New architecture MEMS microphone realization
Published : 8 November 2016
While MEMS microphones performances stagnate, specifications imposed by voice recongnition or noise cancellation are still not addressed.
The counter-electrode, placed in front of the membrane to realize a capacitive detection, is the main limit, by disturbing acoustic path.
Several ways are explored to remove the electrode and increase performances:
– Detection change: piezoelectricity (Vesper), piezoresistivity (CEA-Léti)
– Capacitive comb all around the membrane (Infineon)
A new architecture patented by CEA conserves capacitive detection and its avantages while removing induced noises. The thesis work is to design, produce and test a first device taking advantage of this architecture.