MEMS vibration isolation system and method

• US 8,896,074 B2
• Filed: 01/26/2012
• Issued: 11/25/2014
• Est. Priority Date: 01/26/2012
• Status: Active Grant

• Current Assignee: Charles Stark Draper Laboratory Incorporated
• Original Assignee: Charles Stark Draper Laboratory Incorporated
• Inventors: Bernstein, Jonathan, Weinberg, Marc
• Primary Examiner(s): PERT, EVAN T
• Application Number:
  US13/358,744
• Publication Number:
  US 20130194770A1
• Time in Patent Office: 1,034 Days
• Field of Search: 257/415, 438/50, 438/51
• US Class Current: 257/415
• CPC Class Codes: B81B 7/0016 Protection against shocks or vibrations, e.g. vibration damping

Abstract

A microelectromechanical vibration isolation system includes a microelectromechanical structure having a plurality of fin apertures etched therethrough, and a plurality of fins each disposed within a respective one of the plurality of fin apertures and spaced apart from the microelectromechanical structure so as to define a fluid gap therebetween. The fluid gap is configured to provide squeeze film damping of vibrations imparted upon the microelectromechanical structure in at least two dimensions. The system further includes a frame surrounding the microelectromechanical structure, and a plurality of springs each coupled to the microelectromechanical structure and to the frame. The plurality of springs is configured to support the micromechanical structure in relation to the frame.

Claims

1. A microelectromechanical vibration isolation system, comprising:

a microelectromechanical structure having a plurality of fin apertures etched therethrough;

a plurality of fins each disposed within a respective one of the plurality of fin apertures and spaced apart from the microelectromechanical structure so as to define a fluid gap therebetween, the fluid gap being configured to provide squeeze film damping of vibrations imparted upon the microelectromechanical structure in at least two dimensions;

a frame surrounding the microelectromechanical structure; and

a plurality of springs each coupled to the microelectromechanical structure and to the frame, the plurality of springs being configured to support the micromechanical structure in relation to the frame.

2. The system of claim 1, wherein the fluid gap is a first fluid gap, wherein the system further comprises a substrate mounted adjacent to and spaced apart from the microelectromechanical structure so as to define a second fluid gap between the microelectromechanical structure and the substrate, the second fluid gap being configured to provide additional squeeze film damping of the vibrations in at least one dimension.

3. The system of claim 2, wherein each of the plurality of fins is coupled to the substrate and extends outwardly therefrom.

4. The system of claim 2, wherein the microelectromechanical structure includes at least one damping region opposing at least a portion of the second fluid gap, the at least one damping region being free of fin apertures.

5. The system of claim 2, wherein a thickness of the substrate is in a range of approximately 50 to 1000 microns.

6. The system of claim 1, wherein each of the plurality of fins is coupled to the frame and extends outwardly therefrom toward the micromechanical structure.

7. The system of claim 6, further comprising an enclosure surrounding the micromechanical structure, wherein the fluid gap is a first fluid gap, wherein the micromechanical structure includes at least one damping region spaced apart from at least a portion of the enclosure so as to define a second fluid gap therebetween, wherein the second fluid gap is configured to provide additional squeeze film damping of the vibrations, and wherein the at least one damping region is free of fin apertures.

8. The system of claim 1, further comprising a plurality of electrical contacts disposed upon the microelectromechanical structure.

9. The system of claim 8, wherein each of the plurality of springs is coupled to a respective one of the plurality of electrical contacts.

10. The system of claim 8, wherein the plurality of electrical contacts includes at least one bump bond pad.

11. The system of claim 8, wherein the plurality of electrical contacts is a first plurality of electrical contacts, and wherein the system further comprises a second plurality of electrical contacts disposed upon the frame, each of the second plurality of electrical contacts being electrically coupled to a respective one of the first plurality of electrical contacts.

12. The system of claim 8, wherein the microelectromechanical structure is configured to support an instrument module thereupon, and wherein the plurality of electrical contacts is configured to be electrically coupled to the instrument module.

13. The system of claim 1, wherein the fluid gap contains a gas.

14. The system of claim 13, wherein the gas includes nitrogen.

15. The system of claim 1, wherein the fluid gap contains at least one of an oil and a grease.

16. The system of claim 1, wherein the fluid gap is between approximately 2 and 250 microns wide.

17. The system of claim 1, wherein the system is configured to occupy a volume of approximately 10 cubic millimeters or less.

18. The system of claim 1, wherein at least one of the plurality of fins is concentric with another of the plurality of fins.

19. The system of claim 1, wherein the plurality of springs includes at least one folded spring.

20. The system of claim 1, wherein the plurality of springs is configured to provide damping of at least some of the vibrations.

21. A microelectromechanical vibration isolation system, comprising:

a microelectromechanical structure having a plurality of recesses etched therein;

a frame surrounding the microelectromechanical structure;

means for coupling the microelectromechanical structure to the frame such that the micromechanical structure is supported in relation to the frame; and

means for damping vibrations imparted upon the microelectromechanical structure including a plurality of damping structures each disposed within a respective one of the plurality of recesses.

22. The system of claim 21, wherein the plurality of damping structures is oriented substantially perpendicular to a plane of the microelectromechanical structure.

23. The system of claim 21, wherein the plurality of damping structures is oriented substantially parallel to a plane of the microelectromechanical structure.

24. The system of claim 21, wherein the plurality of damping structures includes at least one squeeze film damper.

25. The system of claim 24, wherein the at least one squeeze film damper includes a gas.

26. The system of claim 21, wherein the plurality of damping structures includes at least one spring coupled to the microelectromechanical structure and to the frame.