摘要 |
<p>A filter device includes a piezoelectric substrate, an IDT arranged on a major surface of the piezoelectric substrate to define a surface acoustic wave resonator, a wiring electrode that is electrically connected to the IDT, and an acoustic member located on a major surface of the piezoelectric substrate near or adjacent to the IDT and that has an acoustic impedance different from that of the piezoelectric substrate. The wiring electrode that is to be disposed in the vicinity of the IDT is located on the acoustic member.</p> |