Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Minolta Company, Ltd.

Panasonic Intellectual Property Management Co., Ltd.

Ryoichi Takayama

Hideo Torii

Atsushi Tomozawa

Eiji Fujii

Satoru Fujii

Takeshi Kamada

Isaku Kanno

Yoshihiro Tomita

Taku Hirasawa

Akiko Murata

Masumi Hattori

Shigenori Hayashi

Hidekazu Nakanishi

Takashi Hirao

Toru Sakuragawa

Kozo Murakami

Yukihiko Ise

Masayuki Okano

Tetsuo Kawasaki

Hiroyuki Nakamura

Yuki Satoh

Masatoshi Kitagawa

Koji Nomura

Kazuki Komaki

Osamu Watanabe

Yukio Iwasaki

Takashi Deguchi

Kenji Tomita

Akira Tokushima

Nozomu Ueshiba

Satoshi Fujii

Masafumi Kobune

Masaki Aoki

Masaya Nakatani

Yoshiharu Yamamoto

Koji Ikeda

Motonobu Yoshikawa

Osamu Kawasaki

Hisahito Ogawa

Kenji Iijima

Masayoshi Miura

Yosuke Hamaoka

Yuji Takashima

Junko Asayama

Eiichiro Tanaka

Shigeyuki Takao

Atsushi Abe

Katsumasa Miki

Shunichi Seki

Keizaburo Kuramasu

Yasuhiko Horio

Hiroki Moriwake

Toshio Sugawa

Ichiro Ueda

Yasuhiko Yokota

Yuki Sato

Koji Hasegawa

Katsuya Fujii

Ken Kamata

Eiji Fuji

A surface acoustic wave device includes a substrate including lithium niobate; a IDT being provided on an upper surface of the substrate and including a plurality of electrode fingers; and a protective film covering the IDT and having an uneven shape on an upper surface thereof. When a pitch width of one pitch of the IDT is p, a width of one of the electrode fingers is p, a width between the electrode fingers is p, and a thickness of the IDT is h, following relations are satisfied, p+p=p, and h/(2&#xd7;p)&#x2267;4.5%. With this configuration, an appropriate reflection characteristic is realized, and the surface acoustic wave device having excellent temperature coefficient of frequency and electrical characteristic can be obtained.

Surface acoustic wave device, surface acoustic wave filter and antenna duplexer using the same, and electronic equipment using the same

A plurality of surface acoustic wave resonators including a comb electrode and a grating reflector are coupled on a piezoelectric substrate. Dielectric film is formed on the surface of at least one surface acoustic wave resonator. No dielectric film is formed on the surface of at least one other surface acoustic wave resonator. Thus, a SAW filter where the insertion loss into a pass band is small, the steepness is sufficient, and the band is wide can be obtained.

Surface acoustic wave filter, and saw duplexer

In a piezoelectric element, an adhesive layeris provided on a substrate, a first electrode layermade of a noble metal containing titanium or titanium oxide is provided on the adhesive layer, and an orientation control layerthat is preferentially oriented along a (100) or (001) plane is provided on the first electrode layer. In the vicinity of a surface of the orientation control layerthat is closer to the first electrode layer, a (100)- or (001)-oriented region extends over titanium or titanium oxide located on one surface of the first electrode layerthat is closer to the orientation control layer, and the cross-sectional area of the region in the direction perpendicular to the thickness direction gradually increases in the direction away from the first electrode layertoward the opposite side. Further, a piezoelectric layerthat is preferentially oriented along a (001) plane is provided on the orientation control layer

Piezoelectric element, ink jet head, angular velocity sensor, method for manufacturing the same, and ink jet recording apparatus

In a piezoelectric elementa first electrode layermade of an alloy of at least one metal selected from the group consisting of cobalt, nickel, iron, manganese and copper and a noble metal is formed on a silicon substrateand a piezoelectric layermade of a rhombohedral or tetragonal perovskite oxide (e.g., PZT) is formed on the first electrode layerso that the piezoelectric layeris preferentially oriented along the (001) plane.

In a surface acoustic wave (SAW) device, such as a SAW resonator or a SAW filter, loss is minimized and steep characteristics are improved. IDT electrodes and a reflector are provided to a piezoelectric substrate cut out at a cut-angle which allows the substrate to excite a leaky surface acoustic wave (LSAW). The IDT electrodes have a given film thickness and a given pitch 'p' of finger-electrodes. A phase velocity of the SAW is reduced to slower than a phase velocity 'vb'of a slow shear wave propagating on the piezoelectric substrate, and a resonance frequency &#x201c;f&#x201d; satisfies a relation of 2&#xd7;p&#x2266;vb/f. This structure allows the use of a Rayleigh surface acoustic wave (RSAW) which does not produce propagation loss, and improving insertion-loss and steep characteristics from those of a conventional SAW device using the LSAW.

Surface acoustic wave device, and mobile communication device and sensor both using same

In a piezoelectric element, a first electrode layermade of an alloy of at least one metal selected from the group consisting of cobalt, nickel, iron, manganese and copper and a noble metal is formed on a silicon substrate, and a piezoelectric layermade of a rhombohedral or tetragonal perovskite oxide (e.g., PZT) is formed on the first electrode layerso that the piezoelectric layeris preferentially oriented along the (001) plane.

Piezoelectric element, ink jet head, angular velocity sensor, manufacturing method thereof, and ink jet type recording apparatus

To manufacture a compact and high-performance thin-film piezoelectric bimorph element at low cost, first and second piezoelectric thin films () are formed by sputtering on the both surfaces of a metal thin plate () which are opposing relation to each other along the thickness thereof, while the respective states of polarizations of the first and second piezoelectric thin films () are controlled. A pair of electrode films () are formed on the respective surfaces of the first and second piezoelectric thin films () opposite to the metal thin plate ().

Method for controlling a direction of polarization of a piezoelectric thin film

A piezoelectric thin film can achieve a large piezoelectric displacement. A chemical composition of the piezoelectric thin film is expressed by Pb(ZrTi)O(0.2&#x2266;a&#x2266;0.6 and 0.50&#x2266;x&#x2266;0.62). The crystal structure of the piezoelectric thin film is a mixture of a perovskite columnar crystal region () having an ionic defect in which a portion of the constitutive elements of an oxygen ion, a titanium ion, and a zirconium ion is missing and a perovskite columnar crystal region () of stoichiometric composition having no ionic defect. This configuration allows a residual compressive stress in the crystal to be relaxed by the perovskite columnar crystal region () having an ionic defect, thus achieving a large piezoelectric displacement (displacement amount).

PIEZOELECTRIC THIN FILM AND METHOD FOR PREPARATION THEOF, AND PIEZOELECTRIC ELEMENT HAVING THE PIEZOELECTRIC THIN FILM, INK-JET HEAD USING THE PIEZOELECTRIC ELEMENT, AND INK-JET RECORDING DEVICE HAVING THE INK-JET HEAD

A piezoelectric element includes a first electrode layerprovided on a substrateand made of a noble metal to which at least one additive selected from the group consisting of Mg, Ca, Sr, Ba, Al and oxides thereof is added, an orientation control layerprovided on the first electrode layerand made of a cubic or tetragonal perovskite oxide that is preferentially oriented along a (100) or (001) plane, and a piezoelectric layerprovided on the orientation control layerand made of a rhombohedral or tetragonal perovskite oxide that is preferentially oriented along a (001) plane.

In a surface acoustic wave (SAW) filter including a substrate and an electrode formed on the substrate, the electrode includes a base layer, a first metal layer made of a metal consisting of Al or consisting mainly of Al, and having a given orientation relative to the substrate, a second layer for preventing the first metal layer from migration of Al atoms occurring in vertical to the substrate, and a third layer for adjusting a thickness of the layer. In this SAW filter having an arbitrary layer thickness, the layer hardly causes grain boundary diffusion, and grains of the layer can be made fine for effective resistance to stress. Thus, in this SAW filter, the migration of the Al atoms of the electrode that is associated with the SAW propagation-induced stress imposed on the electrode is inhibited. Accordingly, the filter exhibits excellent resistance against electric power.

Surface acoustic wave filter utilizing a layer for preventing grain boundary diffusion

An antenna duplexer has a power durability to a signal input from an antenna terminal and has stable characteristics. The antenna duplexer includes an input terminal, a transmission filter including a surface acoustic wave (SAW) filter having an input port connected to the input terminal, a phase shifter having an input port connected to an output port of the transmission filter, a reception filter having an input port connected to an output port of the phase shifter, an output terminal connected to the output port of the reception filter, and an antenna terminal connected between the transmission filter and the phase shifter. The transmission filter has a power durability at the output port of the filter, being equal to or larger than a power durability at the input port of the filter.

Antenna duplexer

In the liquid discharge head for discharging liquid such as ink like the ink jet head, at least a part on a surface of a piezoelectric element on the side of a liquid chamber member (ink chamber member) is composed of a nucleus forming assistance material contained layer containing a material for assisting nucleus forming for growth of plating at the time of forming the liquid chamber member on the surface by means of the electroless plating, and the liquid chamber member is formed on the nucleus forming assistance material contained layer by the electroless plating.

Liquid discharge head and manufacturing method thereof

A small-sized multi-frequency antenna duplexer using surface acoustic wave filters to be applicable to a plurality of frequencies. This antenna duplexer includes two surface acoustic wave (SAW) filters for transmission and reception having passing bands of mutually different frequencies, a phase shift substrate, and a package for accommodating them. The passing band of each antenna duplexer is mutually different from other's passing band. This multi-frequency antenna duplexer includes a plurality of antenna duplexers. In one package, transmitter surface acoustic wave filters, receiver surface acoustic filters, and phase shift substrates are mounted. Thus, the multi-frequency antenna duplexer are reduced in size.

Multi-frequency antenna duplexer

A piezoelectric thin film element D, in which a piezoelectric thin film with first and second electrode films and respectively formed on its opposite surfaces in the thickness direction is held by a hold film , is fabricated by forming each film , and on a film formation substrate 11 and removing the film formation substrate by etching. Even when the hold film is made of material such as resin and therefore exhibits relatively poor adhesion with respect to the other films, the piezoelectric thin film is protected from damage by etchant because the first electrode film which comes into contact with the film formation substrate is formed such that the overall circumference of a peripheral edge portion of the first electrode film laterally extends beyond the lateral surface of the piezoelectric thin film and closely adheres to the hold film

Piezoelectric thin film element, ink jet recording head using such a piezoelectric thin film element, and their manufacture methods

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Osaka, Japan

Ryoichi Takayama