Boundary acoustic wave device

摘要

A boundary acoustic wave device includes a solid layer laminated onto a single crystal substrate, electrodes provided between the single crystal substrate and the solid layer, and boundary acoustic wave elements provided on the single crystal substrate having the same cut angle, wherein the propagation direction of one of the boundary acoustic wave elements is different from that of at least one of the other boundary acoustic wave elements. A compact and high-performance boundary acoustic wave device using a boundary acoustic wave is provided by increasing the steepness of a filter band and by forming filters or resonators with different fractional bandwidths on a single substrate.