MEMS devices having overlying support structures

• US 8,120,125 B2
• Filed: 01/24/2011
• Issued: 02/21/2012
• Est. Priority Date: 07/22/2005
• Status: Expired due to Fees

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Sasagawa, Teruo, Ganti, SuryaPrakash, Miles, Mark W., Chui, Clarence, Kothari, Manish, Tung, Ming-Hau
• Primary Examiner(s): LE, DUNG ANH
• Application Number:
  US13/012,538
• Publication Number:
  US 20110115762A1
• Time in Patent Office: 393 Days
• Field of Search: 257414-412, 257/190, 257/528, 359/94, 359/224
• US Class Current: 257/420
• CPC Class Codes: B81B 2201/047 Optical MEMS not provided for in B81B2201/042 - B81B2201/045
• CPC Class Codes: B81B 2203/0307 Anchors
• CPC Class Codes: B81B 2203/053 Translation according to an axis perpendicular to the substrate
• CPC Class Codes: B81B 3/007 For controlling stiffness, e.g. ribs
• 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

Abstract

Embodiments of MEMS devices comprise a conductive movable layer spaced apart from a conductive fixed layer by a gap, and supported by rigid support structures, or rivets, overlying depressions in the conductive movable layer, or by posts underlying depressions in the conductive movable layer. In certain embodiments, portions of the rivet structures extend through the movable layer and contact underlying layers. In other embodiments, the material used to form the rigid support structures may also be used to passivate otherwise exposed electrical leads in electrical connection with the MEMS devices, protecting the electrical leads from damage or other interference.

Claims

1. An electromechanical device, comprising:

a substrate;

an electrode layer located over the substrate;

a conductive movable layer located over the electrode layer, wherein the movable layer is generally spaced apart from the electrode layer by an air gap, and wherein the movable layer includes depressions in support regions; and

rigid support structures formed over the movable layer and at least partially within the depressions in the movable layer, wherein the rigid support structures extend over only a portion of the movable layer, and wherein a portion of the movable layer located between rigid support structures is movable to bring said portion into contact with an underlying layer.

2. The device of claim 1, wherein the portion of the conductive movable layer located between rigid support structures collapses flat against underlying layers in response to electrostatic potential generated between the movable layer and the electrode layer.

3. The device of claim 1, wherein the movable layer includes a mechanical sublayer and a reflective sublayer.

4. The device of claim 3 wherein the mechanical sublayer is located over the reflective sublayer.

5. The device of claim 1, additionally comprising a dielectric layer located over the electrode layer.

6. The device of claim 1, wherein the MEMS device comprises an interferometric modulator.

7. The device of claim 1, additionally comprising:

a processor that is configured to communicate with at least one of said electrode layer and said movable layer, said processor being configured to process image data; and

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

8. The device of claim 7, further comprising a driver circuit configured to send at least one signal to at least one of said electrode layer and said movable layer.

9. The device of claim 8, further comprising a controller configured to send at least a portion of the image data to the driver circuit.

10. The device of claim 7, further comprising an image source module configured to send said image data to said processor.

11. The device of claim 10, wherein the image source module comprises at least one of a receiver, transceiver, and transmitter.

12. The device of claim 7, further comprising an input device configured to receive input data and to communicate said input data to said processor.

13. An electromechanical device, comprising:

an electrode layer supported by a substrate;

a conductive movable layer; and

means for supporting said conductive movable layer over said electrode layer, wherein said supporting means overlie only a portion of the conductive movable layer adjacent the means for supporting, and wherein a portion of said conductive movable layer located between said supporting means is movable to bring said portion into contact with an underlying layer.

14. The device of claim 13, wherein the supporting means comprise support structures formed over the second conducting means and at least partially within depressions in said second conducting means.

15. The device of claim 14, wherein the rigid support structures extend outside the depressions over an upper surface of the movable layer.