Influence of a thin adhesion layer on the damping of surface acoustic waves

The attenuation of surface acoustic waves (SAWs) on YZ‐LiNbO3 crystals, coated with an aluminum layer of several hundred angstroms, has been measured as a function of temperature in the range from 0.3 K to room temperature. A peak in attenuation was found between 50 and 250 K dependent on layer thickness and SAW frequency. Addition of an adhesion layer with a thickness of about 15 A, placed between substrate material and metal coating, drastically lowers the attenuation at higher temperatures. In this case, the attenuation rises slowly with temperature and no peak occurs.