Alps Electric Co., Ltd.

Takuo Kudo

Takashi Sato

Satoshi Waga

Kyosuke Ozaki

Takeshi Ikeda

Yutaka Matsuo

Haruhiko Fujimoto

Kazuaki Kaneko

Toshihiro Meguro

In an SAW filter on one side of a piezoelectric substrate are formed a pattern portion constituted by a conductor and provided on the outer circumferential portion of the surface acoustic wave device, and a conductor removing portion formed between the surface acoustic wave device and the pattern portion. The shape of the surface acoustic wave device is formed by the conductor removing portion and the surface acoustic wave device remains non-conductive with the pattern by the conductor removing portion.

SAW filter and method of manufacturing the same

According to the method of manufacturing a surface acoustic wave device of the invention, since a conductor layer is formed on electrode sections in a state where the entire regions of inter digital transducer and reflectors are covered with an insulating film, the inter digital transducer and the reflectors are protected by the insulating film during formation of the conductor layer. As a result, it is possible to obtain a highly efficient surface acoustic wave device with no sticking of foreign matters to the inter digital transducer and the reflectors.

Method of manufacturing a surface acoustic wave device

A surface acoustic wave device includes a piezoelectric substrate and an electrode section, disposed on the piezoelectric substrate, having a thin-film structure. The electrode section includes interdigital electrodes and junction electrodes connected to the interdigital electrodes. The interdigital electrodes each include corresponding first base layers containing Ta and Cu layers or Cu&#x2014;M alloy layers each disposed on the corresponding first base layers, wherein M represents one or more elements selected from the group consisting of Ag, Sn, and C.

Surface acoustic wave device having high dielectric strength and process for manufacturing the same

IDT electrodes are formed by a Cu alloy. When the wavelength of a SAW propagating in the direction of the X axis of a piezoelectric substrate is indicated by &#x3bb;, and when the thickness of the IDT electrodes is indicated by H, the standardized thickness H/&#x3bb; of the IDT electrodes ranges from 0.045 to 0.070, and the piezoelectric substrate is a rotated Y-cut LiTaOsubstrate whose rotational cut angle &#x3b8; from the Y axis to the Z axis around the X axis ranges from 52.0&#xb0; to 58.0&#xb0;. With this arrangement, the reflection coefficient S11 becomes 0.88 or higher.

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Fukushima-ken, Japan

Takuo Kudo