Interposer for MEMS-on-lid microphone

• US 9,307,328 B2
• Filed: 01/06/2015
• Issued: 04/05/2016
• Est. Priority Date: 01/09/2014
• Status: Active Grant

• Current Assignee: Knowles Electronics Llc (Knowles Corporation)
• Original Assignee: Knowles Electronics Llc (Knowles Corporation)
• Inventors: Szczech, John, Watson, Joshua, Servis, Gregory B.
• Primary Examiner(s): Le, Huyen D
• Application Number:
  US14/590,635
• Publication Number:
  US 20150195659A1
• Time in Patent Office: 455 Days
• Field of Search: 381/113, 381/355, 381/360, 381/369, 381/174, 381/175, 381/189, 381/191, 257/433, 257/659, 257/678, 257/684, 257/690, 438/51, 438/53, 29/254.1, 29/254.2
• US Class Current: 1/1
• 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 2224/8592 Applying permanent coating, e.g. protective coating
• 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: H04R 1/086 Protective screens, e.g. all weather or wind screens
• 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
• CPC Class Codes: H04R 23/006 using solid state devices solid state devices per se H01L

Abstract

A microphone includes an interposer, a lid, and a base. The interposer includes at least one wall portion that forms a cavity. The wall portion includes a first side and a second side that are opposite from each other. The lid is coupled to the first side of the interposer and the base is coupled to the second side of the interposer such that the lid and the base enclose the cavity. A microelectromechanical system (MEMS) device is disposed in the cavity. The interposer structurally supports one or both of the lid and the base. The interposer includes a plurality of plated regions that are configured to electrically connect the lid and the base. The plated regions are configured to at least partially be exposed and open to the cavity.

Claims

1. A microphone, the microphone comprising:

an interposer, the interposer including a first wall, a second wall, a third wall, and a fourth wall, wherein the first wall is opposite the second wall and the third wall is opposite the fourth wall, the first wall, second wall, third wall and fourth wall forming a cavity, the interposer further including a first side and a second side, the first side and the second side being opposite from each other and orthogonal to the first wall, second wall, third wall, and fourth wall, wherein the first side is plated with a first metallic material and the second side is plated with a second metallic material to provide an acoustic seal;

a lid coupled to the first side of the interposer;

a base coupled to the second side of the interposer such that the lid and the base enclose the cavity;

a microelectromechanical system (MEMS) device disposed in the cavity;

such that the interposer structurally supports one or both of the lid and the base, the interposer including a plurality of plated regions that are configured to electrically connect the lid and the base, the plated regions being configured to at least partially be exposed and open to the cavity.

2. The microphone of claim 1, further comprising an application specific integrated circuit (ASIC) disposed in the cavity.

3. The microphone of claim 1, wherein the MEMS device is coupled to the lid.

4. The microphone of claim 1, wherein the lid comprises a multi-layer FR-4 printed circuit board.

5. The microphone of claim 1, wherein the base comprises a printed circuit board at least partially constructed of an insulating material.

6. The microphone of claim 1, wherein the at least one wall includes an RF shield.

7. The microphone of claim 6, wherein the RF shield comprises a Faraday shield or Faraday pads.

8. The microphone of claim 1, wherein the at least one wall portion comprises a first wall and a second wall, and wherein the plurality of plated regions comprises a first plated region disposed at the first wall and wherein an RF shield is disposed at the second wall.

9. The microphone of claim 1, wherein a port is disposed through the lid.

10. The microphone of claim 1, wherein the first metallic material and the second metallic material are a same type of metallic material.

11. The microphone of claim 1, wherein the lid and the base are not supported by any structure other than the interposer.

12. The microphone of claim 1, wherein the first metallic material and the second metallic material form solderable rings of metallization that are sealed with solder after reflow.