Acoustic Assembly and Method of Manufacturing The Same

• US 20150117681A1
• Filed: 10/27/2014
• Published: 04/30/2015
• Est. Priority Date: 10/30/2013
• Status: Abandoned Application

• Current Assignee: Knowles Electronics Llc (Knowles Corporation)
• Original Assignee: Knowles Electronics Llc (Knowles Corporation)
• Inventors: Szczech, John, Watson, Joshua, Servis, Greg
• Application Number:
  US14/524,458
• Publication Number:
  US 20150117681A1
• Time in Patent Office: Days
• US Class Current: 381/174
• CPC Class Codes: B81B 2201/0257 Microphones or microspeakers
• CPC Class Codes: B81B 2207/012 the micromechanical device and the control or processing electronics being separate parts in the same package
• CPC Class Codes: B81B 2207/096 through the substrate
• CPC Class Codes: B81B 7/0061 suitable for fluid transfer from the MEMS out of the package or vice versa, e.g. transfer of liquid, gas, sound
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48137 the bodies being arranged next to each other, e.g. on a common substrate
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/15151 the die mounting substrate comprising an aperture, e.g. for underfilling, outgassing, window type wire connections
• CPC Class Codes: H01L 2924/16152 Cap comprising a cavity for hosting the device, e.g. U-shaped cap
• CPC Class Codes: H04R 1/04 Structural association of microphone with electric circuitry therefor in deaf-aid sets H04R25/00
• CPC Class Codes: H04R 19/005 using semiconductor materials
• CPC Class Codes: H04R 19/04 Microphones H04R19/01 takes precedence
• CPC Class Codes: H04R 2201/003 Mems transducers or their use of the electrostatic type H04R19/005
• CPC Class Codes: H04R 2410/00 Microphones
• CPC Class Codes: H04R 31/00 Apparatus or processes specially adapted for the manufacture of transducers or diaphragms therefor manufacture of microstructural arrangements of deformable or non-deformable structures in general B81C1/00182

Abstract

A microelectromechanical system (MEMS) microphone includes a base having a port extending there through. A MEMS die is coupled to the base, and the MEMS die includes a diaphragm and a back plate. An application specific integrated circuit (ASIC) is coupled to the base and the MEMS die. A cover is coupled to the base, and the cover includes customer pads. The customer pads on the cover are connected electrically to the ASIC, and the cover is arranged to form an air tight seal with the base and enclose the MEMS die and the ASIC. The microphone is connected to a customer board at the cover and arranged such that sound enters through the port in the base.

Claims

1. A microelectromechanical system (MEMS) microphone, comprising:

a base having a port extending there through;

a MEMS die coupled to the base, the MEMS die including a diaphragm and a back plate;

an application specific integrated circuit (ASIC) coupled to the base and the MEMS die;

a cover coupled to the base, the cover including customer pads, the customer pads on the cover being connected electrically to the ASIC, and the cover arranged to form an air tight seal with the base and enclose the MEMS die and the ASIC;

the microphone being connected to a customer board at the cover and arranged such that sound enters through the port in the base.

2. The MEMS microphone of claim 1 wherein the seal is formed with a solder, epoxy, or a combination of solder and epoxy.

3. The MEMS microphone of claim 1, wherein a back volume is formed between the base and the cover, and a front volume is formed that communicates with the opening.

4. The MEMS microphone of claim 1, wherein the port is aligned with an external gasket, the external gasket having a gasket opening extending there through.

5. The MEMS microphone of claim 1, wherein the base comprises a plurality of layers.

6. The MEMS microphone of claim 5, wherein the plurality of layers comprises one or more of a substrate layer and a copper layer.

7. The MEMS microphone of claim 6, wherein the substrate layer comprises one or more PCB layers.

8. The MEMS microphone of claim 1, wherein the customer board resides in a cellular phone, a personal computer, or a tablet.

9. A method of making a microelectromechanical system (MEMS) microphone, comprising:

attaching a MEMS die and application specific integrated circuit (ASIC) to a base;

providing a cover, the cover with customer pads disposed on the cover, the customer pads communicating electrically with the ASIC and the MEMS die;

attaching the cover to the base, the attachment effective to connect the ASIC to external components via the pads and to enclose the ASIC and MEMS die;

flipping the assembled base and cover over and attaching the cover to a customer board so that the assembled base and cover appear to be a top port device to a customer.

10. The method of claim 9 wherein the attaching the cover forms a seal between the cover and the base, the seal being formed with a solder, epoxy, or a combination of solder and epoxy.

11. The method of claim 9, wherein a back volume is formed between the base and the cover, and a front volume is formed to communicate with the opening.

12. The method of claim 9, further comprising aligning the port with an external gasket, the external gasket having an opening extending there through.

13. The method of claim 9, wherein the base comprises a plurality of layers.

14. The method of claim 13, wherein the plurality of layers comprises one or more of a substrate layer and a copper layer.

15. The method of claim 14, wherein the substrate layer comprises one or more PCB layers.

16. The method of claim 9, wherein the customer board resides in a cellular phone, a personal computer, or a tablet.

17. The method of claim 9, wherein the cover is formed with a laser direct structuring (LDS) material that has been laser activated.