Fabrication of a subminiature silicon condenser microphone using the sacrificial layer technique
- 24 June 1991
- proceedings article
- Published by Institute of Electrical and Electronics Engineers (IEEE)
Abstract
The application of the sacrificial layer technique for the fabrication of a subminiature silicon condenser microphone with a plasma-enhanced chemical vapor deposited silicon nitride diaphragm has been investigated. Square diaphragms with dimensions from 0.6 to 2.6 mm and a thickness of 1 ¿m have been realized. Measurements on a microphone with a 2×2 mm diaphragm and a 1 ¿m airgap have shown that a sensitivity of 1.4 mV/Pa for low frequencies can be achieved with a low bias voltage (-2 V). The sensitivity decreases for high frequencies. This effect is probably due to the small airgap. Therefore, microphones with wider airgaps have to be developed to achieve a flat frequency response for the entire audio frequency rangKeywords
This publication has 3 references indexed in Scilit:
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- A subminiature condenser microphone with silicon nitride membrane and silicon back plateThe Journal of the Acoustical Society of America, 1989