| 摘要 |
PURPOSE:To improve the frequency characteristic of a elastic wave device operated at a comparatively low frequency band, by providing a recess to a package in which a piezoelectric substrate having transmission and receiving wave electrodes is fitted. CONSTITUTION:On the surface of the piezoelectric substrate 1, an interdigital input electrode 2 and an output electrode 3 are arranged. Further, a ground plane 6 of the packaging is provided with the recess 9, and ends at the back side of the piezoelectric substrate 1 are bonded with the outer circumferential senction of the recess 9 and a bonding layer 5. Moreover, the construction is so designed that the main signal propagating path at the back side is not restricted. Through the device like this, the frequency characteristic of the elastic wave device operated at a comparatively low frequency band, e.g., <=30MHz, is improved. |
