Microelectro-mechanical system actuator device and reconfigurable circuits utilizing same

• US 6,127,908 A
• Filed: 11/17/1997
• Issued: 10/03/2000
• Est. Priority Date: 11/17/1997
• Status: Expired due to Fees

• Current Assignee: Massachusetts Institute of Technology
• Original Assignee: Massachusetts Institute of Technology
• Inventors: Kushner, Lawrence J., Bozler, Carl O., Parr, Robert J., Drangmeister, Richard G.
• Primary Examiner(s): Pascal, Robert
• Assistant Examiner(s): Summons, Barbara
• Application Number:
  US08/972,224
• Time in Patent Office: 1,051 Days
• Field of Search: 333/101, 333/33, 333/105, 333/202, 333/262, 333/263, 333/246, 336/10, 338/92, 338/96, 338/97, 338/200-202, 330/66, 361/277, 361/278, 361/281, 361/287, 361/292
• US Class Current: 333/246
• CPC Class Codes: B81B 2201/014 having a cantilever fixed on one side connected to one or more dimples
• 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: B81C 1/00214 Processes for the simultaneaous manufacturing of a network or an array of similar microstructural devices
• CPC Class Codes: H01G 5/18 due to change in inclination, e.g. by flexing, by spiral wrapping
• CPC Class Codes: H01G 5/40 Structural combinations of variable capacitors with other electric elements not covered by this subclass, the structure mainly consisting of a capacitor, e.g. RC combinations
• CPC Class Codes: H01H 2059/0081 with a tapered air-gap between fixed and movable electrodes
• CPC Class Codes: H01H 59/0009 making use of micromechanics
• CPC Class Codes: H01P 1/12 by mechanical chopper
• CPC Class Codes: H01P 1/20327 Electromagnetic interstage coupling
• CPC Class Codes: H01P 1/20363 Linear resonators
• CPC Class Codes: H01P 1/20381 Special shape resonators
• CPC Class Codes: H01P 1/2039 Galvanic coupling between Input/Output
• CPC Class Codes: H01P 5/04 with variable factor of coupling

Abstract

A microelectro-mechanical device which includes a fixed electrode formed on a substrate, the fixed electrode including a transparent, high resistance layer, and a moveable electrode formed with an anisotropic stress in a predetermined direction and disposed adjacent the fixed electrode. The device includes first and second electrically conductive regions which are isolated from one another by the fixed electrode. The moveable electrode moves to cover the fixed electrode and to electrically couple to the second conductive region, thus electrically coupling the first and second conductive regions, in response to a potential being applied across the fixed and moveable electrodes. The fixed electrode is transparent to electromagnetic signals or waves and the moveable electrode impedes or allows transmission of electromagnetic signals or waves. In one embodiment of the invention, the fixed and moveable electrodes are configured within an array of similar devices, and each device or groups of devices in the array are individually addressable to actuate the moveable electrodes. In another embodiment of the invention, there is provided a reconfigurable circuit including an array of actuatable devices which are addressed individually or in selected groups, each of the actuatable devices having a fixed electrode formed on a substrate, the fixed electrode including a transparent, high resistance layer, and a moveable electrode formed with an anisotropic stress in a predetermined direction and disposed adjacent the fixed electrode.

Claims

1. A microelectro-mechanical device comprising:

a fixed electrode formed on a substrate, said fixed electrode including an electrically conducting transparent, high resistance layer;

a moveable electrode disposed adjacent said fixed electrode;

first and second electrically conductive regions which are isolated from one another by said fixed electrode, said moveable electrode being electrically coupled to said first conductive region.

2. The device of claim 1, wherein said fixed and moveable electrodes are configured within an array of similar devices.

3. The device of claim 2, wherein each device or groups of devices in said array are individually addressable to actuate said moveable electrodes.

4. The device of claim 1, wherein said moveable electrode moves to cover said fixed electrode and to electrically couple to said second conductive region, thus electrically coupling said first and second conductive regions, in response to a potential being applied across said fixed and moveable electrodes.

5. The device of claim 4, wherein said potential is applied directly to said fixed electrode and capacitively to said moveable electrode via a second fixed electrode.

6. The device of claim 5, wherein said second fixed electrode comprises a transparent, high resistance layer.

7. The device of claim 4, wherein the electrical coupling between said moveable electrode and said second conductive region comprises a low resistance contact.

8. The device of claim 3, wherein said fixed electrode is transparent to electromagnetic signals or waves.

9. The device of claim 8, wherein said moveable electrode impedes transmission of electromagnetic signals or waves.

10. The device of claim 4, wherein said potential is applied directly to said fixed and moveable electrodes.

11. A reconfigurable circuit comprising:

an array of actuatable devices which are addressed individually or in selected groups, each of said actuatable devices including;

a fixed electrode formed on a substrate, said fixed electrode including a transparent, high resistance layer; and

a moveable electrode formed with an anisotropic stress in a predetermined direction and disposed adjacent said fixed electrode.

12. The circuit of claim 11, wherein said circuit comprises a variable output power amplifier.

13. The circuit of claim 11, wherein each of said actuatable devices comprises a first and second electrically conductive regions which are isolated from one another by said fixed electrode, said moveable electrode being electrically coupled to said first conductive region.

14. The circuit of claim 13, wherein said moveable electrode moves to cover said fixed electrode and to electrically couple to said second conductive region, thus electrically coupling said first and second conductive regions, in response to a potential being applied across said fixed and moveable electrodes.

15. The circuit of claim 14, wherein said fixed electrode is transparent to electromagnetic signals or waves.

16. The circuit of claim 15, wherein said moveable electrode impedes transmission of electromagnetic signals or waves.

17. The circuit of claim 11, wherein said circuit comprises a tunable RF filter.

18. The circuit of claim 11, wherein said circuit comprises a microwave tuning element.

19. The circuit of claim 11, wherein said circuit comprises a variable resistor.

20. The circuit of claim 11, wherein said circuit comprises a variable capacitor.

21. The circuit of claim 11, wherein said circuit comprises a variable spiral inductor.

22. The circuit of claim 11, wherein said circuit comprises a MMIC with variable interconnects.

23. The circuit of claim 11, wherein said circuit comprises a binary switched circuit.