Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Panasonic Intellectual Property Management Co., Ltd.

Tetsuo Kawasaki

Hidekazu Nakanishi

Ryoichi Takayama

Takashi Inoue

Toru Sakuragawa

Ryouichi Takayama

Yukio Iwasaki

Kouji Hasegawa

Hiroyuki Nakamura

Katsu Takeda

Yuki Satoh

Kazunori Nishimura

Tomoya Komatsu

Tomohiro Iwasaki

Katsunori Moritoki

Kazunari Nishihara

Kozo Murakami

Shigeru Tsuzuki

Shunichi Seki

Yukinori Sasaki

Tetsuro Shimamura

Tetsuya Furihata

Yasuhiko Yokota

Koji Hasegawa

Kuniaki Matsushita

An acoustic wave sensor includes a piezoelectric substrate, a transmitting electrode configured to excite a main acoustic wave propagating through a propagation region of an upper surface of the piezoelectric substrate, a receiving electrode configured to receive the propagated main acoustic wave, a first insulating film provided on the propagation region of the upper surface of the piezoelectric substrate, a second insulating film provided on the upper surface of the piezoelectric substrate to cover the first insulating film, and a reaction section provided on the upper surface of the second insulating film above the propagation region. The reaction section is configured to react with an object. A velocity of a transverse wave propagating through the first insulating film is higher than a velocity of a transverse wave propagating through the second insulating film. The acoustic wave sensor described above has high detection sensitivity.

Elastic wave sensor

An electronic part, an object of which is to improve temperature characteristics and electrical properties, includes a substrate (), a comb-type electrode () that is disposed on the upper surface of the substrate (), and a protective film () that covers the comb-type electrode () and has an uneven shape at its top surface. If the pitch width of one pitch in the uneven shape of the protective film () is L, the width of one pitch of a convex portion () of the unevenness in the uneven shape of the protective film () is L, the width of one pitch of a concave portion () thereof is L, the pitch width of one pitch of the comb-type electrode () is p, the width of one of electrode fingers which form the comb-type electrode () is pand the width between the electrode fingers is p, then each parameter is set so that the following expressions are satisfied, L&#x2266;pand L&#x2267;p(herein, the correlations of L&#x2248;p, p+p=p and L+L=L are satisfied).

Electronic part and electronic equipment with electronic part

An electronic part, object of which is to improve temperature characteristics and electrical properties, includes a substrate (), a comb-type electrode () that is disposed on the upper surface of the substrate (), and a protective film () that covers the comb-type electrode () and has an uneven shape at its top surface. If the pitch width of one pitch in the uneven shape of the protective film () is L, the width of one pitch of a convex portion () of the unevenness in the uneven shape of the protective film () is L, the width of one pitch of a concave portion () thereof is Lthe pitch width of one pitch of the comb-type electrode () is p, the width of one of electrode fingers which form the comb-type electrode () is pand the width between the electrode fingers is pthen each parameter is set so that the following expressions are satisfied, L&#x2266;pand L&#x2267;p(herein, the correlations of L&#x2248;p, ppp and LLL are satisfied).

Electronic part with a comb electrode and protective film and electronic equipment including same

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

A piezoelectric vibrator which uses lithium tantalate as a piezoelectric material and of which main vibration is thickness shear vibration. The thickness direction of the vibrator forms angle of 0&#xb0;&#xb1;5&#xb0; to the X-axis of a single crystal. The longitudinal direction of vibrator lies, with the X-axis used as a rotation axis, in direction n +57&#xb0;&#xb1;2&#xb0; clockwise from the Y-axis of the single crystal. A ratio L/H of the length L of the vibrator to the thickness H is not less than 15. A ratio Le/H of the length Le of the exciting electrode to the thickness H of the vibrator element portion is 3&#x2013;6. Accordingly, a vibrator having improved temperature characteristics and a large Q is realized.

Piezoelectric vibrator ladder-type filter using piezoeletric vibrator and double-mode piezolectric filter

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

Growing community of inventors

Osaka, Japan

Tetsuo Kawasaki