Methods of manufacture of top port multi-part surface mount MEMS microphones

Patent metadata

Field	Value
Publication number	US-9096423-B1
Application number	US-201414159742-A
Country	US
Kind code	B1
Filing date	Jan 21, 2014
Priority date	Nov 28, 2000
Publication date	Aug 4, 2015
Grant date	Aug 4, 2015

Abstract

Methods for manufacturing multiple top port, surface mount microphones, each containing a micro-electro-mechanical system (MEMS) microphone die, are disclosed. Each surface mount microphone features a substrate with metal pads for surface mounting the package to a device's printed circuit board and for making electrical connections between the microphone package and the device's circuit board. The surface mount microphones are manufactured from panels of substrates, sidewall spacers, and lids. Each MEMS microphone die is lid-mounted and acoustically coupled to the acoustic port disposed in the lid. The panels are joined together, and each individual substrate, sidewall spacer, and lid cooperate to form an acoustic chamber for its respective MEMS microphone die. The joined panels are then singulated to form individual MEMS microphones.

First claim

What is claimed is:

1. A method for manufacturing a plurality of solder reflow surface mount microelectromechanical system (MEMS) microphones, the method comprising:
providing an unsingulated panel comprised of a plurality of individual lids, wherein each lid has top and bottom surfaces and comprises at least one conductive layer, at least one non-conductive layer, and an acoustic port, wherein the conductive layer comprises the bottom surface of the lid, and wherein the bottom surface has an attachment region and an interior region, the attachment region positioned between the interior region and the edges of the lid, and completely bounding the interior region;
providing an unsingulated panel comprised of a plurality of individual sidewall spacers, wherein each sidewall spacer has top and bottom surfaces and comprises at least two conductive layers with a center layer of predefined thickness disposed between the two conductive layers, wherein one conductive layer comprises the top surface of the sidewall spacer and the other conductive layer comprises the bottom surface of the sidewall spacer, and wherein the sidewall spacer further comprises an opening having walls covered with conductive material, and the opening walls extend through the center layer to the top surface and the bottom surface;
providing an unsingulated panel comprised of a plurality of individual substrates, wherein each substrate comprises:
a base layer comprising at least one layer of non-conductive material, wherein the base layer has a planar top surface and a planar bottom surface, the top surface having an interior region and an attachment region, the attachment region disposed between the interior region and the edges of the base layer, and completely bounding the interior region;
a first plurality of metal pads disposed on the top surface of the base layer, wherein at least one pad of the first plurality of metal pads is located in the attachment region of the top surface of the base layer;
a second plurality of metal pads disposed on the bottom surface of the base layer, the second plurality of metal pads arranged to be within the edges of the base layer; and
one or more electrical pathways disposed completely within the base layer, wherein the pathways electrically couple one or more of the first plurality of metal pads on the top surface of the base layer to one or more of the second plurality of metal pads on the bottom surface of the base layer, and wherein the at least one metal pad located in the attachment region of the top surface of the base layer is electrically coupled to one or more of the second plurality of metal pads;

mounting a MEMS microphone die on the bottom surface of each individual lid in the unsingulated panel of individual lids;
attaching the unsingulated panel of substrates, the unsingulated panel of sidewall spacers and the unsingulated panel of lids to each other in a predetermined order;
wherein the bottom surface of each sidewall spacer is coupled to the attachment region of the top surface of its respective substrate such that the opening of each sidewall spacer and the interior region of the top surface of each substrate are respectively aligned, and the conductive material on the opening walls of each sidewall spacer is electrically coupled to its respective at least one metal pad located in the attachment region of each substrate;
wherein the top surface of each sidewall spacer is coupled to the attachment region of the bottom surface of its respective lid such that the opening of each sidewall spacer and the interior region of the bottom surface of each lid are respectively aligned, and the conductive layer of each lid is electrically coupled to the conductive material on the opening walls of its respective sidewall spacer; and
wherein the interior region of the top surface of each substrate, the opening walls of its respective sidewall spacer, and the interior region of the bottom surface of its respective lid, when the panels are attached, define the internal acoustic chamber for each of their respective MEMS microphone die; and

singulating the attached panels into a plurality of individual MEMS microphones, wherein each substrate, and its respective sidewall spacer and lid cooperatively form a housing that has surfaces substantially perpendicular to the bottom surface of the substrate.

2. A method for manufacturing a plurality of surface mount MEMS microphones according to claim 1 , wherein the method further comprises electrically coupling at least one passive electrical element between one of the first plurality of metal pads and one of the second plurality of metal pads.

3. A method for manufacturing a plurality of surface mount MEMS microphones according to claim 2 , wherein the method further comprises forming the at least one passive electrical element within the base layer of the substrate.

4. A method for manufacturing a plurality of surface mount MEMS microphones according to claim 2 , wherein the method further comprises providing the at least one passive electrical element within the base layer of each substrate in the unsingulated panel of substrates, and the at least one passive electrical element comprises a dielectric or resistive material that is different from the non-conductive material used in the base layer of each respective substrate.

5. A method for manufacturing a plurality of surface mount MEMS microphones according to claim 2 , wherein the at least one passive electrical element is configured to filter one or more of an input signal, an output signal, or input power.

6. A method for manufacturing a plurality of surface mount MEMS microphones according to claim 1 , wherein the method further comprises attaching the unsingulated panel of lids to the unsingulated panel of sidewall spacers with a first conductive material, and attaching the unsingulated panel of substrates to the unsingulated panel of sidewall spacers with a second conductive material.

7. A method for manufacturing a plurality of surface mount MEMS microphones according to claim 1 , wherein the housing protects the MEMS microphone die from at least one of light, electromagnetic interference, and physical damage.

8. A method for manufacturing a plurality of surface mount MEMS microphones according to claim 1 , wherein the method further comprises providing each lid in the unsingulated panel of lids a material layer that that substantially blocks environmental contaminants from entering the acoustic chamber through the acoustic port.

9. A method for manufacturing a plurality of surface mount MEMS microphones according to claim 1 , wherein the acoustic port in each lid in the unsingulated panel of lids is disposed in a position offset from the centerpoint of its respective lid.

10. A method for manufacturing a plurality of surface mount MEMS microphones according to claim 1 , wherein the center layer of the each sidewall spacer in the unsingulated panel of sidewall spacers comprises multiple layers of conductive and non-conductive material, and the conductive material on the opening walls of each sidewall spacer electrically couples the conductive layers to each other.

11. A method for manufacturing a plurality of surface mount MEMS microphones according to claim 1 , wherein the method further comprises plating the first and second pluralities of metal pads on the base layer of each substrate with a metal that is different from the metal used for the first and second pluralities of metal pads of each substrate in the panel of unsingulated substrates.

12. A method for manufacturing a plurality of surface mount MEMS microphones according to claim 1 , wherein the base layer of each

Assignees

• Knowles Electronics Llc

Inventors

• Minervini Anthony D

Classifications

• H10P54/00

  Cutting or separating of wafers, substrates or parts of devices · CPC title

• H10W76/60

  Seals · CPC title

• H10W70/692

  Ceramics or glasses · CPC title

• Y10T29/49005

  Acoustic transducer · CPC title

• H04R2225/49

  Reducing the effects of electromagnetic noise on the functioning of hearing aids, by, e.g. shielding, signal processing adaptation, selective (de)activation of electronic parts in hearing aid · CPC title