| 摘要 |
PROBLEM TO BE SOLVED: To suppress variations in temperature characteristics to be suppressed in a SAW device, and to enable miniaturization to be suited for mass production. SOLUTION: A single type IDT 13 composed of crossed-finger electrodes 12a, 12b each having thickness H to be H/λ≤0.085 relating to wave lengthλof the SAW is to be formed on a main surface of a crystal substrate 11 composed of an in-plane rotation ST cut crystal having an Eiler angle to be indicated by (0°,θ,0°<¾Ψ¾<90°), preferably by (0°,θ,9°<¾Ψ¾<46°), more preferably by (0°,95°<θ<155°,33°<¾Ψ¾<46°). Thereby good temperature characteristics for making frequency variation widthΔfab suppressed to be equal to or lower than 25 ppm within a usage temperature range (0 to 70°C) including variations in manufacturing can be acquired by exciting in an upper bound mode of a stop band. COPYRIGHT: (C)2008,JPO&INPIT
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