Condenser microphone and packaging method for the same

• US 20070057602A1
• Filed: 09/12/2006
• Published: 03/15/2007
• Est. Priority Date: 09/14/2005
• Status: Active Grant

• Current Assignee: BSE Company Limited (BSE Holdings Company Limited)
• Original Assignee: BSE Company Limited (BSE Holdings Company Limited)
• Inventors: Song, Chung
• Granted Patent: US 8,126,166 B2
• Time in Patent Office: Days
• US Class Current: 310/328
• CPC Class Codes: H01L 2924/16151 Cap comprising an aperture, e.g. for pressure control, encapsulation
• CPC Class Codes: H01L 2924/16152 Cap comprising a cavity for hosting the device, e.g. U-shaped cap
• CPC Class Codes: H04R 1/06 Arranging circuit leads; Relieving strain on circuit leads
• CPC Class Codes: H04R 19/04 Microphones H04R19/01 takes precedence
• CPC Class Codes: H04R 31/006 Interconnection of transducer parts of diaphragm and outer suspension by moulding H04R31/003

Abstract

Disclosed is a silicone based condenser microphone comprising: a metal case which includes a sound hole, a board which is mounted with a MEMS microphone chip and an ASIC chip having an electric voltage pump and a buffer IC and is formed with a connecting pattern for joining with the metal case. A fixing material for fixing the metal case to the board, and an adhesive for applying to the whole part where the metal case fixed to the board by the fixing material is joined with the board to bond the metal case to the board. Therefore, the metal case is tack-welded to the board by a laser to fix the case to the board and then the case is bonded to the board with the adhesive, thereby decreasing an inferiority ratio and strengthening a joining force and thus enhancing a mechanical firmness and highly resisting noise from the outside.

Claims

1. A silicone based condenser microphone comprising:

a metal case which includes a sound hole;

a board which is mounted with a Micro Electro Mechanical System (MEMS) microphone chip and an application specific integrated circuit (ASIC) chip having a electric voltage pump and a buffer IC and is formed with a connecting pattern for joining with the metal case;

a fixing means for fixing the metal case to the board; and

an adhesive for applying to the whole part where the metal case fixed to the board by the fixing means is joined with the board to bond the metal case to the board.

2. The silicone based condenser microphone according to claim 1, wherein the fixing means is a provisional spot welding point formed by laser welding or soldering.

3. The silicone based condenser microphone according to claim 1, wherein the adhesive is any one selected from the group of conductive epoxy, nonconductive epoxy, silver paste, silicone, urethane, acryl and cream solder.

4. The silicone based condenser microphone according to claim 1, wherein the metal case has any one of a cylindrical shape and a rectangular parallelepiped shape.

5. The silicone based condenser microphone according to claim 4, wherein an end of the metal case has a skirt shape which is formed by bending the end outwardly.

6. The silicone based condenser microphone according to claim 1, wherein the board is any one selected from the group of a printed circuit board (PCB), a ceramic board, a flexible PCB (FPCB) and a metal PCB.

7. The silicone based condenser microphone according to claim 1, wherein the metal case is made of any one selected from the group of brass, aluminum and nickel alloy.

8. The silicone based condenser microphone according to claim 1, wherein the board is formed with connecting terminals for connecting with an external circuit on a reverse side of the side which has the metal case mounted thereon.

9. The silicone based condenser microphone according to claim 1, wherein the board is formed with connecting terminals for connecting with an external circuit on the side which has the metal case mounted thereon.

12. The silicone based condenser microphone according to claim 1, wherein the fixing means is a provisional spot welding point formed by laser welding or soldering.

13. The silicone based condenser microphone according to claim 1, wherein the adhesive is any one selected from the group of conductive epoxy, nonconductive epoxy, silver paste, silicone, urethane, acryl and cream solder.

14. The silicone based condenser microphone according to claim 1, wherein the sound hole of the board is formed on the position where the MEMS chip is mounted.

10. A method for packaging a silicone based condenser microphone, the method comprising the steps of:

inputting a board which is mounted with a Micro Electro Mechanical System (MEMS) chip and an application specific integrated circuit (ASIC) chip and is formed with a connecting pattern;

inputting a metal case;

aligning the metal case on the connecting pattern of the board;

fixing the metal case to the connecting pattern of the board by provisional spot welding;

bonding the metal case to the connecting pattern where the metal case fixed to the board is joined with the board with an adhesive; and

curing the adhesive.

11. A silicone based condenser microphone comprising:

a metal case having a bottom surface which is closed;

a board which is formed with a sound hole for collecting an external sound and a sealing terminal for solder-sealing the sound hole to prevent distortion of a sound wave in the space between a main printed circuit board (PCB) and the microphone, the board being mounted with a Micro Electro Mechanical System (MEMS) microphone chip and an application specific integrated circuit (ASIC) chip having an electric voltage pump and a buffer IC, the board being formed with a connecting pattern for joining with the metal case;

a fixing means for fixing the metal case to the board; and

an adhesive for applying to a whole perimeter of the case where the metal case fixed to the board by the fixing means meets the board to bond the metal case to the board.

15. A directional silicone condenser microphone comprising:

a metal case which is formed with the first sound inlet hole for collecting the first sound;

a board which is formed with the second sound inlet hole for collecting a second sound, the board being mounted with a Micro Electro Mechanical System (MEMS) microphone chip and an application specific integrated circuit (ASIC) chip having a electric voltage pump and a buffer IC and being formed with a connecting pattern for joining with the metal case;

a phase delayer for delaying the phase of sound collected through the first sound inlet hole or the second sound inlet hole;

a fixing means for fixing the metal case to the board; and

an adhesive for applying to a whole perimeter of the case where the metal case fixed to the board by the fixing means meets the board to bond the metal case to the board.

16. The directional silicone condenser microphone according to claim 15, wherein the fixing means is a provisional spot welding point formed by laser welding or soldering.

17. The directional silicone condenser microphone according to claim 15, wherein the adhesive is any one selected from the group of conductive epoxy, nonconductive epoxy, silver paste, silicone, urethane, acryl and cream solder.

18. The directional silicone condenser microphone according to claim 15, wherein the board is formed with connecting terminals for connecting with an external circuit on a reverse side of the side where the metal case is mounted.

19. The directional silicone condenser microphone according to claim 15, wherein the board is formed with connecting terminals for connecting with an external circuit on the side where the metal case is mounted.

20. The directional silicone condenser microphone according to claim 15, wherein the phase delayer is mounted on any one of the inside of the first sound inlet hole of the metal case, the outside of the first sound inlet hole of the metal case, the inside of the second sound inlet hole of the board and the outside of the second sound inlet hole of the board.