| US 7,518,470 B2 | ||
| Surface acoustic wave element, surface acoustic wave device and communication device including the same | ||
| Daisuke Makibuchi, Soraku-gun (Japan); Kazuhiro Otsuka, Soraku-gun (Japan); and Kiyohiro Iioka, Soraku-gun (Japan) | ||
| Assigned to Kyocera Corporation, Kyoto (Japan) | ||
| Filed on Nov. 30, 2006, as Appl. No. 11/565,505. | ||
| Claims priority of application No. 2005-346962 (JP), filed on Nov. 30, 2005. | ||
| Prior Publication US 2007/0120626 A1, May 31, 2007 | ||
| Int. Cl. H03H 9/00 (2006.01); H03H 9/205 (2006.01); H01L 41/02 (2006.01) | ||
| U.S. Cl. 333—193 [333/133; 333/195] | 17 Claims |
| 1. A surface acoustic wave element comprising:
a piezoelectric substrate; and
a plurality of IDT electrodes of an odd number not less than three, wherein the plurality of IDT electrodes are formed along
a propagation direction of surface acoustic waves propagating on the piezoelectric substrate,
wherein a first IDT electrode and a second IDT electrode are disposed on both sides of a third IDT electrode, wherein the
third IDT electrode is located at the center of the plurality of IDT electrodes, wherein the first IDT electrode is connected
to a first reference potential terminal and the second IDT electrode is connected to a second reference potential terminal,
and the first and second reference potential terminals are formed asymmetrically with respect to a virtual central axis that
passes through the center of the third IDT electrode and provided in a direction perpendicular to the propagation direction,
wherein the magnitudes of inductance components generated at the first and second reference potential terminals are not less
than 0.1 nH and not more than 0.3 nH.
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