| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a surface acoustic wave resonator capable of realizing satisfactory frequency temperature characteristics. <P>SOLUTION: There are provided: an IDT 12 which is provided in a principal surface of a crystal substrate 30 which is made to have θ and ψ in a range where a secondary temperature coefficient in the case of changing ϕ in a range of -60° to +60° becomes satisfactory at an Euler's angle (ϕ, θ, ψ), and which is made up of comb tooth-shaped electrodes 14a and 14b which connect, by a bus bar 16, base end parts of a plurality of electrode fingers 18 which excite a surface acoustic wave of a stop band upper end mode; and groove 32 between the electrode fingers made by recessing the substrate located between the electrode fingers which constitute the IDT. In the case where a depth of the groove between said electrode fingers is G and a wavelength is λ, a relationship of 0.02λ≤G≤0.04λ is established, and a line occupancy ratio η that is a ratio between an electrode finger width of the IDT and a width between the electrode fingers is set to 0.49≤η≤0.70. <P>COPYRIGHT: (C)2012,JPO&INPIT |
