MICROELECTROMECHANICAL DEVICE WITH OPTICAL FUNCTION SEPARATED FROM MECHANICAL AND ELECTRICAL FUNCTION

• US 20080013145A1
• Filed: 07/02/2007
• Published: 01/17/2008
• Est. Priority Date: 09/27/2004
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: IDC, LLC
• Inventors: Chui, Clarence, Cummings, William, Kogut, Lior, Chiang, Chih-Wei, Tung, Ming-Hau, Gally, Brian, Tung, Yeh-Jiun, Endisch, Denis
• Granted Patent: US 7,944,599 B2
• Time in Patent Office: Days
• US Class Current: 359/224
• CPC Class Codes: B81B 2201/047 Optical MEMS not provided for in B81B2201/042 - B81B2201/045
• CPC Class Codes: B81B 3/0051 For defining the movement, i.e. structures that guide or limit the movement of an element mechanical arrangements for preventing or damping vibration or shock H01H3/60
• 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: G02B 26/023 comprising movable attenuating elements, e.g. neutral density filters
• CPC Class Codes: G02B 26/08 for controlling the direction of light in light guides G02B6/35
• CPC Class Codes: G02F 1/0128 based on electro-mechanical, magneto-mechanical, elasto-optic effects
• CPC Class Codes: G02F 1/133621 providing coloured light G02F1/133617, G02F1/133533 take precedence
• CPC Class Codes: G02F 1/29 for the control of the position or the direction of light beams, i.e. deflection
• CPC Class Codes: G09G 3/3466 based on interferometric effect
• CPC Class Codes: G09G 3/3696 Generation of voltages supplied to electrode drivers
• CPC Class Codes: Y10T 29/42 Piezoelectric device making

Abstract

A microelectromechanical (MEMS) device includes a substrate, a movable element over the substrate, and an actuation electrode above the movable element. The movable element includes a deformable layer and a reflective element. The deformable layer is spaced from the reflective element.

Claims

1. A microelectromechanical (MEMS) device comprising:

a substrate;

a movable element over the substrate, the movable element comprising a deformable layer and a reflective element, the deformable layer spaced from the reflective element; and

an actuation electrode above the movable element.

2. The MEMS device of claim 1, further comprising an optical layer, wherein light incident on the reflective element is reflected from the reflective element, the incident light and the reflected light propagating through the optical layer and not propagating through the actuation electrode.

3. The MEMS device of claim 2, wherein the substrate comprises the optical layer.

4. The MEMS device of claim 1, wherein a top surface of the substrate is spaced from the reflective element when no voltage is applied to the actuation electrode.

5. The MEMS device of claim 1, wherein a top surface of the substrate is in contact with the reflective element when no voltage is applied to the actuation electrode.

6. The MEMS device of claim 1, further comprising a second actuation electrode between the deformable layer and the reflective element.

7. The MEMS device of claim 6, wherein the movable element is responsive to voltages applied to the actuation electrode above the movable 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.

8. The MEMS device of claim 1, wherein the substrate comprises a second actuation electrode.

9. The MEMS device of claim 1, wherein a stationary element acts as a stop for movement of the movable element, the stationary element between the deformable layer and the reflective element.

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. A microelectromechanical (MEMS) device comprising:

means for moving a portion of the device, the moving means comprising means for deforming and means for reflecting, the deforming means spaced from the reflecting means;

means for supporting moving means; and

means for actuating the moving means, the actuating means above the moving means.

17. The MEMS device of claim 16, wherein the supporting means comprises a substrate.

18. The MEMS device of claim 16, wherein the moving means comprises a movable element.

19. The MEMS device of claim 16, wherein the deforming means comprises a deformable layer.

20. The MEMS device of claim 16, wherein the reflective means comprises a reflective element.

21. The MEMS device of claim 16, wherein the actuating means comprises an actuation electrode.

22. A method of manufacturing a microelectromechanical (MEMS) device, the method comprising:

forming a first sacrificial layer over a substrate;

forming a reflective element over the first sacrificial layer;

forming a second sacrificial layer over the reflective element;

forming a deformable layer over the second sacrificial layer, the deformable layer mechanically coupled to the reflective element;

forming a third sacrificial layer over the deformable layer;

forming an actuation electrode over the third sacrificial layer; and

removing the first, second, and third sacrificial layers.

23. The method of claim 22, further comprising forming an optical layer on the substrate before forming the first sacrificial layer.

24. The method of claim 22, wherein after removing the first, second, and third sacrificial materials, the reflective element is spaced from the substrate when no voltage is applied to the actuation electrode.

25. The method of claim 22, further comprising biasing the deformable layer, wherein after removing the first, second, and third sacrificial materials, the reflective element contacts the substrate when no voltage is applied to the actuation electrode.

26. A MEMS device fabricated by the method of claim 22.

27. A method of modulating light, the method comprising:

providing a display element comprising a substrate, a movable element over the substrate, and an actuation electrode, the movable element comprising a deformable layer and a reflective element, the deformable layer spaced from the reflective element, the actuation electrode above the movable element; and

applying a voltage to the actuation electrode, the voltage generating an attractive force on the movable element, thereby causing the movable element to move away from the substrate.