| 摘要 |
This invention relates to a differential pressure sensor, one embodiment of which is a microphone. The differential pressure sensor comprises: a flexible membrane ( 7 ) made of conductive material, which membrane forms a first electrode of the differential pressure sensor, and a perforated plate ( 6 ) made of conductive material, which plate is essentially more rigid than said membrane ( 7 ), which plate is arranged at a distance from the membrane, and which plate forms a second electrode of the differential pressure sensor. In order to provide a differential pressure sensor with as good properties as possible, the differential pressure sensor comprises a substrate ( 4 ), a cavity ( 10 ) extending through the substrate, the walls of which cavity are formed of said substrate ( 4 ). The membrane ( 7 ) is closely connected to the walls of the cavity ( 10 ), whereby the membrane forms a dense wall in said cavity, and said perforated plate ( 6, 6' ) has been attached to the substrate with an insulating layer ( 5 ). |
