Micro-electromechanical system device and method of forming the same

Patent metadata

Field	Value
Publication number	US-2022024753-A1
Application number	US-202016937552-A
Country	US
Kind code	A1
Filing date	Jul 23, 2020
Priority date	Jul 23, 2020
Publication date	Jan 27, 2022
Grant date	—

Abstract

The present disclosure related to a micro-electromechanical system (MEMS) device and a method of forming the same. The MEMS device includes a substrate, a cavity, an interconnection structure and a proof mass. The substrate includes a first surface and a second surface opposite to the first surface. The cavity is disposed in the substrate to extend between the first surface and the second surface. The interconnection structure is disposed on the first surface of the substrate, over the cavity. The proof mass is disposed on the interconnection structure, wherein the proof mass is partially suspended over the interconnection structure.

First claim

What is claimed is:

1 . A micro-electromechanical system device comprising:
a substrate, comprising a first surface and a second surface opposite to the first surface; a cavity disposed in the substrate, extending between the first surface and the second surface; an interconnection structure disposed on the first surface of the substrate, over the cavity; and a proof mass disposed on the interconnection structure, wherein the proof mass is partially suspended over the interconnection structure.

2 . The micro-electromechanical system device accordingly to claim 1 , wherein the proof mass further comprises a base layer and a mass layer, the base layer is directly disposed on the interconnection structure, and the mass layer is disposed on the base layer.

3 . The micro-electromechanical system device accordingly to claim 2 , wherein one end of the mass layer is disposed on the base layer, and another end of the mass layer is suspended over the interconnection structure.

4 . The micro-electromechanical system device accordingly to claim 2 , wherein the mass layer further comprises a protrusion surrounding a sidewall of the base layer.

5 . The micro-electromechanical system device accordingly to claim 4 , wherein the protrusion directly contacts the interconnection structure.

6 . The micro-electromechanical system device accordingly to claim 2 , wherein the interconnection structure further comprises a suspended region corresponding to the cavity, and a first end of the suspended region directly connect to the substrate and a second end of the suspended region not directly connect to the substrate.

7 . The micro-electromechanical system device accordingly to claim 6 , wherein the base layer is disposed adjacent to the second end of the suspended region.

8 . The micro-electromechanical system device accordingly to claim 6 , wherein the mass layer is extended from the first end of the suspended region to the second end of the suspended region.

9 . The micro-electromechanical system device accordingly to claim 1 , further comprising an oxide layer disposed between the interconnection structure and the substrate.

10 . The micro-electromechanical system device accordingly to claim 1 , wherein the cavity has a thickness the same as a thickness of the substrate.

11 . The micro-electromechanical system device accordingly to claim 1 , wherein at least one end of the proof mass is suspended over the interconnection structure.

12 . A method of fabricating micro-electromechanical system device comprising:
providing a substrate, the substrate comprising a first surface and a second surface opposite to the first surface; forming a cavity in the substrate, the cavity extending between the first surface and the second surface; forming an interconnection structure on the first surface of the substrate, over the cavity; and forming a proof mass on the interconnection structure, wherein the proof mass is partially suspended over the interconnection structure.

13 . The method of fabricating micro-electromechanical system device accordingly to claim 12 , wherein the proof mass is formed after forming the cavity.

14 . The method of fabricating micro-electromechanical system device accordingly to claim 12 , wherein the forming of the proof mass further comprises:
forming a base layer on the interconnection structure; and forming a mass layer.

15 . The method of fabricating micro-electromechanical system device accordingly to claim 14 , further comprising:
forming a base material layer on the interconnection structure; before forming the cavity, forming the mass layer on the base material layer; and after forming the cavity, partially removing the base material layer to form the base layer.

16 . The method of fabricating micro-electromechanical system device accordingly to claim 15 , further comprising:
before forming the cavity, forming a hole in the base material layer; and forming the mass layer, wherein the mass layer comprises a protrusion filled in the hole.

17 . The method of fabricating micro-electromechanical system device accordingly to claim 16 , wherein the protrusion surrounds a sidewall of the base layer and directly contacts the interconnection structure.

18 . The method of fabricating micro-electromechanical system device accordingly to claim 12 , further comprising:
forming an oxide layer between the interconnection structure and the substrate; and after forming the cavity, partially removing the oxide layer to connect the cavity with the interconnection structure.

19 . The method of fabricating micro-electromechanical system device accordingly to claim 12 , wherein the forming of the cavity comprises:
partially removing the substrate from the second surface.

20 . The method of fabricating micro-electromechanical system device accordingly to claim 12 , wherein at least one end of the proof mass is suspended over the interconnection structure.

Assignees

• Vanguard Int Semiconduct Corp

Inventors

• Xia jia jie

Classifications

• H04R2201/107

  Monophonic and stereophonic headphones with microphone for two-way hands free communication · CPC title

• H04R31/00

  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)} · CPC title

• H04R17/02

  Microphones · CPC title

• B81C1/00182

  Arrangements of deformable or non-deformable structures, e.g. membrane and cavity for use in a transducer · CPC title

• B81B2201/0235

  Accelerometers · CPC title