Matsushita Electric Industrial Co., Ltd.

Panasonic Intellectual Property Management Co., Ltd.

Panasonic Corporation

Skyworks Filter Solutions Japan Co., Ltd.

Shigeru Tsuzuki

Hiroyuki Nakamura

Toru Yamada

Kazunori Nishimura

Ken Matsunami

Tsutomu Igaki

Keiji Onishi

Akio Tsunekawa

Masahiro Takada

Tomohiro Iwasaki

Kozo Murakami

Kunihiro Fujii

Satoshi Matsuo

Narihiro Mita

Takafumi Koga

Toshio Ishizaki

Tomoya Komatsu

Tetsuo Kawasaki

Shinobu Nakaya

Kazuki Nishimura

An acoustic wave element includes a piezoelectric substrate, an excitation electrode configured to excite and output a main acoustic wave on the piezoelectric substrate, a receiving electrode configured to receive the main acoustic wave, a propagation path configured to allow the main acoustic wave to propagate along the piezoelectric substrate between the excitation electrode and the receiving electrode, and a sensing portion configured to react to an object substance. The propagation path is configured to allow the main acoustic wave to pass plural times through the sensing portion along the propagation path. This acoustic wave element has high sensitivity to the object substance.

Elastic wave element and elastic wave sensor using same

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

A surface acoustic wave filter element has

Surface acoustic wave filter element, surface acoustic wave filter and communication device using the same

In a SAW device containing two or more longitudinal mode coupling type SAW elements connected in parallel, each SAW element includes at least three comb shaped electrode pairs and a reflector electrode provided at both sides of the comb shaped electrodes. One part of respective comb shaped electrode pairs forming IDT electrodes is connected together in common by a ground connection electrode and connected with a ground pad. This configuration enables the number of connection pads to be minimized, thus providing a SAW device that is small in size and superior in filter characteristics.

Surface acoustic wave device

A balanced type filter includes at least one balanced type terminal. At least one predetermined reactance element is connected between the balanced type terminal and another terminal. A parallel resonance circuit is formed by parasitic components existing between the balanced type terminal and the other terminal, and the reactance element. The other terminal is of balanced type or unbalanced type.

Surface acoustic wave filter, balanced type filter and communication device

A longitudinal mode type surface acoustic wave filter comprising a first IDT electrode, second and third IDT electrodes, and first and second reflector electrodes are formed on a piezoelectric substrate. The upper electrode of the first IDT electrode is connected to one of balanced type terminals, and the lower electrode of the first IDT electrode is connected to the other balanced type terminal. Also, the lower electrode of the second IDT electrode is connected to an unbalanced type terminal, and the lower electrode is grounded. The lower electrode of the third IDT electrode is connected to the unbalanced type terminal, and the upper electrode is grounded.

A method of manufacture of a surface acoustic wave device which includes a step of applying a photosensitive film resist on a substrate and forming a photosensitive film resist layer over at least a portion of a surface of the substrate; a step of forming acoustic absorbers only at the two sides orthogonal to the direction of the surface acoustic wave transmission; a step of placing in a package a surface acoustic wave element obtained by cutting and dividing the substrate and electrically connecting a connection electrode of the surface acoustic wave element with an external terminal of the package; and a step of sealing an opening of the package with a lid, wherein the main surface of the acoustic absorbers is formed parallel to the surface of the substrate.

Method of manufacturing a surface acoustic wave device

Surface acoustic wave filter and communications apparatus using the same

Surface acoustic wave filter and communication apparatus with the same

A SAW element ( ) is formed of a piezoelectric substrate ( ), on which are provided IDT electrodes ( ), connection electrodes ( ), underlying metal layers ( ), and acoustic materials ( ) placed on the underlying metal layers ( ) and having surfaces parallel to the main surface of the piezoelectric substrate ( ). The SAW element is mounted in a package ( ), which is provided with external terminals ( ) connected with the connection electrodes ( ), and the package is hermetically sealed with a lid ( ) to form a SAW device. When such a SAW element ( ) is mounted faceup in a package ( ) using a vacuum chuck ( ), its piezoelectric substrate ( ) can be protected against damage. When a SAW element ( ) provided with bumps ( ) on its connection electrodes ( ) is mounted facedown in a package ( ), the failure of electrical connections can be prevented.

Surface acoustic wave device and method of manufacture thereof

A saw device comprises input/output interdigital transducer (IDT) electrodes( ) provided on piezoelectric substrates ( ), a first reflector electrode ( ) following the input IDT electrode ( ), and a second reflector electrode ( ) preceding the output IDT electrode ( ). The device satisfies the following inequality ( ) to provide preferable characteristics in a pass band: 2(&thgr;&minus;5)&lE;tan (D/L)&lE;2(&thgr;&plus;5) where &thgr;: the inclination (in degree, except zero) of the first or second reflector electrode of the input and output IDT electrodes with respect to a plane perpendicular to the direction in which surface acoustic waves travel. D: the pitch (in micron) of the input and output IDT electrodes in the direction in which surface acoustic waves travel. L: the pitch (in micron) of the first and second reflector electrodes.

SAW device with inclined reflectors and communication device using SAW device

A SAW filter comprising a piezoelectric substrate and at least two filter tracks formed on the substrate, each having at least two IDT electrodes for input and output. The two filter tracks have substantially the same phase within a pass band, while it is substantially inverse-phased outside the pass band. For realizing the above-described conditions, input IDT electrode of one filter track is connected in parallel with input IDT electrode of the other filter track, while output IDT electrode of one filter track is connected in parallel with output IDT electrode of the other filter track. Furthermore, frequency values of said two filter tracks substantially coincide at a point dB lower from the peak transfer function value. Thus the above-configured SAW filter of the present invention is smaller in the overall size and offers a broad pass band and a steep attenuation characteristic.

Surface acoustic wave filter

A surface acoustic wave (SAW) filter is disclosed which comprises a piezoelectric substrate and at least two Interdigital Transducers (IDTs) having four fingered electrodes in a region corresponding to one-wavelength of SAW excited on the piezoelectric substrate. At least one IDT is formed of at least one pair of fingered electrodes having different electrode widths. By provision of the pair of fingered electrodes being different in electrode width, the IDT can be given unidirectionality. Thus, a SAW filter producing a low insertion loss and having good amplitude and phase characteristics in the pass-band can be realized. Further, by using such SAW filter, a high-performance and low-cost communication apparatus, such as a CDMA-system mobile telephone, can be realized.

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Neyagawa, Japan

Shigeru Tsuzuki