SURFACE ACOUSTIC WAVE DEVICE AND METHOD FOR MANUFACTURING THE SAME

摘要

A surface acoustic wave device of the present invention comprises a hard layer comprising diamond or a diamond-like carbon film, and a piezoelectric layer formed on the hard layer. It further comprises a pair of a interdigital transducer and a grounding electrode, which perform an electro-mechanical conversion, placed with the piezoelectric layer between. Then, the feature of the present invention is to form the grounding electrode of a conductive oxide. It is preferred that the conductive oxide is formed by doping an impurity into piezoelectric material of ZnO, namely. Therefore, the adhesive between the piezoelectric layer and the hard layer, and the grounding electrodes is increased, so that the yielding of device is enhanced; and further, the high electromechanical coupling coefficient can be obtained in a high frequency range.