Micro-mirror device including dielectrophoretic liquid

• US 20030202265A1
• Filed: 03/12/2003
• Published: 10/30/2003
• Est. Priority Date: 04/30/2002
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Reboa, Paul F., McMahon, Terry E., Shreeve, Robert W.
• Granted Patent: US 6,954,297 B2
• Time in Patent Office: Days
• US Class Current: 359/877
• CPC Class Codes: B81B 2201/042 Micromirrors, not used as optical switches
• CPC Class Codes: B81B 2203/0109 Bridges
• CPC Class Codes: B81B 7/04 Networks or arrays of similar microstructural devices
• CPC Class Codes: G02B 26/004 based on a displacement or a deformation of a fluid
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means
• CPC Class Codes: Y10S 359/904 Micromirror

Abstract

A micro-mirror device includes a substrate having a surface, and a plate spaced from and oriented substantially parallel to the surface of the substrate such that the plate and the surface of the substrate define a cavity therebetween. A dielectrophoretic liquid capable of movement when an electrical signal is applied to the micro-mirror device is disposed in the cavity, and a reflective element is interposed between the surface of the substrate and the plate such that the reflective element is adapted to move between a first position and at least one second position.

Claims

1. A micro-mirror device, comprising:

a substrate having a surface;

a plate spaced from and oriented substantially parallel to the surface of the substrate, the plate and the surface of the substrate defining a cavity therebetween;

a dielectrophoretic liquid disposed in the cavity, the dielectrophoretic liquid being capable of movement when an electrical signal is applied to the device; and

a reflective element interposed between the surface of the substrate and the plate,

wherein the reflective element is adapted to move between a first position and at least one second position.

2. A micro-mirror device according to claim 1, wherein the dielectrophoretic liquid is non-hydrogen bonding and has a dielectric constant of less than 20.

3. A micro-mirror device according to claim 1, wherein the dielectrophoretic liquid has a dipole moment of at least about 1 Debye.

4. A micro-mirror device according to claim 1, wherein the dielectrophoretic liquid is compressible.

5. A micro-mirror device according to claim 1, wherein the dielectrophoretic liquid is polarizable.

6. A micro-mirror device according to claim 1, wherein the dielectrophoretic liquid is substantially transparent.

7. A micro-mirror device according to claim 1, wherein the dielectrophoretic liquid is selected from the group consisting of poly(phenyl ether)_x wherein x is from about 2 to about 6, alkyls, alkenes and cyclic alkyls having from about 2 to about 12 carbon atoms, perfluoro-alkyls, 1,1-diphenylethylene and 1,2-diphenylethylene, benzene and substituted benzenes, chlorinated aromatics, polychlorinated biphenyls, and perfluoroethers.

8. A micro-mirror device according to claim 7, wherein the perfluoro-alkyl is perfluorodecahydronaphthalane, and the alkene is selected from dodecene and olive oil.

9. A micro-mirror device according to claim 1, wherein the liquid is selected from the group consisting of 1,1-diphenylethylene, 1,2-diphenylethylene, and mixtures thereof.

10. A micro-mirror device according to claim 1, wherein the dielectrophoretic liquid is a perfluoroether.

11. A micro-mirror device according to claim 1, wherein the reflective element is at least one of positioned above the dielectrophoretic liquid and submerged in the dielectrophoretic liquid.

12. A micro-mirror device according to claim 1, further comprising:

at least one electrode formed on the surface of the substrate, the electrode having differing dimensions from the reflective element,

wherein the reflective element is adapted to move in response to application of an electrical signal to the at least one electrode and the electrical signal is adapted to form a non-uniform electric field in the cavity.

13. A micro-mirror device according to claim 1, wherein the dielectrophoretic liquid is adapted to increase an actuation force on the reflective element as generated by a given activation energy.

14. A micro-mirror device according to claim 1, wherein the dielectrophoretic liquid is used to transfer heat within the micro-mirror device.

15. A display device including the micro-mirror device of claim 1.

16. A micro-mirror device, comprising:

a substrate having a surface;

a plate spaced from and oriented substantially parallel to the surface of the substrate, the plate and the surface of the substrate defining a cavity therebetween;

a liquid disposed in the cavity, the liquid being capable of movement without exhibiting outgassing when an electrical signal is applied to the device; and

a reflective element interposed between the surface of the substrate and the plate,

wherein the reflective element is adapted to move between a first position and at least one second position.

17. A micro-mirror device according to claim 16, wherein the liquid has a dielectric constant of less than 20.

18. A micro-mirror device according to claim 16, wherein the liquid is capable of movement without exhibiting Joule heating when an electrical signal is applied to the device.

19. A micro-actuator, comprising:

a substrate having a surface;

a plate spaced from and oriented substantially parallel to the surface of the substrate, the plate and the surface of the substrate defining a cavity therebetween;

a dielectrophoretic liquid disposed in the cavity and capable of movement when an electrical signal is applied to the micro-actuator; and

an actuating element interposed between the surface of the substrate and the plate,

wherein the actuating element is adapted to move between a first position and at least one second position.

20. A micro-actuator according to claim 19, wherein the dielectrophoretic liquid is non-hydrogen bonding and has a dielectric constant of less than 20.

21. A micro-actuator according to claim 19, wherein the dielectrophoretic liquid has a dipole moment of at least about 1 Debye.

22. A micro-actuator according to claim 19, wherein the dielectrophoretic liquid is compressible.

23. A micro-actuator according to claim 19, wherein the dielectrophoretic liquid is polarizable.

24. A micro-actuator according to claim 19, wherein the dielectrophoretic liquid is substantially transparent.

25. A micro-actuator according to claim 19, wherein the dielectrophoretic liquid is selected from the group consisting of poly(phenyl ether)_x wherein x is from about 2 to about 6, alkyls, alkenes and cyclic alkyls having from about 2 to about 12 carbon atoms, perfluoro-alkyls, 1,1-diphenylethylene and 1,2-diphenylethylene, benzene and substituted benzenes, chlorinated aromatics, polychlorinated biphenyls, and perfluoroethers.

26. A micro-actuator according to claim 19, wherein the dielectrophoretic liquid and the plate are substantially transparent.

27. A micro-actuator according to claim 19, wherein the actuating element is at least one of positioned above the dielectrophoretic liquid and submerged in the dielectrophoretic liquid.

28. A micro-actuator according to claim 19, further comprising:

at least one electrode formed on the surface of the substrate, the electrode having differing dimensions from the actuating element,

wherein the actuating element is adapted to move in response to application of an electrical signal to the at least one electrode and the electrical signal is adapted to form a non-uniform electric field in the cavity.

29. A micro-actuator according to claim 19, wherein the dielectrophoretic liquid is adapted to increase an actuation force on the actuating element as generated by a given activation energy.

30. A micro-actuator according to claim 19, wherein the dielectrophoretic liquid is used to transfer heat within the micro-actuator.

31. A method of using a dielectrophoretic liquid in a micro-actuator including an actuator element adapted to move between a first position and at least one second position, the method comprising:

disposing the dielectrophoretic liquid in a cavity of the micro-actuator, including at least one of positioning the actuator element above and submerging the actuator element in the dielectrophoretic liquid; and

moving the actuator element between the first position and the least one second position, including applying an electrical signal to the micro-actuator,

wherein the dielectrophoretic liquid exhibits movement when the electrical signal is applied to the micro-actuator and the movement contributes to the moving of the actuator element between the first position and the at least one second position.

32. A method of using a dielectrophoretic liquid according to claim 31, wherein the dielectrophoretic liquid is non-hydrogen-bonding and has a dielectric constant of less than 20.

33. A method of using a dielectrophoretic liquid according to claim 32, wherein the dielectrophoretic liquid has a dipole moment of at least about 1 Debye.

34. A method of using a dielectrophoretic liquid according to claim 32, wherein the dielectrophoretic liquid is compressible.

35. A method of using a dielectrophoretic liquid according to claim 32, wherein the dielectrophoretic liquid is polarizable.

36. A method of using a dielectrophoretic liquid according to claim 32, wherein the dielectrophoretic liquid is substantially transparent.

37. A method of using a dielectrophoretic liquid according to claim 32, wherein the dielectrophoretic liquid is selected from the group consisting of poly(phenyl ether)_x wherein x is from about 2 to about 6, alkyls, alkenes and cyclic alkyls having from about 2 to about 12 carbon atoms, perfluoro-alkyls, 1,1-diphenylethylene and 1,2-diphenylethylene, benzene and substituted benzenes, chlorinated aromatics, polychlorinated biphenyls, and perfluoroethers.

38. A method of using a dielectrophoretic liquid according to claim 37, wherein the perfluoro-alkyl is perfluorodecahydronaphthalane, and the alkene is selected from dodecene and olive oil.

39. A method of using a dielectrophoretic liquid according to claim 32, wherein the dielectrophoretic liquid is selected from the group consisting of 1,1-diphenylethylene, 1,2-diphenylethylene, and mixtures thereof.

40. A method of using a dielectrophoretic liquid according to claim 32, wherein the dielectrophoretic liquid is a perfluoroether.

41. A method of using a dielectrophoretic liquid according to claim 31, further comprising:

transferring heat within the micro-actuator with the dielectrophoretic liquid.