A miniature silicon condenser microphone with a reinforced piston type diaphragm has been developed. The microphone, with a highly sensitive diaphragm (1mm2 in area) and a highly rigid back plate has been fabricated in a single wafer process. The equivalent electrical circuit method and the finite element method (FEM) have been used to evaluate the acoustic and mechanical performance of the microsensor. A procedure to achieve a structure with optimal mechanical sensitivity has been proposed and diaphragms with different geometries have been designed and simulated with this method. Sensitivities in the range of 5 - 10 mVPa-1 can be achieved under bias voltages of 1.5 - 7 V for devices with frequency bandwidths between 10 and 50 kHz.
Piston-type condenser microphone with structured polysilicon
Colpo, Sabrina;Faes, Alessandro;Cattin, Davide;Oboe, Roberto;Giacomozzi, Flavio;Margesin, Benno
2007-01-01
Abstract
A miniature silicon condenser microphone with a reinforced piston type diaphragm has been developed. The microphone, with a highly sensitive diaphragm (1mm2 in area) and a highly rigid back plate has been fabricated in a single wafer process. The equivalent electrical circuit method and the finite element method (FEM) have been used to evaluate the acoustic and mechanical performance of the microsensor. A procedure to achieve a structure with optimal mechanical sensitivity has been proposed and diaphragms with different geometries have been designed and simulated with this method. Sensitivities in the range of 5 - 10 mVPa-1 can be achieved under bias voltages of 1.5 - 7 V for devices with frequency bandwidths between 10 and 50 kHz.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
