Miniature silicon condenser microphone
A silicon condenser microphone package includes a transducer unit, a substrate, and a cover. The substrate includes an upper surface transducer unit is attached to the upper surface of the substrate and overlaps at least a portion of the recess wherein a back volume of the transducer unit is formed between the transducer unit and the substrate. The cover is placed over the transducer unit and either the cover or the substrate includes an aperture.
1. A package for containing a transducer comprising:
a substrate including a surface and an aperture formed therein, the transducer attached to the surface of the substrate adjacent the aperture;
a cover secured to the substrate defining a volume, the transducer unit being disposed within the volume; and
a sealing ring being formed on a surface of the substrate opposite the volume, the sealing ring surrounding the aperture formed in the substrate.
2. The package of claim 1 , wherein the transducer is attached to the substrate completely covering the aperture.
3. The package of claim 1 , wherein the transducer is attached to the substrate partially covering the aperture.
4. The package of claim 1 , wherein the transducer is attached to the substrate leaving the aperture uncovered.
5. The package of claim 1 , the cover being formed with an aperture coupled to the volume, a layer being disposed over one or both of the apertures formed on the substrate and the cover.
6. The package of claim 5 , wherein the layer has acoustic properties.
7. The package of claim 5 , wherein the layer forms an environmental protective barrier.
8. The package of claim 1 , the package being secured to a substrate of a device, the sealing ring providing a seal between the aperture formed in the substrate and an aperture formed in the substrate of the device.
9. The package of claim 1 , a plurality of terminal pads being formed on a surface of the substrate opposite the volume, the terminal pads for providing an electrical connection between the transducer within the volume and an exterior of the package.
10. The package of claim 1 , a metalized region being formed on a surface of the substrate opposite the volume, the metalized region being disposed adjacent the aperture formed in the substrate.
11. The package of claim 1 , the cover including a conductive portion, the conductive portion forming a shield against electromagnetic interference.
12. The package of claim 11 , the conductive portion comprising a conductive layer formed in the cover.
13. The package of claim 1 , the substrate including a conductive portion, the conductive portion forming a shield against electromagnetic interference.
14. The package of claim 13 , the conductive portion comprising a conductive layer formed in the substrate.
15. The package of claim 1 , the cover including a first conductive portion, the substrate including a second conductive portion, the first conductive portion and the second conductive portion being electrically coupled, the first conductive portion and the second conductive portion forming a shield against electromagnetic interference.
16. The package of claim 15 , the first conductive portion comprising a conductive layer formed in the cover and the second conductive portion comprising a conductive layer formed in the substrate.
17. The package of claim 1 , the cover being acoustically sealed to the substrate.
18. The package of claim 1 , the substrate comprising a printed circuit board.
19. The package of claim 1 , an environmental barrier being disposed within the aperture formed in the substrate and in the aperture optionally formed in the cover, if present.
20. The package of claim 19 , the environmental barrier comprising sintered metal.
21. The package of claim 1 ,the volume comprising a back volume for the transducer.