| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a surface wave instrument of excellent frequency temperature characteristics, a large electromechanical coupling coefficient and a small propagation loss. <P>SOLUTION: The surface wave instrument 1 is provided with: a piezoelectric substrate 2 composed of 20°-48° rotated Y plate X propagation LiTaO<SB>3</SB>; an IDT 3 formed on the piezoelectric substrate 2 and composed of tungsten, wherein a standard film thickness H/λ is in a range of 0.0025-0.06 when defining a film thickness as H and the wavelength of a surface wave as λ; and an SiO<SB>2</SB>film formed on the piezoelectric substrate 2 so as to cover the IDT 3, wherein the standard film thickness Hs/λ is in a range of 0.10-0.40. <P>COPYRIGHT: (C)2008,JPO&INPIT |
