Microelectromechanical device with optical function separated from mechanical and electrical function

• US 7,612,932 B2
• Filed: 07/02/2007
• Issued: 11/03/2009
• Est. Priority Date: 09/27/2004
• Status: Expired due to Fees

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: IDC, LLC
• Inventors: Chui, Clarence, Kogut, Lior, Chiang, Chih-Wei, Tung, Ming-Hau, Tung, Yeh-Jiun, Endisch, Denis
• Primary Examiner(s): Choi; William C
• Application Number:
  US11/772,730
• Publication Number:
  US 20080013144A1
• Time in Patent Office: 855 Days
• Field of Search: 359/198, 359/224, 359/290, 359/295
• US Class Current: 359/290
• CPC Class Codes: B81B 2201/042 Micromirrors, not used as optical switches
• CPC Class Codes: B81B 3/0086 Electrical characteristics, e.g. reducing driving voltage, improving resistance to peak voltage
• CPC Class Codes: G02B 26/001 based on interference in an adjustable optical cavity interference filters G02B5/28; devices or arrangements using multiple reflections in spectrometry or monochromators G01J3/26
• CPC Class Codes: Y10T 29/42 Piezoelectric device making

Abstract

A microelectromechanical (MEMS) device includes a first reflective layer, a movable element, and an actuation electrode. The movable element is over the first reflective layer. The movable element includes a deformable layer and a reflective element. The actuation electrode is between the deformable layer and the reflective element.

Claims

1. A microelectromechanical (MEMS) device comprising:

a first reflective layer;

a movable element over the first reflective layer, the movable element comprising a deformable layer and a reflective element; and

an actuation electrode between the deformable layer and the reflective element, wherein a voltage applied to the actuation electrode generates a first attractive force in a first direction on a first portion of the movable element and generates a second attractive force in a second direction on a second portion of the movable element, the second direction substantially opposite the first direction, the first attractive force greater than the second attractive force, the movable element responsive to the first and second attractive forces by moving generally in the first direction.

2. The MEMS device of claim 1, wherein the first portion of the movable element comprises the deformable layer.

3. The MEMS device of claim 1, wherein the first portion of the movable element comprises the reflective element.

4. The MEMS device of claim 1, wherein a distance between the actuation electrode and the second portion of the movable element is greater than a distance between the actuation electrode and the first portion of the movable element.

5. The MEMS device of claim 1, wherein a distance between the actuation electrode and the second portion of the movable element is at least about 10% greater than a distance between the actuation electrode and the first portion of the movable element.

6. The MEMS device of claim 1, further comprising a conductive layer between the actuation electrode and the second portion.

7. The MEMS device of claim 1, further comprising a second actuation electrode.

8. The MEMS device of claim 7, wherein the movable element is responsive to voltages applied to the second actuation electrode by moving generally in the second direction.

9. The MEMS device of claim 1, wherein the first reflective layer is spaced from the reflective element when an actuation voltage is applied to the actuation electrode.

10. The MEMS device of claim 1, further comprising:

a display;

a processor that is configured to communicate with said display, said processor being configured to process image data; and

a memory device that is configured to communicate with said processor.

11. The MEMS device of claim 10, further comprising a driver circuit configured to send at least one signal to the display.

12. The MEMS device of claim 11, further comprising a controller configured to send at least a portion of the image data to the driver circuit.

13. The MEMS device of claim 10, further comprising an image source module configured to send said image data to said processor.

14. The MEMS device of claim 13, wherein the image source module comprises at least one of a receiver, transceiver, and transmitter.

15. The MEMS device of claim 10, further comprising an input device configured to receive input data and to communicate said input data to said processor.

16. The MEMS device of claim 1, wherein the first reflective layer is partially reflective and partially transparent.

17. A microelectromechanical (MEMS) device comprising:

a first reflective layer;

a movable element over the first reflective layer, the movable element comprising a deformable layer and a reflective element; and

an actuation electrode between the deformable layer and the reflective element, wherein a lower surface of the deformable layer contacts a stationary portion of the device when an actuation voltage is applied to the actuation electrode.

18. The MEMS device of claim 17, wherein a voltage applied to the actuation electrode generates a first attractive force in a first direction on a first portion of the movable element and generates a second attractive force in a second direction on a second portion of the movable element, the second direction substantially opposite the first direction, the first attractive force greater than the second attractive force, the movable element responsive to the first and second attractive forces by moving generally in the first direction.

19. The MEMS device of claim 18, wherein the first portion of the movable element comprises the deformable layer.

20. The MEMS device of claim 18, wherein a distance between the actuation electrode and the second portion of the movable element is greater than a distance between the actuation electrode and the first portion of the movable element.

21. The MEMS device of claim 18, wherein a distance between the actuation electrode and the second portion of the movable element is at least about 10% greater than a distance between the actuation electrode and the first portion of the movable element.

22. The MEMS device of claim 18, further comprising a conductive layer between the actuation electrode and the second portion.

23. The MEMS device of claim 17, further comprising a second actuation electrode.

24. The MEMS device of claim 23, wherein the movable element is responsive to voltages applied to the actuation electrode between the deformable layer and the reflective element by moving generally in a first direction and wherein the movable element is responsive to voltages applied to the second actuation electrode by moving generally in a second direction, the second direction substantially opposite the first direction.

25. The MEMS device of claim 17, wherein the first reflective layer is spaced from the reflective element when an actuation voltage is applied to the actuation electrode.

26. The MEMS device of claim 17, wherein the first reflective layer is partially reflective and partially transparent.

27. A microelectromechanical (MEMS) device comprising:

a first reflective layer;

a movable element over the first reflective layer, the movable element comprising a deformable layer and a reflective element; and

an actuation electrode between the deformable layer and the reflective element, wherein an upper surface of the reflective element contacts a stationary portion of the device when an actuation voltage is applied to the actuation electrode.

28. The MEMS device of claim 27, wherein a voltage applied to the actuation electrode generates a first attractive force in a first direction on a first portion of the movable element and generates a second attractive force in a second direction on a second portion of the movable element, the second direction substantially opposite the first direction, the first attractive force greater than the second attractive force, the movable element responsive to the first and second attractive forces by moving generally in the first direction.

29. The MEMS device of claim 28, wherein the first portion of the movable element comprises the reflective element.

30. The MEMS device of claim 28, wherein a distance between the actuation electrode and the second portion of the movable element is greater than a distance between the actuation electrode and the first portion of the movable element.

31. The MEMS device of claim 28, wherein a distance between the actuation electrode and the second portion of the movable element is at least about 10% greater than a distance between the actuation electrode and the first portion of the movable element.

32. The MEMS device of claim 28, further comprising a conductive layer between the actuation electrode and the second portion.

33. The MEMS device of claim 27, further comprising a second actuation electrode.

34. The MEMS device of claim 33, wherein the movable element is responsive to voltages applied to the actuation electrode between the deformable layer and the reflective element by moving generally in a first direction and wherein the movable element is responsive to voltages applied to the second actuation electrode by moving generally in a second direction, the second direction substantially opposite the first direction.

35. The MEMS device of claim 27, wherein the first reflective layer is spaced from the reflective element when an actuation voltage is applied to the actuation electrode.

36. The MEMS device of claim 27, wherein the first reflective layer is partially reflective and partially transparent.