Proof-mass with supporting structure on integrated circuit-MEMS platform and method of fabricating the same

• US 8,094,980 B2
• Filed: 01/04/2010
• Issued: 01/10/2012
• Est. Priority Date: 12/18/2006
• Status: Active Grant

• Current Assignee: Akustica Incorporated
• Original Assignee: Akustica Incorporated
• Inventors: Diamond, Brett M., Zeleznik, Matthew A., Vandemeer, Jan E., Gabriel, Kaigham J.
• Primary Examiner(s): CHAPMAN JR, JOHN E
• Application Number:
  US12/651,551
• Publication Number:
  US 20100147076A1
• Time in Patent Office: 736 Days
• Field of Search: 735/141.8, 735/143.2, 310/309, 359/223.1, 385/18
• US Class Current: 385/18
• CPC Class Codes: B81C 1/00246 Monolithic integration, i.e. micromechanical structure and electronic processing unit are integrated on the same substrate
• CPC Class Codes: B81C 2203/0742 Interleave, i.e. simultaneously forming the micromechanical structure and the CMOS circuit

Abstract

Provided is a micro-electromechanical-system (MEMS) device including a substrate; at least one semiconductor layer provided on the substrate; a circuit region including at least one chip containing drive/sense circuitry, the circuit region provided on the at least one semiconductor layer; a support structure attached to the substrate; at least one elastic device attached to the support structure; a proof-mass suspended by the at least one elastic device and free to move in at least one of the x-, y-, and z-directions; at least one top electrode provided on the at least one elastic device; and at least one bottom electrode located beneath the at least one elastic device such that an initial capacitance is generated between the at least one top and bottom electrodes, wherein the drive/sense circuitry, proof-mass, supporting structure, and the at least one top and bottom electrodes are fabricated on the at least one semiconductor layer.

Claims

1. A micro-electromechanical-system (MEMS) device, comprising:

a substrate;

at least one semiconductor layer provided on the substrate;

a circuit region including at least one chip containing drive/sense circuitry, the circuit region provided on the at least one semiconductor layer;

a support structure attached to the substrate;

at least one elastic device attached to the support structure;

a proof-mass suspended by the at least one elastic device and free to move in all of the x-, y-, and z-directions;

at least one top electrode provided on the at least one elastic device; and

at least one bottom electrode located beneath the at least one elastic device such that an initial capacitance is generated between the at least one top and bottom electrodes;

wherein;

the MEMS device is configured to produce an electrostatic potential between the at least one top electrode and the at least one bottom electrode that applies a force to the suspended proof-mass in at least one of the x-, y-, and z-directions; and

the drive/sense circuitry, proof-mass, support structure, and the at least one top and bottom electrodes are fabricated on the at least one semiconductor layer.

2. The device according to claim 1, wherein the force applied to the proof-mass causes the proof-mass to move in at least one of the x-, y-, and z-directions.

3. The device according to claim 1, wherein the force applied to the proof-mass causes the proof-mass to tilt along at least one of the x-, y-, and z-directions.

4. The device according to claim 1, wherein the drive/sense circuitry generates the electrostatic potential between the at least one top electrode and the at least one bottom electrode.

5. The device according to claim 1, further comprising:

at least one input port in optical communication with the proof-mass; and

at least one output port in optical communication with the proof-mass;

wherein the proof-mass directs light waves from at least one input port to at least one output port.

6. The device according to claim 5, wherein the device is an optical switch.

7. The device according to claim 6, wherein the drive/sense circuitry generates the electrostatic potential between the at least one top and bottom electrodes.

8. The device according to claim 6, wherein the device is one of a plurality employed in an array.

9. The device according to claim 6, wherein the proof-mass forms at least one reflective mirror.

10. The device according to claim 6, wherein the proof-mass forms at least one partially reflective mirror.

11. The device according to claim 6, wherein the proof-mass forms at least one diffraction grating.

12. The device according to claim 6, wherein the proof-mass is transparent to at least one wavelength of light.

13. The device according to claim 6, further comprising at least one optical coating disposed on the proof-mass.

14. The device according to claim 13, wherein the at least one optical coating forms at least one reflective mirror.

15. The device according to claim 13, wherein the at least one optical coating forms at least one partially reflective mirror.

16. The device according to claim 13, wherein the at least one optical coating forms at least one diffraction grating.

17. The device according to claim 13, wherein the at least one optical coating is transparent to at least one wavelength of light.

18. A micro-electromechanical-system (MEMS) device, comprising:

a substrate;

at least one semiconductor layer provided on the substrate;

a circuit region including at least one chip containing drive/sense circuitry, the circuit region provided on the at least one semiconductor layer;

a support structure attached to the substrate;

at least one elastic device attached to the support structure;

a proof-mass suspended by the at least one elastic device and free to move in all of the x-, y-, and z-directions;

at least one conductive layer provided on the at least one elastic device; and

at least one bottom electrode located beneath the at least one elastic device such that an initial capacitance is generated between the at least one top and bottom electrodes;

wherein;

the MEMS device is configured to produce an electrostatic potential between the at least one conductive layer and the at least one bottom electrode that applies a force to the suspended proof-mass in at least one of the x-, y-, and z-directions; and

the drive/sense circuitry, proof-mass, support structure, and the at least one top and bottom electrodes are fabricated on the at least one semiconductor layer.

19. The device according to claim 18, wherein the force applied to the proof-mass causes the proof-mass to move in at least one of the x-, y-, and z-directions.

20. The device according to claim 18, wherein the force applied to the proof-mass causes the proof-mass to tilt along at least one of the x-, y-, and z-directions.

21. The device according to claim 18, wherein the drive/sense circuitry generates the electrostatic potential between the at least one conductive layer and the at least one bottom electrode.