Stressed decoupled micro-electro-mechanical system sensor

Patent metadata

Field	Value
Publication number	US-10870575-B2
Application number	US-201816024339-A
Country	US
Kind code	B2
Filing date	Jun 29, 2018
Priority date	Jun 29, 2018
Publication date	Dec 22, 2020
Grant date	Dec 22, 2020

Abstract

A semiconductor device may include a stress decoupling structure to at least partially decouple a first region of the semiconductor device and a second region of the semiconductor device. The stress decoupling structure may include a set of trenches that are substantially perpendicular to a main surface of the semiconductor device. The first region may include a micro-electro-mechanical (MEMS) structure. The semiconductor device may include a sealing element to at least partially seal openings of the stress decoupling structure.

First claim

What is claimed is:

1. A semiconductor device, comprising:
a stress decoupling structure to at least partially decouple a first region of the semiconductor device and a second region of the semiconductor device,
wherein the stress decoupling structure includes a set of trenches that are substantially perpendicular to a main surface of the semiconductor device, and
wherein the first region includes a micro-electro-mechanical (MEMS) structure; and

a sealing element to at least partially seal openings of the set of trenches of the stress decoupling structure,
wherein the sealing element includes a cap that includes another stress decoupling structure to decouple the first region and the second region.

2. The semiconductor device of claim 1 , wherein the stress decoupling structure further includes a cavity that at least partially separates the first region from the second region.

3. The semiconductor device of claim 1 , wherein the cap is formed from silicon or glass.

4. The semiconductor device of claim 1 , wherein the cap is affixed to the first region and the second region using a wafer bonding process.

5. The semiconductor device of claim 1 , wherein the cap is formed from an elastic material.

6. The semiconductor device of claim 5 , wherein the elastic material at least partially fills the set of trenches of the stress decoupling structure.

7. The semiconductor device of claim 1 , further comprising a molded package including an opening over the MEMS structure.

8. The semiconductor device of claim 1 , further comprising a gel that covers the MEMS structure.

9. A micro-electro-mechanical system (MEMS) sensor, comprising:
a first region comprising a MEMS structure;
a second region;
a stress decoupling structure that at least partially decouples the first region and the second region,
wherein the stress decoupling structure includes a set of trenches; and

a sealing element to at least partially seal openings of the set of trenches to prevent penetration of the set of trenches,
wherein the sealing element includes a gel.

10. The MEMS sensor of claim 9 , wherein the stress decoupling structure further includes a cavity that at least partially separates the first region from the second region.

11. The MEMS sensor of claim 9 , wherein the sealing element further includes a gel protection cap.

12. The MEMS sensor of claim 11 , wherein the gel protection cap has an open sidewall.

13. The MEMS sensor of claim 11 , wherein the gel protection cap comprises a same material as the MEMS structure.

14. The MEMS sensor of claim 9 , wherein the gel covers the MEMS structure.

15. The MEMS sensor of claim 9 , wherein a portion of the second region overhangs the set of trenches such that the gel is prevented from entering the set of trenches by the portion of the second region, and
wherein the portion of the second region is a portion of a back-end of line (BEOL) stack of the MEMS sensor.

16. A method, comprising:
forming a stress decoupling structure that at least partially decouples a first region of a semiconductor device and a second region of the semiconductor device,
wherein the stress decoupling structure includes a set of trenches that are substantially perpendicular to a main surface of the semiconductor device; and

applying a sealing element that at least partially seals openings of the set of trenches,
wherein the sealing element includes a die attach material.

17. The method of claim 16 , wherein forming the stress decoupling structure comprises:
forming the stress decoupling structure on a surface of the semiconductor device that is opposite to the main surface of the semiconductor device.

18. The method of claim 17 , wherein the first region comprises a micro-electro-mechanical system (MEMS) structure on the main surface of the semiconductor device.

19. The method of claim 16 , wherein the first region comprises a micro-electro-mechanical system (MEMS) structure, and
wherein the method further comprises:
covering the MEMS structure using a gel.

20. The method of claim 16 , wherein forming the stress decoupling structure that at least partially decouples the first region of the semiconductor device and the second region of the semiconductor device comprises:
forming a cavity that at least partially separates the first region from the second region.

Assignees

• Infineon Tech Dresden Gmbh & Co Kg

Inventors

• Theuss Horst
• Knott Bernhard
• Kautzsch Thoralf
• Vogt Mirko
• Stegemann Maik
• Roeth Andre
• Haubold Marco
• Froehlich Heiko
• Langheinrich Wolfram
• Bieselt Steffen

Classifications

• H10W74/01

  Manufacture or treatment · CPC title

• H10W42/121

  protecting against mechanical damage (H10W76/00, H10W74/00 take precedence) · CPC title

• H10W20/43

  Layouts of interconnections · CPC title

• H10W74/10

  characterised by their shape or disposition · CPC title

• H10W72/884

  Die-attach connectors and bond wires · CPC title