MEMS device and method of manufacturing a MEMS device

• US 9,938,140 B2
• Filed: 07/11/2016
• Issued: 04/10/2018
• Est. Priority Date: 10/12/2012
• Status: Active Grant

• Current Assignee: Infineon Technologies AG
• Original Assignee: Infineon Technologies AG
• Inventors: Dehe, Alfons, Pindl, Stephan, Knott, Bernhard, Ahrens, Carsten
• Primary Examiner(s): INOUSSA, MOULOUCOULAY
• Application Number:
  US15/206,836
• Publication Number:
  US 20160318759A1
• Time in Patent Office: 638 Days
• Field of Search: 257415, 257E29324, 257E2104, 257416, 257E29, 257E21, 438694, 438 52, 438 14, 438 53, 438 51
• CPC Class Codes: B81B 2201/0235 Accelerometers
• CPC Class Codes: B81B 2201/0257 Microphones or microspeakers
• CPC Class Codes: B81B 2201/0264 Pressure sensors
• CPC Class Codes: B81C 1/00825 Protect against mechanical threats, e.g. against shocks, or residues B81C1/00261 take precedence
• CPC Class Codes: B81C 1/00873 characterised by special arrangements of the devices, allowing an easier separation
• CPC Class Codes: B81C 2201/017 Methods for controlling internal stress of deposited layers not provided for in B81C2201/0164 - B81C2201/0169
• CPC Class Codes: B81C 2201/053 Depositing a protective layers
• 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 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 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 on a first main surface of a substrate, forming a polymer layer on 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.

Claims

1. A method for manufacturing microelectromechanical systems (MEMS) devices, the method comprising:

forming a MEMS stack on a first main surface of a substrate;

mounting the MEMS stack on a carrier, the first main surface facing the carrier;

thinning the substrate from an opposite main surface to expose a second main surface;

depositing a polymer layer on the second main surface of the substrate;

forming a first opening in the polymer layer and the substrate, wherein the first opening is formed directly below the MEMS stack;

removing the carrier;

performing a release etch to form moveable components of the MEMS devices after forming the first opening; and

without removing the polymer layer, cutting the substrate to form individual MEMS devices so that each of the individual MEMS devices after the cutting includes a portion of the polymer layer.

2. The method according to claim 1, wherein the MEMS stack comprises a sacrificial layer, and wherein the sacrificial layer is disposed over the entire first main surface of the substrate.

3. The method according to claim 1, further comprising:

forming a second opening in the polymer layer while forming the first opening in the polymer layer; and

forming a third opening in the polymer layer between the second opening and the first opening, the third opening being formed around the first opening.

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

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

6. The method according to claim 1, wherein the MEMS stack comprises a backplate and a membrane.

7. A method for manufacturing microelectromechanical systems (MEMS) devices, the method comprising:

forming a MEMS stack on a first main surface of a substrate;

mounting the MEMS stack on a carrier, the first main surface facing the carrier;

thinning the substrate from an opposite main surface to expose a second main surface;

depositing a polymer layer on the second main surface of the substrate;

forming a first opening in the polymer layer and the substrate, wherein the first opening is formed directly below the MEMS stack;

forming a second opening in the polymer layer and the substrate during the forming of the first opening in the polymer layer;

removing the carrier;

performing a release etch to form moveable components of the MEMS devices after forming the first opening; and

without removing the polymer layer, cutting the substrate to form individual MEMS devices.

8. The method according to claim 7, further comprising:

forming an etch stop layer on the second main surface of the substrate, the etch stop layer not covering portions of the substrate opposite the MEMS stack.

9. The method according to claim 8, wherein the etch stop layer is an etch stop during the forming of the first opening and the second opening.

10. The method according to claim 7, wherein the MEMS stack comprises a sacrificial layer, and wherein the sacrificial layer is disposed over the entire first main surface of the substrate.

11. The method according to claim 7, further comprising:

forming a second opening in the polymer layer while forming the first opening in the polymer layer; and

forming a third opening in the polymer layer between the second opening and the first opening, the third opening being formed around the first opening.

12. The method according to claim 7, wherein the polymer layer is a negative photoresist.

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

14. The method according to claim 7, wherein the MEMS stack comprises a backplate and a membrane.

15. A method for manufacturing microelectromechanical systems (MEMS) devices, the method comprising:

forming a MEMS stack on a first main surface of a substrate;

mounting the MEMS stack on a carrier, the first main surface facing the carrier;

thinning the substrate from an opposite main surface to expose a second main surface;

forming an etch stop layer on the second main surface of the substrate, the etch stop layer not covering portions of the substrate opposite the MEMS stack;

depositing a polymer layer on the second main surface of the substrate and on the etch stop layer;

forming a first opening in the polymer layer and the substrate, wherein the first opening is formed directly below the MEMS stack;

removing the carrier;

performing a release etch to form moveable components of the MEMS devices after forming the first opening; and

without removing the polymer layer, cutting the substrate to form individual MEMS devices.

16. The method according to claim 15, wherein the MEMS stack comprises a sacrificial layer, and wherein the sacrificial layer is disposed over the entire first main surface of the substrate.

17. The method according to claim 15, further comprising forming a second opening in the polymer layer and the substrate during the forming of the first opening in the polymer layer.

18. The method according to claim 17, wherein the etch stop layer is an etch stop during the forming of the first opening and the second opening.

19. The method according to claim 15, further comprising:

forming a second opening in the polymer layer while forming the first opening in the polymer layer; and

forming a third opening in the polymer layer between the second opening and the first opening, the third opening being formed around the first opening.

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

21. The method according to claim 15, wherein the polymer layer is a positive photoresist.

22. The method according to claim 15, wherein the MEMS stack comprises a backplate and a membrane.