MEMS Speaker

A MEMS speaker including:

• a substrate enclosing a cavity and being provided with openings at both ends;
• a cantilever beam extending from one end of the substrate to the cavity and at least partially suspended above the cavity;
• a piezoelectric actuator fixed on a side of the cantilever beam away from the cavity;
• a polymer layer disposed on a side of the piezoelectric actuator away from the cavity and attached to the cantilever beam and the piezoelectric actuator for completely covering the cantilever beam, the piezoelectric actuator and the cavity;
• a piezoelectric composite vibration structure formed by the polymer layer, the cantilever beam and the piezoelectric actuator for generating vibration and sound;
• wherein
• the cantilever beam includes a first section fixed to the substrate, a second section extending from the first section to the cavity and suspended above the cavity, and a third section extending from the second section away from the first section, an end of the third section away from the second section being suspended;
• and
• the piezoelectric actuator is only fixed with the third section.