Acoustic wave device and acoustic wave filter device

Abstract

An acoustic wave device includes a piezoelectric layer including a first main surface and a second main surface facing the first main surface in a first direction, an IDT electrode on at least one of the first main surface and the second main surface of the piezoelectric layer and including electrode fingers arranged in an arrangement direction, a reflector adjacent to the IDT electrode in the arrangement direction of the electrode fingers, a support that faces the second main surface of the piezoelectric layer and includes an acoustic reflection portion on a side of the second main surface of the piezoelectric layer, and a load film provided in a region overlapping with the reflector in a plan view from the first direction. When a thickness of the piezoelectric layer is d and a distance between centers of the adjacent electrode fingers is p, d/p is about 0.5 or less.

Dependencies are inferred from the claim text.