Fiber based MEMS

• US 20060007514A1
• Filed: 06/24/2005
• Published: 01/12/2006
• Est. Priority Date: 06/24/2004
• Status: Active Grant

• Current Assignee: Cornell Research Foundation Incorporated (Cornell University)
• Original Assignee: Cornell Research Foundation Incorporated (Cornell University)
• Inventors: Desai, Shahyaan
• Granted Patent: US 7,457,021 B2
• Time in Patent Office: Days
• US Class Current: 359/223.100
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: G02B 26/0833 the reflecting element being a micromechanical device, e.g. a MEMS mirror, DMD G02B26/0825 takes precedence; micromechanical devices in general B81B
• CPC Class Codes: G02B 6/3512 the optical element being reflective, e.g. mirror
• CPC Class Codes: G02B 6/3566 involving bending a beam, e.g. with cantilever
• CPC Class Codes: G02B 6/357 Electrostatic force electrostatic forces controlling reflecting elements in general G02B26/0841
• CPC Class Codes: G02B 6/3572 Magnetic force magnetic forces controlling reflecting elements in general G02B26/085; magneto-optic devices G02F1/09
• CPC Class Codes: G02B 6/3578 Piezoelectric force piezoelectric forces controlling reflecting elements in general G02B26/0858; piezo-optic devices G02F1/0131
• CPC Class Codes: G02B 6/3584 constructional details of an associated actuator having a MEMS construction, i.e. constructed using semiconductor technology such as etching MEMS per se B81B, B81C
• CPC Class Codes: Y10T 29/49826 Assembling or joining

Abstract

MEMS can be fabricated from fibers without the use of a matrix material. Devices can be built where fibers are attached only at a substrate edge (e.g. cantilevers, bridges). Motions can be controlled by adjusting the linkage between multiple fibers with weak coupling (e.g. base, tip, in-between). Driving mechanisms include base-forcing (magnetics, piezo, electrostatics) or tip forcing (magnetics). Mirrors may be formed on free ends of cantilevers to form optical scanners.

Claims

1. A micro-electro-mechanical device scanner comprising:

a substrate;

an array of fibers supported by the substrate at a clamped end of the array of fibers; and

a mirror coupled to a second, free end of the array of fibers.

2. The micro-electro-mechanical device scanner of claim 1 wherein the array of fibers comprises multiple fibers arranged adjacent to and approximately parallel to each other.

3. The micro-electro-mechanical device scanner of claim 1 wherein the array of fibers is supported a top side of the substrate, and wherein the mirror has a reflective surface facing a bottom side of the substrate.

4. The micro-electro-mechanical device scanner of claim 3 wherein the mirror is formed of a reflective film. (aluminum, titanium, gold, ceramic films such as dichroics)

5. The micro-electro-mechanical device scanner of claim 4 wherein the mirror comprises a backing for support.

6. The micro-electro-mechanical device scanner of claim 5 wherein the backing comprises Si₃N₄.

7. The micro-electro-mechanical device scanner of claim 1 wherein a portion of the array of fibers between the clamped and the free ends is exposed.

8. The micro-electro-mechanical device scanner of claim 1 wherein the substrate is coupled to a free end of a cantilever.

9. The micro-electro-mechanical device scanner of claim 1 wherein the array of fibers forms a first cantilever which is supported by the substrate through a second cantilever.

10. The micro-electro-mechanical device scanner of claim 1 wherein the second cantilever is formed of ferromagnetic material.

11. The micro-electro-mechanical device scanner of claim 10 and further comprising means for oscillating the free end of the array of fibers.

12. The micro-electro-mechanical device scanner of claim 10 wherein the means for oscillating the free end of the array of fibers comprises selected fibers in the array that are responsive to selected stimulus.

13. The micro-electro-mechanical device scanner of claim 12 wherein the selected fibers are selected from the group consisting of magnetic, piezoelectric, electrostatic, electrothermal, and electrostrictive responsive fibers.

14. A scanner comprising:

a substrate;

an array of carbon fibers supported by the substrate at a clamped end of the array of fibers; and

a mirror coupled to a second, free end of the array of carbon fibers, wherein at least a portion of the array of carbon fibers is exposed.

15. The scanner of claim 14 wherein the mirror a substantially flat unpolished reflective surface.

16. The scanner of claim 14 wherein the carbon fibers have diameters ranging between approximately 10 nm to 10 um.

17. The scanner of claim 14 wherein the mirror may be moved through angles of greater than plus or minus approximately 80°

at frequencies exceeding 30 kHz by the array of carbon fibers.

18. The scanner of claim 14 wherein the array of carbon fibers is supported a top side of the substrate, and wherein the mirror has a reflective surface facing a bottom side of the substrate.

19. The scanner of claim 18 wherein the reflective surface of the mirror was formed from aluminum deposited on a selectively etchable deposited material having a substantially flat surface.

20. The scanner of claim 19 wherein the selectively etchable deposited material is Si₃N₄.

21. The scanner of claim 14 wherein the fibers are supported by the substrate in grooves.

22. A scanner comprising:

a substrate;

a cantilever formed of one or more fibers supported by the substrate at a clamped end of the cantilever on a top side of the substrate; and

a mirror coupled to a second, free end of the cantilever, wherein the mirror has a reflective surface on one side of the substrate, wherein the mirror is accessible by light from such one side of the substrate.

23. The micro-electro-mechanical device scanner of claim 22 wherein the mirror is formed of aluminum.

24. The micro-electro-mechanical device scanner of claim 23 wherein the mirror comprises a backing for support.

25. The scanner of claim 24 wherein the backing comprises Si₃N₄.

26. The optical scanner of claim 22 wherein the fibers provide for movement about two separate axis.