Surface acoustic wave transmission device for a low frequency signal below 30 MHz

摘要

Disclosed is a surface acoustic wave transmission device comprising a piezoelectric substrate provided thereon with an input and output transducers for transmitting and receiving the surface acoustic wave, a package for accommodating the piezoelectric substrate, and an adhesion layer for fixing the bottom of the piezoelectric substrate to the ground plane of the package. The adhesion layer is made to have a thickness of lambda R/2.6 or more wherein lambda R: is the wave length of the surface acoustic wave at the main lobe of the operating frequency, so that unnecessary waves caused by bulk wave components are absorbed.