| 摘要 |
<p>The present invention provides a filter device comprising: a substrate having a top surface and a bottom surface; at least one acoustic wave situated on the top surface of the substrate, wherein the bottom surface of the substrate is roughened to reduce the reflection of an acoustic wave back to the acoustic wave filter. The effect achieved by the roughening of the bottom surface of the substrate that an acoustic wave which is generated by the acoustic wave filter and reaches the bottom surface of the substrate, is basically scat acoustic wave that is actually reflected back to the acoustic wave device is reduced which, in turn, improves the performance characteristics of the acoustic wave filter.</p> |
