| 摘要 |
<p>An IDT electrode (4) is formed on a double-layer structure comprising a diamond crystal layer (2) and a thin AlN film (3) and a third-order Rayleigh or Sezawa wave is caused to propagate along the surface of the double-layer. Alternatively a third-order Rayleigh wave is caused to propagate along the surface of a triple-layer structure comprising a diamond crystal layer (2), a thin AlN film (3) and an SiO2 film provided therebetween. With the aforementioned structure, a SAW device exhibiting a high electromechanical coupling factor and a high phase velocity is available. The SAW device for allowing a third-order Rayleigh wave to propagate along the surface thereof is fit for use as a narrow-band timing extraction filter or a band-pass filter, for use in a microwave region of several to 20 GHz whereas the SAW device for allowing the Sezawa wave to propagate therealong is fit for use as a wide-band voltage control oscillator or a wide-band-pass filter for use in wide range of frequencies covering VHF to UHF bands.</p> |
