MEMS Device and Method of Manufacturing a MEMS Device

Patent metadata

Field	Value
Publication number	US-2018201504-A1
Application number	US-201815923599-A
Country	US
Kind code	A1
Filing date	Mar 16, 2018
Priority date	Oct 12, 2012
Publication date	Jul 19, 2018
Grant date	—

Abstract

A method for manufacturing a MEMS device is disclosed. Moreover a MEMS device and a module including a MEMS device are disclosed. An embodiment includes a method for manufacturing MEMS devices includes forming a MEMS stack over a first main surface of a substrate, forming a polymer layer over a second main surface of the substrate and forming a first opening in the polymer layer and the substrate such that the first opening abuts the MEMS stack.

First claim

What is claimed is:

1 . A method for manufacturing microelectromechanical systems (MEMS) devices, the method comprising:
forming a MEMS stack over a first main surface of a substrate; forming a polymer layer over a second main surface of the substrate; forming a first opening in the polymer layer and the substrate such that the first opening abuts the MEMS stack; forming a second opening in the polymer layer while forming the first opening in the polymer layer; filling the second opening with an etch stop material; and after filling the second opening with the etch stop material, etching the substrate to extend the first opening into the substrate.

2 . The method according to claim 1 , further comprising performing a release etch to form moveable components of the MEMS devices.

3 . The method according to claim 2 , performing the release etch comprising etching with HF based chemistry.

4 . The method according to claim 2 , wherein the MEMS stack comprises a sacrificial layer disposed between a backplate and a membrane, and wherein the release etch removes all of the sacrificial layer.

5 . The method according to claim 2 , wherein the MEMS stack comprises a sacrificial layer disposed between a backplate and a membrane, and wherein the release etch removes a substantial portion of the sacrificial layer leaving spacers.

6 . The method according to claim 1 , wherein the polymer layer is a negative photoresist.

7 . The method according to claim 1 , wherein the polymer layer is a positive photoresist.

8 . The method according to claim 1 , further comprising cutting the substrate to form individual MEMS devices without removing the polymer layer.

9 . The method according to claim 8 , wherein the cutting is aligned with the second opening.

10 . The method according to claim 8 , wherein the etch stop material comprises a hard mask.

11 . A method for manufacturing microelectromechanical systems (MEMS) devices, the method comprising:
forming a MEMS stack over a first main surface of a substrate; thinning the substrate to expose a second main surface; forming an etch stop layer over the second main surface of the substrate; patterning the etch stop layer to expose portions of the second main surface directly over the MEMS stack; depositing a polymer layer covering the patterned etch stop layer and the exposed second main surface; forming a first opening and a second opening in the polymer layer such that the first opening is formed directly over the MEMS stack; extending the first opening into the substrate without extending the second opening; and performing a release etch to form moveable components of the MEMS devices.

12 . The method according to claim 11 , performing the release etch comprising etching with HF based chemistry.

13 . The method according to claim 11 , wherein the MEMS stack comprises a sacrificial layer disposed between a backplate and a membrane, and wherein the release etch removes all of the sacrificial layer.

14 . The method according to claim 11 , wherein the MEMS stack comprises a sacrificial layer disposed between a backplate and a membrane, and wherein the release etch removes a substantial portion of the sacrificial layer leaving spacers.

15 . The method according to claim 11 , wherein the polymer layer is a negative photoresist.

16 . The method according to claim 11 , wherein the polymer layer is a positive photoresist.

17 . The method according to claim 11 , further comprising cutting the substrate to form individual MEMS devices without removing the polymer layer.

18 . The method according to claim 17 , wherein the cutting is aligned with the second opening.

19 . A method for manufacturing microelectromechanical systems (MEMS) devices, the method comprising:
forming a MEMS stack over a first main surface of a substrate; thinning the substrate to expose a second main surface; forming a polymer layer over the second main surface; patterning the polymer layer to form a first opening and a second opening, wherein the first opening overlaps with the MEMS stack; filling the second opening with a masking layer; extending the second opening into the substrate such that the first opening abuts the MEMS stack; removing the masking layer after the extending; and performing a release etch to form moveable components of the MEMS devices.

20 . The method according to claim 19 , wherein performing the release etch comprising etching with HF based chemistry.

21 . The method according to claim 19 , wherein the MEMS stack comprises a sacrificial layer disposed between a backplate and a membrane, and wherein the release etch removes all of the sacrificial layer.

22 . The method according to claim 19 , wherein the MEMS stack comprises a sacrificial layer disposed between a backplate and a membrane, and wherein the release etch removes a substantial portion of the sacrificial layer leaving spacers.

Assignees

• Infineon Technologies Ag

Inventors

• Dehe Alfons
• Pindl Stephan
• Knott Bernhard
• Ahrens Carsten

Classifications

• B81C1/00825 Primary

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• H04R19/005

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• B81B2201/0257

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• B81C2201/017

  Methods for controlling internal stress of deposited layers not provided for in B81C2201/0164 - B81C2201/0169 · CPC title

• B81B2201/0264

  Pressure sensors · CPC title