PIEZOELECTRIC MICRO SPEAKER WITH A WEIGHT ATTACHED TO A VIBRATION MEMBRANE AND A METHOD OF MANUFACTURING THE SAME, CAPABLE OF INCREASING SOUND PRESSURE IN A LOW FREQUENCY BAND BY LOWERING A RESONANT FREQUENCY OF THE VIBRATION MEMBRANE

摘要

PURPOSE: A piezoelectric micro speaker with a weight attached to a vibration membrane and a method of manufacturing the same are provided to attach a weight to a central part of a vibration membrane, thereby increasing the entire weight of the vibration membrane.;CONSTITUTION: A substrate(210) has a cavity penetrated in a thickness direction. A diaphragm(220) is formed on the substrate to cover the cavity. The diaphragm comprises a vibration membrane formed on an area corresponding to the cavity. A piezoelectric driving unit(230) is formed on the vibration membrane to vibrate the vibration membrane. A weight(240) is arranged inside the cavity. The weight is attached to the central part of the vibration membrane. The weight has a pillar shape. The center of gravity of the weight is located on the central line of the cavity.;COPYRIGHT KIPO 2011