| 摘要 |
<p>A surface acoustic wave device taking advantage of the Rayleigh wave is provided, wherein a spurious due to the SH wave does not occur easily, the electrical resistance is small, and adaptation to higher frequencies is easy. A surface acoustic wave device taking advantage of the Rayleigh wave, the device including a LiNbO 3 substrate represented by Eulerian angles of (0°±5°, ¸±5°, 0°±10°), an electrode which is disposed on the above-described LiNbO 3 substrate 2 and which includes an IDT electrode 3 primarily containing Au, a first silicon oxide film 6 disposed in a region other than the region in which the above-described electrode is disposed, the first silicon oxide film having a film thickness equal to the thickness of the above-described electrode, and a second silicon oxide film 7 disposed in such a way as to cover the above-described electrode 3 and the first silicon oxide film 6, wherein the film thickness of the above-described electrode 3 is within the range of 0.062» to 0.14», where » represents the wavelength of a surface acoustic wave, and ¸ of the above-described Eulerian angles of (0°±5°, ¸±5°, 0°±10°) is specified to be within the range satisfying the following Formula (1). Mathematical formula 1 ¸ = 31.72 - 206.92 × exp - 1 × T Au / 0.0138
where T Au : a value of Au electrode film thickness normalized with the wavelength »</p> |
