Fujitsu Corporation

Fujitsu Media Devices Limited

Taiyo Yuden Co., Ltd.

National Institute of Advanced Industrial Science and Technology

Taiyo Yudenco., Ltd.

Fujitsu Media Devices Limted

Masanori Ueda

Tokihiro Nishihara

Masafumi Iwaki

Shinji Taniguchi

Tsuyoshi Yokoyama

Shogo Inoue

Takashi Matsuda

Jun Tsutsumi

Motoaki Hara

Takeshi Sakashita

Osamu Kawachi

Michio Miura

Go Endo

Satoru Matsuda

Osamu Ikata

Seiichi Mitobe

Gou Endoh

Yoshiro Fujiwara

Yasuhide Iwamoto

Yoshio Satoh

Motoyuki Tajima

Suguru Warashina

Kenya Hashimoto

Tsutomu Miyashita

Noboru Wakatsuki

Yasufumi Kaneda

Masatsune Yamaguchi

Takuya Abe

Yasuyuki Saitou

Haruyuki Matsunaga

Akira Suga

Masahiko Imai

Hiroshi Hasegawa

Masuji Sato

Hiroyuki Furusato

Kazushi Hashimoto

Ken-ya Hashimoto

Hisanori Ehara

Masufumi Iwaki

Kiyohide Misawa

Akira Tanaka

Naoyuki Mishima

Toshio Nishizawa

Hideki Takagi

Takayuki Yamaji

Shunichi Aikawa

Hideki Ohmori

Yasuo Ebata

Masaya Suwa

Jiansong Liu

Koichi Hatano

Nobuo Hirasawa

Hisashi Sawada

Tatsuya Omori

Takumi Kooriike

Yasutomo Tanaka

Hiroyoshi Yasuda

Toru Uemura

Kunihisa Wada

Gou Endou

Osamu Kawauchi

Kunio Yamashiro

An acoustic wave device includes: a support substrate; a single piezoelectric substrate that is located on the support substrate and is single-crystal; first electrodes located on a first surface of the piezoelectric substrate; second electrodes located on a second surface of the piezoelectric substrate; and an acoustic mirror that is bonded on the support substrate, is located between the support substrate and the first electrodes in resonance regions where the first electrodes and the second electrodes face each other across at least a part of the piezoelectric substrate, is not located between the support substrate and the first electrodes in at least a part of a region between the resonance regions, and reflects an acoustic wave propagating through the piezoelectric substrate.

Acoustic wave device and method of fabricating the same, filter, and multiplexer

In a filter, two parallel resonators that are adjacent to each other are connected, in parallel, to a first portion of the signal line that connects a pair of two adjacent series resonators, at least one parallel resonator is connected, in parallel, to a second portion of the signal line that connects a different pair of two adjacent series resonators, a first inductor is connected to one parallel resonator of said two parallel resonators in series, a second inductor is connected to one parallel resonator of said at least one parallel resonator in series, a third inductor is connected to said two parallel resonators and said at least one parallel resonator, the first and third inductors' total inductance is different from the second and third inductor's total inductance.

Filter, duplexer and communication module

A piezoelectric thin film resonator includes a substrate, a lower electrode provided on the substrate, a piezoelectric film provided on the lower electrode, and an upper electrode provided on the piezoelectric film. At least a portion of the upper electrode and that of the lower electrode oppose each other through the piezoelectric film, and at least a portion of the periphery of the upper electrode is reversely tapered.

Piezoelectric thin film resonator, filter, communication module and communication device

The filter includes: a primary transducer connected to a primary terminal; a secondary transducer connected to a plurality of secondary terminals; and a coupling transducer for mechanically coupling the primary transducer and the secondary transducer.

Filter, duplexer, communication module and communication device

An acoustic wave device includes: a substrate; a lower electrode formed on the substrate; at least two piezoelectric films formed on the lower electrode; an insulating film located between the at least two piezoelectric films; and an upper electrode formed on the at least two piezoelectric films, wherein an outer periphery of an uppermost piezoelectric film out of the at least two piezoelectric films in a region in which the lower electrode and the upper electrode face each other is positioned further in than an outer periphery of the upper electrode.

Acoustic wave device

A piezoelectric thin film resonator includes: a substrate; a piezoelectric film located on the substrate; a lower electrode and an upper electrode located to sandwich the piezoelectric film; a load film formed from patterns in a resonance region in which the lower electrode and the upper electrode face each other across the piezoelectric film, wherein the patterns are formed so as to surround a center of the resonance region and intersect with a pathway extending from the center to an outer periphery of the resonance region.

Piezoelectric thin film resonator and filter

A method for manufacturing an acoustic wave device includes: bonding a piezoelectric substrate to a first surface of a first support substrate; thinning the piezoelectric substrate after the bonding to thus form a piezoelectric layer; forming a first electrode on a first surface of the piezoelectric layer; forming holes in the first support substrate located below the first electrode; and bonding a second support substrate to a second surface of the first support substrate opposite to the first surface after the forming of holes.

Method for manufacturing acoustic wave device

A filter includes a plurality of primary resonators connected to a serial arm, a plurality of secondary resonators connected to a parallel arm, a primary inductor connected to at least one of the plurality of primary resonators and a secondary inductor connected to at least one of the plurality of secondary resonators. The primary inductor is arranged so as not to be connected to a path between the secondary resonator to which the secondary inductor is connected in parallel and the primary resonator that is connected to the secondary resonator to which the secondary inductor is connected in parallel.

An electronic circuit includes a plurality of duplexers that are coupled to an antenna terminal and have a pass band different from each other and a plurality of acoustic wave filters that are respectively coupled between the antenna terminal and the plurality of the duplexers, wherein filter characteristics of a first acoustic wave filter of the plurality of the acoustic wave filters are set so as to allow passage of a signal in both a pass band for transmitting and a pass band for receiving of a first duplexer of the plurality of the duplexers that is coupled to the first acoustic wave filter and suppress passage of a signal in both a pass band for transmitting and a pass band for receiving of a second duplexer of the plurality of the duplexers that is different from the first duplexer.

Electronic circuit and electronic module

A piezoelectric thin-film resonator includes: a lower electrode provided on a substrate; a piezoelectric film that is provided on the lower electrode and includes at least two layers; an upper electrode that is provided on the piezoelectric film and has a region sandwiching the piezoelectric film with the lower electrode and facing the lower electrode; and an insulating film that is provided in a region in which the lower electrode and the upper electrode face each other and between each of the at least two layers, wherein an upper face of the insulating film is flatter than a lower face of the insulating film.

Piezoelectric thin-film resonator and method for manufacturing the same

A surface acoustic wave device includes a piezoelectric substrate having a first surface on which comb-like electrodes, first pads connected thereto, and a first film are provided. The first film is located so as to surround the comb-like electrodes. A base substrate has a second surface on which second pads joined to the first pads and a second film joined to the first film are provided. The first and second films joined by a surface activation process define a cavity in which the comb-like electrodes and the first and second pads are hermetically sealed.

Surface acoustic wave device and method of fabricating the same

An acoustic wave device includes a main resonator and a sub resonator each having a substrate, a lower electrode provided on the substrate, a piezoelectric film provided on the lower electrode, and an upper electrode provided on an upper side of the piezoelectric film. A frequency control film is provided on an upper side of a resonance area in which the upper electrode and the lower electrode face each other in at least one of the main resonator and the sub resonator. The frequency control film has multiple convex patterns, and the convex patterns are arranged with a common pitch for spurious adjustment and with different areas in the main resonator and the sub resonator.

Acoustic wave device having a frequency control film

A ladder type filter includes series resonators S&#x2dc;Sconnected in series between an input terminal In and an output terminal Out, parallel resonators P&#x2dc;Pconnected in parallel between the input terminal In and the output terminal Out, a resonator RP connected in series with the series resonators S&#x2dc;Sbetween the input terminal and the output terminal, the resonator RP having a resonance frequency lower than resonance frequencies of the series resonators S&#x2dc;Sand an inductor Lp connected in parallel with the resonator. According to the present ladder filter, signals having frequencies away from the pass band can be suppressed by an attenuation pole formed by the inductor. It is further possible to suppress the insertion loss in the pass band by the resonator.

Filter, duplexer and electronic device

A method of manufacturing an elastic wave device is provided with a lamination step of forming, on a substrate (), a plurality of elastic wave devices, each of which includes a lower electrode (), a piezoelectric film (), and an upper electrode (); a measuring step for measuring the operation frequency distribution of the elastic wave devices on the substrate (); and an adjusting step for forming an adjusting region, in which the thickness of the elastic wave device is different from the thicknesses of other portions in a resonance portion of each elastic wave device, corresponding with the distribution of the operation frequencies. The adjusting region is formed so that the size of the area of the adjusting region of the resonator portion of each elastic wave device is different in accordance with the operation frequency distribution that is measured. Thus, the frequency characteristics of the elastic wave devices are easily adjusted by a small number of steps.

Elastic wave device and method for manufacturing the same

The filter includes one or more series resonators and one or more parallel resonators. An inductance is connected in series to at least a parallel resonator of the parallel resonators, and a antiresonance frequency of the parallel resonator to which the inductance is connected in series is equal to or higher than that of the series resonators. The duplexer, the communication module and the communication device are provided with the filter.

Filter, duplexer, communication module, communication device

Growing community of inventors

Kawasaki, Japan

Masanori Ueda