Acoustic wave device

An acoustic wave device comprising:

• a first substrate including a terminal located on a lower surface thereof and having a substantially rectangular planar shape;
• at least one second substrate including an acoustic wave element located on a lower surface thereof and mounted on the first substrate so that the acoustic wave element faces an upper surface of the first substrate across an air gap;
• a plurality of first bumps located between the upper surface of the first substrate and the lower surface of the at least one second substrate, located between a first side of the first substrate and the acoustic wave element in a direction perpendicular to the first side in plan view, and not electrically connected to at least one of the acoustic wave element and the terminal;
• a plurality of second bumps located between the upper surface of the first substrate and the lower surface of the at least one second substrate, located between a second side of the first substrate, which is opposite to the first side, and the acoustic wave element in the direction perpendicular to the first side in plan view, and not electrically connected to at least one of the acoustic wave element and the terminal;
• and
• a plurality of third bumps located between the upper surface of the first substrate and the lower surface of the at least one second substrate, located only in a region that is located closer to the second side than the plurality of first bumps are and closer to the first side than the plurality of second bumps are, and electrically connecting the acoustic wave element and the terminal,
• wherein the first side and the second side are shorter sides of the rectangular planar shape of the first substrate.