Patent ID: 8520868

Claim:
A piezoelectric micro speaker comprising: a device plate comprising a diaphragm, a piezoelectric actuator that vibrates the diaphragm, and a front cavity disposed in front of the diaphragm; a front plate which is disposed on a front surface of the device plate, the front plate comprising a radiation hole connected to the front cavity; and a rear plate which is disposed on a rear surface of the device plate, the rear plate comprising: a rear cavity which is formed in a surface of the rear plate facing the piezoelectric actuator, a bent hole which is connected to the rear cavity, a sound absorption layer which is disposed on an inner surface of the rear cavity and absorbs sound radiated backward from the diaphragm, and a wiring layer formed on the surface of the rear plate facing the piezoelectric actuator, wherein the sound absorption layer covers at least a portion of the wiring layer disposed in the rear cavity of the rear plate.