MEMS microphone and method for fabricating the same

A MEMS microphone, comprising:

• a substrate including an air chamber in a central portion;
• a back-plate disposed above the substrate and including a plurality of penetration holes through which a sound wave passes;
• and
• a vibration membrane disposed between the back-plate and the substrate, forming compressive residual stress, having a base form convexly bent toward the back-plate, and configured to vibrate a sound pressure transferred through the plurality of penetration holes,
• wherein the vibration membrane comprises:
• a corrugation portion disposed within a range of the air chamber;
• and
• a bent portion located radially inside the corrugation portion, and located closer to the back-plate in comparison with a part of the vibration membrane radially outside the corrugation portion,
• wherein the base form of the vibration membrane means a form of the vibration membrane at a free state, in which no sound pressure is applied to the vibration membrane and no voltage is applied between the back-plate and the vibration membrane,
• wherein, in the base form of the vibration membrane, the vibration membrane is configured to support the bent portion toward the back-plate by the compressive residual stress of the vibration membrane.