| 摘要 |
<p>On the top surface of a silicon substrate (32) having a hollow portion (37), a vibration electrode plate (34) which performs film vibration when receiving vibration is provided. Moreover, over the vibration electrode plate (34), a fixed electrode plate (36) through which a plurality of acoustic perforations (43) are opened in the thickness direction, arranging the vibration electrode plate (34) and the fixed electrode plate (36) opposite to each other. Surrounding the hollow part (37), between the upper surface of a silicon substrate (32) and the lower surface of the vibration electrode plate (34), a vent hole (45) is provided to allow an air gap (35) between the vibration electrode plate (34) and the fixed electrode plate (36) to communicate with the hollow part (37). In an area corresponding to the vent hole (45), an air escape portion (42) in the state of a plurality of through holes is opened in the vibration electrode plate (34).</p> |
