Implantable microphone for an implantable hearing prothesis

1. An implantable microphone, comprising:

a housing having a diaphragm chamber formed therein, and an aperture extending from the exterior surface of the housing to the chamber;

a diaphragm disposed on the exterior of the housing so as to seal the aperture, and configured to vibrate in response to sound signals;

a sensor positioned adjacent an end of the chamber opposing the diaphragm, and configured to detect vibration of the diaphragm, and to generate electrical signals based thereon; and

a stiffening material substantially filling the regions of the housing external to the sensor and the diaphragm chamber such that air gaps within the filled regions of the housing are substantially eliminated,

wherein the stiffening material has an elastic modulus that enables the housing to substantially resist deformation thereof in response to body-noise.

2. The implantable microphone of claim 1 , wherein the stiffening material has a density such that the microphone has a mass that substantially prevents movement thereof in response to body-noise.

3. The implantable microphone of claim 1 , further comprising:

an isolation member disposed about the sensor configured to mechanically isolate the sensor from the stiffening material.

4. The implantable microphone of claim 1 , wherein the stiffening material comprises a biocompatible epoxy.

5. The implantable microphone of claim 1 , wherein the stiffening material comprises a thermoset polymer.

6. The implantable microphone of claim 1 , wherein the stiffening material comprises a thermoplastic polymer.

7. The implantable microphone of claim 1 , wherein the stiffening material is selected from the group comprising: vulcanized rubber, synthetic rubber, silicone rubber and natural rubber.

8. The implantable microphone of claim 1 , wherein the sensor comprises a capacitive plate which detects vibration of the diaphragm.

9. The implantable microphone of claim 1 , wherein the sensor comprises a pressure sensitive transducer to detect pressure changes in the diaphragm chamber.

10. The implantable microphone of claim 3 , wherein the isolation member is formed of silicone.

11. The implantable microphone of claim 1 , wherein the housing is formed from a solid piece of biocompatible material to receive the sensor element and to form the diaphragm chamber.

12. The implantable microphone of claim 1 , wherein the housing is shaped to fit closely to the sensor.

13. A method of manufacturing an implantable microphone, comprising:

providing a housing having a diaphragm chamber formed therein, and an aperture extending from the exterior surface of the housing to the chamber;

positioning a sensor in the housing so as to be adjacent an end of the diaphragm chamber opposing the diaphragm; and

substantially filling the housing with a stiffening material such that air gaps within the filled regions of the housing are substantially eliminated, wherein the stiffening material has an elastic modulus that enables the housing to substantially resist deformation thereof in response to body-noise.

14. The method of claim 13 , wherein substantially filling the housing with the stiffening material comprises:

filling the housing with a stiffening material having a density that enables the microphone to resist movement in response to body-noise.

15. The method of claim 13 , wherein substantially filling the housing with the stiffening material comprises:

introducing the stiffening material in a liquid form; and

curing the liquid stiffening material.

16. The method of claim 13 , further comprising:

positioning an isolation member about the sensor prior to substantially filling the housing with the stiffening material.

17. The method of claim 13 , wherein providing the housing having a diaphragm chamber, comprises:

forming the housing from a solid piece of biocompatible material so that the housing closely fits the sensor.

18. An implantable microphone, comprising:

a housing having a diaphragm chamber formed therein, and an aperture extending from the exterior surface of the housing to the chamber;

a diaphragm disposed on the exterior of the housing so as to seal the aperture, and configured to vibrate in response to sound signals;

a sensor positioned adjacent an end of the chamber opposing the diaphragm, and configured to detect vibration of the diaphragm, and to generate electrical signals based thereon; and

a stiffening material substantially filling the regions of the housing external to the sensor and the diaphragm chamber such that air gaps within the filled regions of the housing are substantially eliminated,

wherein the stiffening material has a density such that the microphone has a mass that substantially prevents movement thereof in response to body-noise.

19. The implantable microphone of claim 18 , wherein the stiffening material has an elastic modulus that enables the housing to substantially resist deformation thereof in response to body-noise.

20. The microphone of claim 18 , further comprising:

an isolation member disposed about the sensor configured to mechanically isolate the sensor from the stiffening material.

21. The microphone of claim 18 , wherein the implantable microphone is positioned in the main implantable module.

22. The microphone of claim 18 , wherein the implantable microphone is physically separate from the main implantable module.