Micromachined artificial haircell

• US 20080072683A1
• Filed: 06/01/2007
• Published: 03/27/2008
• Est. Priority Date: 06/02/2006
• Status: Active Grant

• Current Assignee: University of Illinois
• Original Assignee: Board of Trustees of The University of Illinois
• Inventors: Liu, Chang, Chen, Nannan, Chen, Jack, Engel, Jonathan
• Granted Patent: US 7,661,319 B2
• Time in Patent Office: Days
• US Class Current: 73/774
• CPC Class Codes: B81B 2201/0292 Sensors not provided for in B81B2201/0207 - B81B2201/0285
• CPC Class Codes: B81B 2203/0118 Cantilevers
• CPC Class Codes: B81B 3/0021 Transducers for transforming electrical into mechanical energy or vice versa dynamo-electric machines H02K99/00; electrostatic machines H02N1/00; piezoelectric devices H10N30/00
• CPC Class Codes: G01P 15/0802 Details
• CPC Class Codes: G01P 15/123 by piezo-resistive elements, e.g. semiconductor strain gauges
• CPC Class Codes: G01P 5/04 using deflection of baffle-plates

Abstract

A micromachined artificial sensor comprises a support coupled to and movable with respect to a substrate. A polymer, high-aspect ratio cilia-like structure is disposed on and extends out-of-plane from the support. A strain detector is disposed with respect to the support to detect movement of the support.

Claims

1. A micromachined artificial sensor comprising:

a support coupled to and movable with respect to a substrate;

a polymer, high-aspect ratio cilia-like structure disposed on and extending out-of-plane from said support;

a strain detector disposed with respect to said support to detect movement of said support.

2. The artificial sensor of claim 1, wherein said support comprises silicon.

3. The artificial sensor of claim 2, wherein said support is formed by micromachining the substrate to provide a cavity disposed under said support.

4. The artificial sensor of claim 1, wherein said support comprises at least one cantilevered beam.

5. The artificial sensor of claim 1, wherein said support comprises a paddle supported by at least two cantilevered beams, and wherein said cilia-like structure is disposed on said paddle.

6. The artificial sensor of claim 1, wherein said support comprises silicon, and wherein said strain detector comprises a piezoresistive strain gauge formed by doping a portion of said support.

7. The artificial sensor of claim 6, wherein the strain gauge is disposed at or near a connection between said support and the substrate.

8. The artificial sensor of claim 1, wherein said cilia-like structure comprises a generally cylindrical structure having an aspect ratio of greater than 1:

1 height;

diameter.

9. The artificial sensor of claim 1, wherein said cilia-like structure comprises an epoxy.

10. The artificial sensor of claim 1, wherein said cilia-like structure comprises SU-8 epoxy spun onto said support.

11. The artificial sensor of claim 1, further comprising:

a transducer disposed on said cilia-like structure that deforms or moves in response to a stimulus to move said cilia-like structure.

12. The artificial sensor of claim 11, wherein said transducer comprises at least one of a magnetic transducer, a vibration transducer, an acoustic transducer, a chemical transducer, a biological transducer, and a biochemical transducer.

13. A micromachined sensing apparatus comprising:

a silicon substrate;

a silicon support coupled to and movable with respect to said substrate, wherein a cavity is defined beneath said support;

a polymer, high-aspect ratio cilia-like structure disposed on and extending out-of-plane from said support;

a strain detector disposed with respect to said support to detect movement of said support.

14. The sensing apparatus of claim 13, wherein said support is formed by micromachining said silicon substrate, and wherein said strain detector is formed by doping a portion of said silicon support to provide a piezoresistive strain gauge.

15. The sensing apparatus of claim 13, wherein said cilia-like structure comprises a generally cylindrical structure having an aspect ratio of greater than 1:

1 height;

diameter.

16. The sensing apparatus of claim 13, further comprising:

a transducer disposed on said cilia-like structure that deforms or moves in response to a stimulus to move said cilia-like structure.

17. The sensing apparatus of claim 13, further comprising:

an additional silicon support coupled to and movable with respect to said substrate, wherein a cavity is defined beneath said additional support;

an additional polymer, high-aspect ratio cilia-like structure disposed on and extending out-of-plane from said additional support;

an additional strain detector disposed with respect to said additional support to detect movement of said additional support;

wherein said additional silicon support is disposed on said substrate at an angle with respect to said silicon support.

18. The sensing apparatus of claim 17, wherein said additional silicon support, said additional cilia-like structure, and said additional strain detector are disposed to have an optimal flow sensitivity at a different angle than an optimal flow sensitivity of said silicon support, said cilia-like structure, and said strain detector.

19. The sensing apparatus of claim 17, wherein said additional silicon support has a longitudinal axis that is generally orthogonal to a longitudinal axis of said silicon support.

20. A micromachined artificial sensor comprising:

silicon-based movable means for support;

polymer high-aspect ratio means for receiving a force and coupling the force to said movable means, said high-aspect ratio means being mounted to and extending generally out of plane of said movable means; and

means for detecting strain based on displacement of said high-aspect ratio means.