Fujitsu Corporation

Other

Fujitsu Media Devices Limited

Taiyo Yuden Co., Ltd.

Fujitsu Towa Electron Limited

National Institute of Advanced Industrial Science and Technology

Yoshio Satoh

Osamu Ikata

Takashi Matsuda

Tsutomu Miyashita

Tokihiro Nishihara

Hiroshi Ishikawa

Jun Tsutsumi

Masanori Yachi

Hidema Uchishiba

Mitsuo Takamatsu

Kazunari Komenou

Masanori Ueda

Yoshitaka Takahashi

Tadashi Nakatani

Fumihiko Nakazawa

Satoshi Sano

Kazutsugu Kikuchi

Shinji Taniguchi

Michio Miura

Makoto Ohashi

Sumio Yamada

Taisei Irieda

Kazuo Matsuda

Nobuo Hirasawa

Takeshi Sakashita

Masafumi Iwaki

Tsuyoshi Yokoyama

Shogo Inoue

Hiroshi Tanaka

Yu Yonezawa

Noboru Wakatsuki

Yoshiro Fujiwara

Masaaki Ono

Suguru Warashina

Masumi Kida

Mitsuo Takanatsu

Hajime Taniguchi

Yuji Takahashi

Osamu Kawachi

Fumio Yamagishi

Takashi Katsuki

Kazuya Masu

Hideki Takagi

Hideki Ohmori

Arata Ejiri

Tsuguto Maruyama

Hidetaro Nakazawa

Tabito Tanaka

Takeyasu Yanase

Mamoru Ishida

Kazushi Hashimoto

Atsushi Machida

Kazutugu Kikuchi

Seiichi Hata

Hidenori Fukushima

Akira Shimokohbe

Tsuyoshi Ogasawara

Satoshi Miyamoto

Ivan Dimitrov Avramov

An acoustic wave device includes: a piezoelectric substrate; electrodes sandwiching the piezoelectric substrate and exciting a thickness shear vibration in the piezoelectric substrate; and an edge region that is a region surrounding a center region of a resonance region, wherein a first region of the edge region is located on both sides of the center region in a first direction substantially parallel to a displacement direction of a thickness shear vibration, a second region of the edge region is located on both sides of the center region in a second direction substantially perpendicular to the first direction, a width of the second region is different from a width of the first region, and acoustic velocities of acoustic waves in the piezoelectric substrate in the first and second regions are less than that in the piezoelectric substrate in the center region.

Acoustic wave device, filter, and multiplexer

An acoustic wave device includes: a Y-cut X-propagation lithium tantalate substrate having a cut angle of 5&#xb0; or greater and 18&#xb0; or less; and a grating electrode that is formed of one or more metal films stacked on the lithium tantalate substrate, a number of the one or more metal films being n (n is a natural number), excites an acoustic wave, and meets a condition: where &#x3c1;i represents a density of each metal film of the one or more metal films, hi represents a film thickness of the each metal film, &#x3c1;represents a density of Mo, and &#x3bb; represents a pitch.

An acoustic wave device includes: a first resonator that includes a first piezoelectric substance, and first lower and upper electrodes sandwiching the first piezoelectric substance in a direction of a c-axis orientation or a polarization axis of the first piezoelectric substance; and a second resonator that is located closer to a signal input terminal than the first resonator is, is connected in series to the first resonator, includes a second piezoelectric substance, and second lower and upper electrodes sandwiching the second piezoelectric substance so that an electrode in a direction of the c-axis orientation or a polarization axis of the second piezoelectric substance has an electric potential identical to an electric potential of an electrode of the first resonator in the direction of the c-axis orientation or the polarization axis of the first piezoelectric substance, and has an antiresonant frequency less than an antiresonant frequency of the first resonator.

Acoustic wave device

An acoustic wave device includes: a substrate; an acoustic reflection layer located in or on the substrate and including an air gap, or an acoustic mirror; a piezoelectric film located on the acoustic reflection layer; lower and upper electrodes located on the acoustic reflection layer so as to sandwich the piezoelectric film so that resonance regions are located within the acoustic reflection layer and share the acoustic reflection layer, one of the lower and upper electrodes being divided, another one of the lower and upper electrodes being not divided, the lower and upper electrodes facing each other across the piezoelectric film in each of the resonance regions; and an insertion film located between the lower and upper electrodes, located in at least a part of an outer peripheral region of each of the resonance regions, and being not located in a center region of each of the resonance regions.

An acoustic wave resonator includes: a piezoelectric substrate; and an IDT located on the piezoelectric substrate and including a pair of comb-shaped electrodes facing each other, each of the pair of comb-shaped electrodes including a grating electrode exciting an acoustic wave and a bus bar to which the grating electrode is connected, wherein an anisotropy coefficient in a cross region where the grating electrodes of the pair of comb-shaped electrodes cross each other is positive; an anisotropy coefficient in a gap region located between a tip of the grating electrode of one of the pair of comb-shaped electrodes and the bus bar of the other is less than the anisotropy coefficient in the cross region, and an acoustic velocity of an acoustic wave propagating through the gap region is equal to or less than an acoustic velocity of an acoustic wave propagating through the cross region at an antiresonant frequency.

Acoustic wave resonator, filter, and duplexer

An acoustic wave device includes: a piezoelectric thin film resonator that is connected between a first node and a second node; and a resonant circuit that is connected in parallel with the piezoelectric thin film resonator between the first node and the second node, and has a resonant frequency fthat meets a condition of 2&#xd7;fa&#xd7;0.92&#x2264;fwhere fa represents an antiresonant frequency of the piezoelectric thin film resonator.

A filter includes: an input terminal; an output terminal; and a ladder circuit that includes one or more series acoustic wave resonators connected in series between the input terminal and the output terminal and one or more parallel acoustic wave resonators connected in parallel between the input terminal and the output terminal, and in which characteristic impedance of at least one point in a pathway between the input terminal and the output terminal in a passband is greater than at least one of input impedance of the input terminal and output impedance of the output terminal in the passband.

Filter and multiplexer

An acoustic wave device of the present application includes a piezoelectric substrate (), interdigital transducer electrodes () formed on the piezoelectric substrate (), and an SiOfilm () formed so as to cover the electrodes (). The acoustic wave device also includes a displacement adjustment film () formed on the SiOfilm (), and the displacement adjustment film () is formed from a substance whose acoustic velocity is slower than that of the substance forming the SiOfilm (). According to this configuration, it is possible to suppress unnecessary waves as well as improve temperature characteristics. Also, by mounting such an acoustic wave device in a communication module or communication apparatus, it is possible to achieve an improvement in reliability.

Planar surface acoustic wave device, communication module, and communication apparatus

A plurality of excitation elements are disposed on two facing sides of a quadrilateral detection range in a non-piezoelectric substrate, and a plurality of receiving elements are disposed on the other two sides of the detection range so as to face the excitation elements respectively. Surface acoustic waves are transmitted from the respective plurality of excitation elements in two diagonal directions of the detection range respectively, and the surface acoustic waves from the two diagonal directions are received by the respective receiving elements, so that a position of an object in contact with the substrate is detected based on received results in the receiving elements.

Touch panel device

A method of manufacturing a surface acoustic device that has a surface acoustic wave filter including comb-like electrodes, electrode pads, and wiring patterns formed on a joined substrate produced by joining a piezoelectric substrate and a supporting substrate to each other. This method includes the steps of: activating at least one of the joining surfaces of the piezoelectric substrate and the supporting substrate; and joining the piezoelectric substrate and the supporting substrate in such a manner that the activated joining surfaces face each other.

Method and manufacturing surface acoustic wave device

A film bulk acoustic resonator includes: a piezoelectric thin film that is formed on a principal surface of a substrate; and a lower electrode and an upper electrode that are arranged to sandwich the piezoelectric thin film. In this film bulk acoustic resonator, the piezoelectric thin film is made of aluminum nitride, and at least one of the lower electrode and the upper electrode contains a ruthenium or ruthenium-alloy layer.

Film bulk acoustic resonator and method of producing the same

A plurality of excitation elements, each including an IDT and a piezoelectric film, for exciting, respectively, surface acoustic waves, each having a unique center frequency, are formed on one end of a non-piezoelectric substrate, a plurality of receiving elements, each including an IDT and a piezoelectric film, for receiving, respectively, surface acoustic waves, each having a unique center frequency, are formed on the other end of the non-piezoelectric substrate to face the excitation elements, respectively, the center frequencies of the IDTs of the facing excitation element and receiving element are equal, the center frequencies of the IDTs of the excitation elements next to each other are different, and surface acoustic waves are propagated across the non-piezoelectric substrate, between the facing excitation elements and receiving elements so as to detect the position of an object in contact with the non-piezoelectric substrate, based on received results in the receiving elements.

A SAW filter includes a first SAW resonator having a pair of terminals and a predetermined resonance frequency (f), the first SAW resonator being provided in a parallel arm of the SAW filter. A second SAW resonator has a pair of terminals and a predetermined resonance frequency (f) approximately equal to a predetermined antiresonance frequency of the first SAW resonator (f). The second SAW resonator is provided in a series arm of the SAW filter. An inductance element is connected in series to the first SAW resonator.

Surface acoustic wave filter

A surface acoustic wave device includes: a piezoelectric substrate that has two or more resonators formed on a surface; and a supporting substrate that is joined to another surface of the piezoelectric substrate. In this surface acoustic wave device, at least two of the resonators have exciting portions that overlap each other in the direction of propagating surface acoustic waves, and at least a part of the piezoelectric substrate is removed or modified to have different properties between at least one pair of overlapping resonators among the resonators having the overlapping portions.

Surface acoustic wave device and method of manufacturing the same

An angular velocity sensor is provided that includes a frame, an oscillator and torsion bars that connect the oscillator to the frame. The frame, the oscillator and the torsion bar are formed integral with each other by etching a material substrate in the thickness direction of the substrate. The oscillator, configured in the form of an H, includes a support, two first arms and two second arms. These arms extend from the support in an arm-extending direction perpendicular to the thickness direction of the substrate. The oscillator includes a mounting surface that is provided with a piezoelectric driver for generating in-plane oscillation of the oscillator, and with a piezoelectric detector for detecting out-of-plane oscillation of the oscillator.

Angular velocity sensor

Growing community of inventors

Kawasaki, Japan

Yoshio Satoh