Microelectromechanical device and method utilizing conducting layers separated by stops

• US 7,742,220 B2
• Filed: 03/28/2007
• Issued: 06/22/2010
• Est. Priority Date: 03/28/2007
• Status: Expired due to Fees

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Kogut, Lior, Tung, Ming-Hau
• Primary Examiner(s): Mack; Ricky L
• Assistant Examiner(s): Tra; Tuyen Q
• Application Number:
  US11/692,734
• Publication Number:
  US 20080239455A1
• Time in Patent Office: 1,182 Days
• Field of Search: 359/290, 359/291, 359/293, 359/295, 359/298, 359/220, 359/222, 359/223, 359/224, 359/320, 359/323, 359/324, 359/245, 359/254
• US Class Current: 359/292
• CPC Class Codes: B81B 2201/047 Optical MEMS not provided for in B81B2201/042 - B81B2201/045
• CPC Class Codes: B81B 3/001 Structures having a reduced contact area, e.g. with bumps or with a textured surface
• 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 26/0841 the reflecting element being moved or deformed by electrostatic means
• CPC Class Codes: Y10T 29/49002 Electrical device making

Abstract

A microelectromechanical system (MEMS) device includes a reflective element that includes at least one stop member. The device also includes an electrode and an aperture that extends at least partially through the electrode. The aperture has a boundary. The device has an electrically nonconductive surface within the aperture or on a portion of the boundary of the aperture. A support structure separates the reflective element from the electrode. The reflective element can be moved between a first position and a second position. The stop member is spaced from the electrically nonconductive surface when the reflective element is in the first position. A portion of the stop member is in contact with the electrically nonconductive surface when the reflective element is in the second position. The reflective element and the electrode are electrically isolated from each other when the reflective element is in the second position.

Claims

1. An electromechanical device comprising:

a substrate;

a partially transparent or translucent and partially reflective electrode disposed over the substrate;

at least one aperture in the electrode extending at least partially through the electrode and having a boundary;

a reflective element comprising at least one stop member, wherein the electrode is disposed between the reflective element and the substrate, and wherein the at least one stop member extends toward one of the at least one aperture in the electrode;

an electrically nonconductive surface within the aperture or on a portion of the boundary; and

a support structure separating the reflective element from the electrode;

wherein the reflective element is configured to be movable between a first position and a second position, the stop member spaced from the electrically nonconductive surface when the reflective element is in the first position, and a portion of the stop member in contact with the electrically nonconductive surface when the reflective element is in the second position to stop the reflective element from contacting the electrically nonconductive surface except at the stop member portion of the reflective element and to electrically isolate the reflective element from the electrode when the reflective element is in the second position.

2. The device of claim 1, wherein the reflective element and the stop member are electrically conductive.

3. The device of claim 1, wherein the portion of the stop member has a width in a range from about 0.1 μ

m to about 4 μ

m.

4. The device of claim 1, wherein when the reflective element is in the second position, a gap between the electrode and the portion of the stop member is in a range from about 0.5 μ

m to about 2 μ

m.

5. The device of claim 1, wherein the aperture has a width in a range from about 0.1 μ

m to about 6 μ

m.

6. The device of claim 1, wherein a portion of the electrode is covered with a partially reflective layer.

7. The device of claim 1, wherein a portion of the electrode is covered with a passivation layer.

8. The device of claim 1, wherein the reflective element comprises a reflective surface facing toward the electrode and the stop member comprises a stop surface facing toward the electrically nonconductive surface, the stop surface positioned closer to the electrically nonconductive surface than is the reflective surface.

9. The device of claim 8, wherein the stop member extends toward the aperture by a length in a range from about 500 Å

to about 2000 Å

.

10. The device of claim 1, wherein at least one aperture extends completely through the electrode to expose the electrically nonconductive surface.

11. The device of claim 1, wherein the electrically nonconductive surface of the aperture comprises a portion of the substrate.

12. The device of claim 11, wherein the substrate comprises a dielectric material.

13. The device of claim 1, wherein the reflective element comprises at least a first stop member and a second stop member, and the device comprises at least a first aperture and a second aperture, the first aperture extending at least partially through the electrode and having a first boundary and the second aperture extending at least partially through the electrode and having a second boundary, the device further comprising a first electrically nonconductive surface within the first aperture or on a first portion of the first boundary and a second electrically nonconductive surface within the second aperture or on a second portion of the second boundary, and wherein, when the reflective element is in the second position, at least a first portion of the first stop member is in contact with the first electrically nonconductive surface and at least a second portion of the second stop member is in contact with the second electrically nonconductive surface.

14. The device of claim 1, wherein the support structure comprises a mechanical layer and wherein the reflective element comprises a portion of the mechanical layer.

15. The device of claim 1, wherein the support structure comprises a mechanical layer and wherein the reflective element is mechanically coupled to the mechanical layer.

16. The device of claim 1, wherein the support structure comprises a plurality of posts.

17. The 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.

18. The device of claim 17, further comprising a driver circuit configured to send at least one signal to said display.

19. The device of claim 18, further comprising a controller configured to send at least a portion of said image data to said driver circuit.

20. The device of claim 17, further comprising an image source module configured to send said image data to said processor.

21. The device of claim 20, wherein said image source module comprises at least one of a receiver, transceiver, and transmitter.

22. The device of claim 17, further comprising an input device configured to receive input data and to communicate said input data to said processor.

23. An electromechanical device comprising:

a substrate;

means for reflecting light, the reflecting means comprising at least one means for stopping movement of the reflecting means;

means for conducting electricity, the conducting means partially transparent or translucent and partially reflective, the conducting means disposed over the substrate;

means for receiving the at least one stopping means, the receiving means having a boundary, the receiving means having an electrically nonconductive portion within the receiving means or on the boundary; and

means for separating the reflecting means and the conducting means, the conducting means disposed between the reflecting means and the substrate,

wherein the reflecting means is configured to be movable between a first position and a second position, the stopping means spaced from the electrically nonconductive portion when the reflecting means is in the first position, and a portion of the stopping means in contact with the electrically nonconductive portion when the reflecting means is in the second position to stop the reflecting means from contacting the electrically nonconductive portion except at the stopping means portion of the reflecting means and to electrically isolate the reflecting means from the conducting means when the reflecting means is in the second position.

24. The device of claim 23, wherein the reflecting means comprises a reflective element.

25. The device of claim 23, wherein the stopping means comprises at least one stop member.

26. The device of claim 23, wherein the reflecting means comprises a surface facing toward the conducting means and the stopping means comprises one or more portions of the surface facing toward the electrically nonconductive portion, the stopping means extending toward the receiving means wherein at least a portion of the stopping means is closer to the electrically nonconductive portion than is the reflecting means.

27. The device of claim 23, wherein the conducting means comprises an electrode.

28. The device of claim 27, wherein the receiving means comprises at least one aperture extending at least partially through the electrode.

29. The device of claim 28, wherein the electrically nonconductive portion of the receiving means comprises an electrically nonconductive surface within the aperture or on a portion of the boundary.

30. The device of claim 23, wherein the separating means comprises a support structure.

31. The device of claim 30, wherein the support structure comprises a mechanical layer and one or more posts.