| 摘要 |
PURPOSE:To easily realize suppression of an undesired wave of an SH wave type surface wave (love wave, B-G wave) device, by attaching a metallic film having a speed of a transversal wave smaller than a speed of a transversal wave of a piezoelectric substrate between an acoustical absorbent and a transducer. CONSTITUTION:An electrode film 40 is attached between a transducer 20 and and an acoustical absorbent 30, which are provided on a piezoelectric substrate 10. Above all, in case of a love wave device, as for an electrode material for constituting the transducer 20, a material having a speed of a transversal wave smaller than a speed of a transversal wave of the substrate is necessary, but as a result of attaching the same electrode film 40 as this material, suppression of an undesired wave by the acoustical absorbent has proved to be effective. On the other hand, in case of a B-G wave, it is different from a wave, its electrode material is not limited essentially, and any semiconductive film can be used. |
