layer. A film thickness of the piezoelectric layer is equal to or less than about 1λ, Euler angles of the piezoelectric layer are (0±5°, θ, 0±5°) or (0±5°, θ, 180±5°), θ in the Euler angles of the piezoelectric layer is about 95.5°≤θ<117.5° or about −84.5°≤θ<−62.5°, and a relationship between θ in the Euler angles of the piezoelectric layer and a film thickness of the silicon nitride film is a combination shown in Table 1 or Table 2.

An acoustic wave device includes a support substrate, a piezoelectric layer, and an IDT electrode. The piezoelectric layer is over the support substrate. The IDT electrode is on the piezoelectric layer, and includes a plurality of electrode fingers. An intersecting width of the plurality of electrode fingers is equal to or smaller than about 5λ.

An acoustic wave device includes a piezoelectric substrate, a first interdigital transducer (IDT) electrode, reflectors on both sides of the first IDT electrode in a propagation direction of an acoustic wave, and a second IDT electrode facing the first IDT electrode with a reflector interposed therebetween. The first and second IDT electrodes include first and second intersecting areas in which electrode fingers overlap in the propagation direction. The first and second intersecting areas overlap in the propagation direction. A third busbar of the second IDT electrode is coupled to a first busbar of the first IDT electrode. A fourth busbar of the second IDT electrode is coupled to a ground potential. A resonant frequency of the second IDT electrode is in a frequency band of an interference wave signal.

Acoustic wave device, filter device, and multiplexer

An acoustic wave device includes an energy confinement layer, a piezoelectric layer made of Y-cut X-propagation lithium tantalate having a cut angle in a range from about −10° to about 65°, and an IDT electrode. Electrode fingers of the IDT electrode include an Al metal layer and a high acoustic impedance metal layer having a Young's modulus equal to or more than about 200 GPa and an acoustic impedance higher than Al. The high acoustic impedance metal layer is closer to the piezoelectric layer than the Al metal layer. A wavelength specific film thickness tof the piezoelectric layer is expressed by t≤1λ. The total of normalized film thicknesses obtained by normalizing the film thickness of each layer of the electrode finger by a density and Young's modulus of the Al metal layer satisfies T≤0.1125t+0.0574.

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Katsuya Daimon