MEMS packaging

Patent metadata

Field	Value
Publication number	US-10735868-B2
Application number	US-201816179237-A
Country	US
Kind code	B2
Filing date	Nov 2, 2018
Priority date	Nov 17, 2017
Publication date	Aug 4, 2020
Grant date	Aug 4, 2020

Abstract

A package for a MEMS device, the package comprising a MEMS transducer within a chamber of the package; and a package substrate, wherein an upper surface of the package substrate defines at least part of a surface of the chamber; wherein the package substrate comprises a plurality of metal layers, the package substrate further comprising at least a part of a filter circuit for filtering RF signals, wherein a first metal layer is provided in a first plane of the substrate and wherein a resistor of the filter circuit is provided in a plane below the first plane.

First claim

The invention claimed is:

1. A package for a MEMS device, the package comprising:
a MEMS transducer within a chamber of the package; and
a package substrate, wherein an upper surface of the package substrate defines at least part of a surface of the chamber; wherein
the package substrate comprises a plurality of metal layers, the package substrate further comprising at least a part of a filter circuit provided to filter RF signals, wherein the filter circuit comprises a resistor, a first capacitor and a second capacitor, and wherein each capacitor is electrically connected between a node of the filter circuit and a ground terminal; and
wherein a first metal layer is provided in a first plane of the substrate and wherein the resistor of the filter circuit is provided in a plane below the first plane.

2. A package for a MEMS device as claimed in claim 1 , wherein the resistor is formed by a second metal layer.

3. A package for a MEMS device as claimed in claim 2 , wherein the resistor is formed by patterning the second metal layer.

4. A package for a MEMS device as claimed in claim 1 , wherein the first capacitor is electrically connected between an input of the filter circuit and the resistor, and the second capacitor is electrically connected between the resistor and an output of the filter circuit.

5. A package for a MEMS device as claimed in claim 1 , wherein an inductor is connected in parallel with the resistor.

6. A package for a MEMS device as claimed in claim 5 , wherein the inductor is positioned at least partly externally to the package.

7. A package for a MEMS device as claimed in claim 5 , wherein the inductor is positioned within the exterior of the package.

8. A package for a MEMS device as claimed in claim 5 wherein the characteristics of the inductor, resistor, first capacitor and second capacitor are selected so that the transition frequency of the resistor-inductor circuit lies above the audible frequency range and below a radio frequency of interest.

9. A package for a MEMS device as claimed in claim 8 , wherein the radio frequency of interest is 850 MHz, 900 MHz, 1800 MHz or 1900 MHz.

10. A package for a MEMS device as claimed in claim 8 , wherein the audible frequency range is between 20 Hz and 20 kHz.

11. A package for a MEMS device as claimed in claim 1 , wherein the filter circuit is provided at least partly within the package substrate.

12. A package for a MEMS device as claimed in claim 1 , wherein the chamber of the package is enclosed.

13. A package for a MEMS device as claimed in claim 1 wherein said MEMS transducer comprises a microphone.

14. An electronic device comprising a package for a MEMS device as claimed in claim 1 .

15. An electronic device as claimed in claim 14 wherein said device is at least one of: a portable device; a battery powered device; an audio device; a computing device; a communications device; a personal media player; a mobile telephone; a games device; and a voice controlled device.

Assignees

• Cirrus Logic Int Semiconductor Ltd
• Cirrus Logic Inc

Inventors

• Achehboune Rkia
• Drogoudis Dimitris
• Brioschi Roberto
• KHENKIN Aleksey Sergeyevich
• Patten David

Classifications

• B81B7/0064

  for protecting against electromagnetic or electrostatic interferences · CPC title

• H04R19/04 Primary

  Microphones (H04R19/01 takes precedence) · CPC title

• H03H9/2426

  in combination with other electronic elements · CPC title

• B81B2207/012

  the micromechanical device and the control or processing electronics being separate parts in the same package · CPC title

• H04R19/005

  using semiconductor materials · CPC title