| 摘要 |
Capacitive sound transducer of a very small construction, in particular a microphone has at least two joint semiconductor chips, which embody a membrane unit and a fixed counter-electrode structure. The acoustic active portion of the membrane unit 1 with at least one counter-electrode structure 3, which is separated from the membrane unit by means of an air gap, forms a system which is comparable to a field effect transistor. The membrane unit which is formed of a semiconducting ground material encompasses an acoustically active membrane surface (2), one side 5 of which confronts the counter-electrode structure is electrically conductive. The counter-electrode structure 3 has a semiconductive base material out of which there is machined a channel length which has been limited by a source-drain arrangement, the geometric width measurrement of which is on the order of magnitude of a tenth of the lateral measurement of the active membrane surface.
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