Acoustic wave device

An acoustic wave device comprising:

• a support including a support substrate;
• a piezoelectric layer on the support;
• a functional electrode at the piezoelectric layer;
• a support frame on the piezoelectric layer and surrounding the functional electrode in a plan view in a stacking direction of the support and the piezoelectric layer;
• and
• a lid covering an opening of the support frame;
• wherein
• the support includes a first cavity at a position overlapping at least a portion of the functional electrode in the plan view in the stacking direction of the support and the piezoelectric layer;
• a second cavity defined by the piezoelectric layer, the support frame, and the lid is provided between the piezoelectric layer and the lid;
• the piezoelectric layer includes a through hole communicating with the first cavity and the second cavity;
• and
• the first cavity and the second cavity are under vacuum.