MANUFACTURING METHOD FOR SURFACE ACOUSTIC WAVE FILTER, SURFACE ACOUSTIC WAVE FILTER, AND COMMUNICATIONS EQUIPMENT

摘要

PROBLEM TO BE SOLVED: To design a flexible surface acoustic wave filter on an NSPUDT substrate where the excitation of a surface acoustic wave becomes unidirectional because of the anisotropy of crystal. SOLUTION: This surface acoustic wave filter 105 has a piezoelectric substrate 101 having NSPUDT characteristics, and one transmission-side interdigital transducer(IDT) electrode 103, which is provided on the piezoelectric substrate and sends the surface acoustic wave and one reception-side IDT electrode 104, which receives the surface acoustic wave, and the directivity of the surface acoustic wave is set by setting the width of the electrode fingers of the transmission-side IDT electrode 103.