Micro-electro-mechanical system (MEMS) device

Patent metadata

Field	Value
Publication number	US-9702889-B2
Application number	US-201514742393-A
Country	US
Kind code	B2
Filing date	Jun 17, 2015
Priority date	Jun 17, 2015
Publication date	Jul 11, 2017
Grant date	Jul 11, 2017

Abstract

The present invention discloses a MEMS device. The MEMS device includes a substrate, a proof mass, a frame spring and an anchor. The proof mass is connected to the substrate through the frame spring and the anchor. The proof mass includes a proof mass body, a proof mass frame surrounding the proof mass body, a linking element connecting the proof mass body to the proof mass frame, and a stopper between the proof mass body and the proof mass frame in a displacement direction to limit the displacement of the proof mass body. The stopper is connected to the proof mass frame as a part of the proof mass and contributes to the mass quantity of the proof mass.

First claim

What is claimed is:

1. A Micro-Electron-Mechanical System (MEMS) device, comprising:
a substrate;
a proof mass suspended above the substrate and is movable relatively to the substrate, wherein the proof mass includes:
at least one proof mass body;
a proof mass frame surrounding the proof mass body;
at least one linking element connecting the proof mass body to the proof mass frame, the linking element providing a spring function so that the proof mass body is movable relatively to the proof mass frame in a displacement direction; and
at least one stopper between the proof mass body and the proof mass frame in the displacement direction to limit the displacement of the proof mass body, wherein the stopper is connected to the proof mass frame or the proof mass body as a part of the proof mass and contributes to the mass quantity of the proof mass;

at least one frame spring connected to the proof mass frame; and
at least one anchor connecting one or more of the at least one frame spring to the substrate,
wherein the stopper includes a first part extending in the displacement direction and a second part extending in a direction perpendicular to the displacement direction, the stopper being connected to the proof mass frame or the proof mass body by the first part, the second part being longer than the first part, and the second part having one end connected to the first part and another end open.

2. The MEMS device of claim 1 , wherein the stopper is wholly made of a resilient material, or a part of the stopper which is connected to the proof mass frame or the proof mass body is made of a resilient material.

3. The MEMS device of claim 1 , wherein the stopper as a whole, or a part of the stopper which is connected to the proof mass frame or the proof mass body, provides an impact buffering function by a shape of the stopper or a shape of the part of the stopper.

4. The MEMS device of claim 1 , wherein the anchor is located outside the proof mass frame.

5. The MEMS device of claim 1 , wherein the anchor is located inside the proof mass frame.

6. The MEMS device of claim 1 , wherein the anchor is located below the proof mass body.

7. The MEMS device of claim 1 , further comprising a buffer spring between the stopper and the proof mass frame in the displacement direction.

8. The MEMS device of claim 1 , further comprising a buffer spring between the stopper and the proof mass body in the displacement direction.

9. The MEMS device of claim 1 , further comprising a first buffer spring between the stopper and the proof mass frame in the displacement direction, and a second buffer spring between the stopper and the proof mass body in the displacement direction.

10. The MEMS device of claim 1 , wherein the MEMS device comprises at least two proof mass bodies, and the MEMS device further comprises at least another stopper between the two proof mass bodies in the displacement direction.

11. The MEMS device of claim 1 , wherein the stopper is connected to a side of the proof mass frame or a side of the proof mass body which is not parallel to the displacement direction.

12. The MEMS device of claim 1 , wherein at least one of the linking elements includes a first part connected to the proof mass frame and a plurality of second parts connected to the proof mass body.

13. The MEMS device of claim 12 , wherein at least one of the second parts provides a spring function, and the first part is relatively more rigid than this second part.

14. The MEMS device of claim 12 , wherein at least one of the second parts extends between the stopper and the proof mass frame.

15. The MEMS device of claim 1 , wherein the proof mass body has an internal space, and the stopper is connected to the proof mass frame and extends in the internal space.

16. A Micro-Electron-Mechanical System (MEMS) device, comprising:
a substrate;
a proof mass suspended above the substrate and is movable relatively to the substrate, wherein the proof mass includes:
at least two proof mass bodies;
a proof mass frame surrounding the proof mass bodies;
at least two linking elements connecting the proof mass bodies to the proof mass frame, respectively, the linking elements providing a spring function so that the proof mass bodies are movable relatively to the proof mass frame in a displacement direction; and
at least one stopper between the proof mass bodies in the displacement direction to limit the displacements of the proof mass bodies, wherein the stopper is connected to the proof mass frame as a part of the proof mass and contributes to the mass quantity of the proof mass;

at least one frame spring connected to the proof mass frame; and
at least one anchor connecting one or more of the at least one frame spring to the substrate.

Assignees

• Lin Shih-Chieh
• Lo Chiung-Cheng
• Richtek Technology Corp

Inventors

• Lin Shih-Chieh
• Lo Chiung-Cheng

Classifications

• G01P15/18

  in two or more dimensions · CPC title

• G01P2015/0814

  for translational movement of the mass, e.g. shuttle type · CPC title

• G01P2015/0822

  for defining out-of-plane movement of the mass · CPC title

• G01P2015/0871

  using stopper structures for limiting the travel of the seismic mass · CPC title

• G01P1/003 Primary

  used for damping · CPC title