Capacitive MEMS microphone and electronic apparatus
The present invention discloses a capacitive MEMS microphone and an electronic apparatus. The capacitive MEMS microphone comprises: a diaphragm; and a substrate, wherein a cavity is formed between the diaphragm and the substrate, and the cavity is filed with an elastic body. According to an embodiment of this invention, an elastic body is adopted in a capacitive MEMS microphone to replace the air gap of the prior art such that the SNR of the microphone is increased.
1. A capacitive MEMS microphone, comprising:
a diaphragm; and
a substrate,
wherein a cavity is formed between the diaphragm and the substrate, and the cavity is filled with a solid elastic body that is spaced by a gap from side walls of the cavity.
2. The capacitive MEMS microphone according to claim 1 , wherein a dielectric spacer is provided on the substrate, the diaphragm is provided on dielectric spacer, and the cavity is sealed by the diaphragm, the dielectric spacer and the substrate.
3. The capacitive MEMS microphone according to claim 1 , wherein the solid elastic body is at least one of elastomer and gel.
4. The capacitive MEMS microphone according to claim 1 , wherein the solid elastic body has an elastic modulus in a range of 1 kPa-5 MPa.
5. The capacitive MEMS microphone according to claim 1 , wherein a top electrode is mounted on the diaphragm and a bottom electrode is mounted on the substrate.
6. The capacitive MEMS microphone according to claim 5 , wherein the bias voltage for the capacitive MEMS microphone is 1-300V.
7. An electronic apparatus, comprising a capacitive MEMS microphone according to claim 1 .
8. An electronic apparatus, comprising a capacitive MEMS microphone according to claim 2 .