A mask according to an embodiment comprises: a first substrate disposed on a first base layer; a first wire disposed on the first substrate; a piezoelectric element disposed on the first wire; a second wire disposed on the piezoelectric element; a second substrate disposed on the second wire; a second base layer disposed on the second substrate; and a cavity disposed between the first base layer and the piezoelectric element, wherein the cavity is disposed in a region overlapping the piezoelectric element in a vertical direction.