发明名称 |
Surface acoustic wave device, and mobile communication device and sensor both using same |
摘要 |
In a surface acoustic wave (SAW) device, such as a SAW resonator or a SAW filter, loss is minimized and steep characteristics are improved. IDT electrodes and a reflector are provided to a piezoelectric substrate cut out at a cut-angle which allows the substrate to excite a leaky surface acoustic wave (LSAW). The IDT electrodes have a given film thickness and a given pitch "p" of finger-electrodes. A phase velocity of the SAW is reduced to slower than a phase velocity "vb"of a slow shear wave propagating on the piezoelectric substrate, and a resonance frequency "f" satisfies a relation of 2xp<=vb/f. This structure allows the use of a Rayleigh surface acoustic wave (RSAW) which does not produce propagation loss, and improving insertion-loss and steep characteristics from those of a conventional SAW device using the LSAW.
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申请公布号 |
US7109828(B2) |
申请公布日期 |
2006.09.19 |
申请号 |
US20040482442 |
申请日期 |
2004.05.04 |
申请人 |
MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD. |
发明人 |
TAKAYAMA RYOICHI;SEKI SHUNICHI;KAWASAKI TETSUO;NAKANISHI HIDEKAZU;HASEGAWA KOJI |
分类号 |
H03H9/25;H03H9/02;H03H9/145;H03H9/64 |
主分类号 |
H03H9/25 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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