Miniature silicon condenser microphone and method for producing the same

• US 20050185812A1
• Filed: 04/22/2005
• Published: 08/25/2005
• Est. Priority Date: 11/28/2000
• Status: Active Grant

• Current Assignee: Knowles Electronics Llc (Knowles Corporation)
• Original Assignee: Knowles Electronics Llc (Knowles Corporation)
• Inventors: Minervini, Anthony D.
• Granted Patent: US 7,242,089 B2
• Time in Patent Office: Days
• US Class Current: 381/355
• CPC Class Codes: B81B 2201/0257 Microphones or microspeakers
• CPC Class Codes: B81B 7/0064 for protecting against electromagnetic or electrostatic interferences
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H04R 19/016 for microphones
• CPC Class Codes: H04R 31/006 Interconnection of transducer parts of diaphragm and outer suspension by moulding H04R31/003
• CPC Class Codes: Y10T 29/49005 Acoustic transducer
• CPC Class Codes: Y10T 29/4908 Acoustic transducer

Abstract

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.

Claims

1. A silicon condenser microphone comprising:

a transducer unit;

a substrate include a surface having a recess formed therein, the transducer unit attached to the surface of the substrate overlapping at least a portion of the recess to form a volume adjacent the transducer unit;

a cover placed over the transducer unit; and

an aperture formed in one of the cover or the substrate and acoustically coupled to the transducer unit.

2. The silicon condenser microphone of claim 1, the cover including a conductive portion, the conductive portion forming a shield against electromagnetic interference.

3. The silicon condenser microphone of claim 2, the conductive portion comprising a conductive layer formed in the cover.

4. The silicon condenser microphone of claim 2, the conductive portion comprising a lining disposed on an inner surface of the cover.

5. The silicon condenser microphone of claim 2, the conductive portion comprising a metal or metal alloy.

6. The silicon condenser microphone of claim 1, the cover comprising a multi-layer structure including a conductive layer and an insulating layer.

7. The silicon condenser microphone of claim 1, the substrate comprising a conductive portion for forming a shield against electromagnetic interference, the conductive portion of the cover and the conductive portion of the substrate being electrically coupled.

8. The silicon condenser microphone of claim 7, the conductive portion of the substrate comprising a conductive layer formed in the substrate.

9. The silicon condenser microphone of claim 1, the cover being acoustically sealed to the substrate.

10. The silicon condenser microphone of claim 1, the substrate comprising a multi-layer structure including at least one conductive layer and at least one insulating layer.

11. The silicon condenser microphone of claim 1, the substrate comprising a printed circuit board.

12. The silicon condenser microphone of claim 11, the printed circuit board including terminal pads for electrically coupling to the transducer unit.

13. The silicon condenser microphone of claim 1, the aperture being formed in the cover.

14. The silicon condenser microphone of claim 1, the aperture being formed in the substrate.

15. The silicon condenser microphone of claim 1, an environmental barrier being disposed within the aperture.

16. The silicon condenser microphone of claim 15, the environmental barrier comprising sintered metal.

17. The silicon condenser microphone of claim 1, the volume comprising a back volume for the transducer.