Abstract
The application of plasma-enhanced chemical vapour deposited (PECVD) silicon nitride as a diaphragm material for condenser microphones has been investigated. By means of adjusting the SiH4/NH3 gas-flow composition, silicon-rich silicon nitride films have been obtained with a relatively low tensile stress. Aluminium can be etched selectively with respect to the silicon nitride films. Using aluminium as a sacrificial layer, 300 × 300 μm silicon nitride diaphragms have been made. Admittance measurements on silicon nitride capacitances have shown that the insulating properties are sufficiently good for application as a microphone diaphragm.
Original language | English |
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Pages (from-to) | 79-84 |
Number of pages | 6 |
Journal | Sensors and Actuators B: Chemical |
Volume | 4 |
Issue number | 1-2 |
DOIs | |
Publication status | Published - 1991 |