Condenser microphone

1. A condenser microphone comprising:

a substrate having a through cavity;

a supporting member connected to the substrate and located in the cavity, the supporting member defining a first surface away from the substrate, a second surface opposite to the first surface, and an opening extending from the first surface to the second surface, the supporting member further having a periphery portion and a plurality of stationary electrodes extending from the periphery portion toward a center of the supporting member, each of the stationary electrodes having a first top surface, a first bottom surface opposite to the first top surface and a first thickness;

a diaphragm, located in the opening, defining a third surface away from the supporting member, a fourth surface opposite to the third surface and facing to the substrate, the diaphragm having a vibrating member and sustaining members connected to the vibrating member, the vibrating member defining a plurality of movable electrodes protruding from a periphery of the vibrating member, each movable electrode having a second bottom surface facing to the substrate, a second top surface opposite to the second bottom surface and a second thickness; wherein

each of the movable electrodes is located between two adjacent stationary electrodes, and each of the stationary electrodes is located between two adjacent movable electrodes.

2. The condenser microphone as described in claim 1 , wherein the substrate has at least one groove for receiving the sustaining members of the diaphragm, and the supporting member has a third gap corresponding to the groove.

3. The condenser microphone as described in claim 1 , wherein the first thickness of the stationary electrode is equal to the second thickness of the movable electrode.

4. The condenser microphone as described in claim 1 , wherein the first top surface and the second top surface are co-planar to each other.

5. The condenser microphone as described in claim 1 , wherein the first top surface, the second top surface, the first surface and the third surface are co-planar to each other.

6. The condenser microphone as described in claim 1 , wherein the sustaining members include a plurality of cantilevers protruding from the periphery of the diaphragm along a direction through a center of the diaphragm.

7. The condenser microphone as described in claim 6 , wherein the sustaining members include four cantilevers.

8. The condenser microphone as described in claim 1 , wherein the substrate defines a sidestep, the supporting member sits on the sidestep and faces the through cavity.

9. A condenser microphone, comprising:

a substrate;

a supporting member sitting on the substrate and having a plurality of first electrodes, every two adjacent first electrodes defining a first gap therebetween, the supporting member further defining a first surface, a second surface opposite to the first surface and an opening extending from the first surface to the second surface;

a diaphragm isolated from the supporting member and located in the opening, and having a plurality of second electrodes, every two adjacent second electrodes defining a second gap therebetween; wherein

each of the first electrodes is located in the second gap, and each of the second electrodes is located in the first gap.

10. The condenser microphone as described in claim 9 , wherein the substrate has a plurality of grooves for receiving the diaphragm and the supporting member defines a plurality of third gaps, each of the third gaps receiving one groove, the surface of the plurality of grooves is insulated.

11. The condenser microphone as described in claim 9 , wherein the substrate defines a sidestep and a cavity, the supporting member sits on the sidestep and faces the cavity.