1. A subminiature condenser microphone with silicon nitride membrane and silicon backplate;Hohm;J. Acoust. Soc. Am.,1989
2. A silicon subminiature electric microphone;Sprenkels,1988
3. A silicon condenser microphone with a silicon nitride diaphragm and back-plate;Scheeper;MME'92, 3rd European Workshop Micromachining, Micromechanics and Microsystems,1992
4. Piezoelecktrische Sensoren auf Siliziumbasis für akustische Anwendungen;Franz,1988