SURFACE ACOUSTIC WAVE TRANSDUCER

摘要

A surface acoustic wave transducer having a piezoelectric thin film, interdigital electrodes disposed on one side surface of said piezoelectric thin film and an apodized counter electrode disposed on the opposite-side surface of said piezoelectric thin film. The outline of the apodized counter electrode is composed of parallel edges parallel to fingers of the interdigital electrode and perpendicular edges perpendicular to the fingers. The parallel edges are positioned in gaps between the fingers, so as not to lie over the fingers. Such structure remarkably reduces the deviation of characteristics of the transducer due to the incomplete alignment of the counter electrode with the interdigital electrode.