ELECTROMECHANICAL DISPLAY DEVICES AND METHODS OF FABRICATING THE SAME

• US 20110157010A1
• Filed: 03/07/2011
• Published: 06/30/2011
• Est. Priority Date: 07/25/2007
• Status: Abandoned Application

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Kothari, Manish, Ganti, Surya Prakash, Bos, Jan, Chang, Hung-Ta
• Application Number:
  US13/042,100
• Publication Number:
  US 20110157010A1
• Time in Patent Office: Days
• US Class Current: 345/156
• 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

MEMS devices include materials which are used in LCD or OLED fabrication to facilitate fabrication on the same manufacturing systems. Where possible, the same or similar materials are used for multiple layers in the MEMS device, and use of transparent conductors for partially transparent electrodes can be avoided to minimize the number of materials needed and minimize fabrication costs. Certain layers comprise alloys selected to achieve desired properties. Intermediate treatment of deposited layers during the manufacturing process can be used to provide layers having desired properties.

Claims

1. An electromechanical device, comprising:

a conductive optical absorber formed over a substrate and patterned to form strip electrodes, wherein the optical absorber serves as the primary conductor in said strip electrodes within optically active areas of the electromechanical device;

at least one support structure formed over the optical absorber; and

a conductive deformable layer formed over the at least one support structure and spaced apart from the conductive optical absorber, wherein the deformable layer is electrostatically deflectable towards the optical absorber within said optically active areas of the electromechanical device.

3. The electromechanical device of claim 1, wherein the optical absorber reflects between about 28.5% and 34.5% of incident visible light.

4. The electromechanical device of claim 1, additionally comprising a blackmask absorber layer underlying at least a portion of the optical absorber, wherein the blackmask absorber comprises the same material as the optical absorber.

5. The electromechanical device of claim 4, wherein the blackmask absorber is located in optically inactive areas of the display.

6. The electromechanical device of claim 4, wherein at least a portion of the blackmask absorber layer underlies a portion of said at least one support structure.

7. The electromechanical device of claim 1, additionally comprising an optical dielectric layer located over at least a portion of the optical absorber, wherein the optical absorber comprises the only conductive material located between the optical dielectric layer and the substrate in the optically active areas of the display.

8. The electromechanical device of claim 1, where the electromechanical device does not comprise ITO in an optically active area of the display.

9. The electromechanical device of claim 1, wherein the electromechanical device functions as an interferometric modulator.

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

a processor that is configured to communicate with at least one of the conductive optical absorber and the conductive deformable layer, the processor being configured to process image data; and

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

11. The electromechanical device of claim 10, further comprising a driver circuit configured to send at least one signal to at least one of the conductive optical absorber and the conductive deformable layer.

12. The electromechanical 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 electromechanical device of claim 10, further comprising an image source module configured to send the image data to the processor.

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

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

2. The electromechanical device of claim 2, wherein the optical absorber has a thickness of about 70-75 angstroms.

16. A method of fabricating an electromechanical device, comprising:

forming a conductive optical absorber over a substrate;

patterning the conductive optical absorber to form strip electrodes, wherein the optical absorber functions as the primary conductor in said strip electrodes in optically active regions of the electromechanical device;

forming a sacrificial layer over the optical absorber;

forming at least one support structure over the optical absorber;

forming a conductive deformable layer over the sacrificial layer and the at least one support structure; and

performing a release etch to remove the sacrificial layer, forming a cavity between the deformable layer and the optical absorber.

17. The method of claim 16, additionally comprising forming a blackmask absorber layer prior to deposition of the optical absorber, wherein the blackmask absorber comprises the same material as the optical absorber.

18. The method of claim 17, additionally comprising patterning the blackmask absorber layer to remove the blackmask absorber layer in optically active areas of the electromechanical device.

19. The method of claim 17, wherein the sacrificial layer comprises the same material as the optical absorber and blackmask absorber.

20. The method of claim 16, additionally comprising forming a bussing structure in electrical communication with the optical absorber.

21. The method of claim 20, wherein forming the bussing structure comprises:

forming a first bussing sublayer;

exposing the first bussing sublayer to vacuum for a period of time; and

forming a second bussing sublayer over the first layer after exposing the first bussing sublayer to vacuum.

22. An electromechanical device, comprising:

means for absorbing at least a portion of incident light, wherein the absorbing means serves as the primary conductor in said strip electrodes within optically active areas of the electromechanical device;

at least one support structure formed over the optical absorber; and

conductive deformable layer formed over the at least one support structure and spaced apart from the absorbing means, wherein the deformable layer is electrostatically deflectable towards the absorbing means within said optically active areas of the electromechanical device.

23. The electromechanical device of claim 22, wherein the absorbing means comprises a conductive optical absorber.

24. The electromechanical device of claim 23, wherein the optical absorber reflects between about 28.5% and 34.5% of incident visible light.