| 摘要 |
An acoustic sensor capable of improving the sensor S/N ratio, without impeding reduction in sensor size is provided. A back chamber (45) opens at the top and bottom to a silicon substrate (42). A thin-film diaphragm (43) which serves as a movable electrode plate is formed on the upper surface of the substrate (42) so as to cover the back chamber (45). Back plates (48) are fixed to the upper surface of the substrate (42) so as to cover the diaphragm (43) and fixed electrode plates (49) are disposed on the lower surface of the back plates (48). In addition, the diaphragm (43) is divided into a plurality of areas by a slit (47), and a plurality of capacitors (acoustic sensing sections) (60a, 60b) connected in parallel are configured by each of the plurality of divided diaphragms (43a, 43b) and the fixed electrode plates (49).
|
