Surface acoustic wave device

摘要

A surface acoustic wave device includes a piezoelectric substrate, an input first interdigital electrode, and an output second interdigital electrode. The input first interdigital electrode is formed on the piezoelectric substrate. The output second interdigital electrode is formed on the piezoelectric substrate to be adjacent to the first interdigital electrode. A ratio of an overlap width to an aperture width of the first interdigital electrode and a ratio of an overlap width to an aperture width of the second interdigital electrode are set to different values, so that a transverse secondary mode is suppressed with one of the first and second interdigital electrodes while a transverse quaternary mode is suppressed with the other of the first and second interdigital electrodes.