Methods for manufacturing fluid-filled MEMS displays

• US 9,176,318 B2
• Filed: 10/19/2007
• Issued: 11/03/2015
• Est. Priority Date: 05/18/2007
• Status: Expired due to Fees

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Pixtronix, Incorporated (Qualcomm, Inc.)
• Inventors: Hagood, Nesbitt W., Steyn, Jasper Lodewyk, Fijol, John J.
• Primary Examiner(s): KENNEDY, TIMOTHY J
• Application Number:
  US11/975,411
• Publication Number:
  US 20080283175A1
• Time in Patent Office: 2,937 Days
• Field of Search: 156/99, 156/145, 156/156, 156/285, 264/272.11, 264/272.12, 264/272.13, 264/272.14, 264/272.16, 264/272.17, 264/272.19, 264/272.2
• US Class Current: 1/1
• CPC Class Codes: G02B 26/0833 the reflecting element being a micromechanical device, e.g. a MEMS mirror, DMD G02B26/0825 takes precedence; micromechanical devices in general B81B

Abstract

This invention relates to methods of manufacturing fluid-filled MEMS displays, where the fluid is sealed in the display assembly and substantially surrounds the moving components of the display to reduce the effects of stiction and to improve the optical and electromechanical performance of the display.

Claims

1. A method for manufacturing a display assembly including first and second transparent substrates comprising:

providing an array of MEMS light modulators on the first transparent substrate;

providing a plurality of spacers on at least one of the transparent substrates, the plurality of spacers being dispersed among the array of MEMS light modulators;

positioning the second transparent substrate adjacent to the first substrate such that the first transparent substrate is separated from the second transparent substrate by a gap maintained by the plurality of spacers;

applying a curable seal material along a majority of a perimeter of the display assembly to create a perimeter seal that defines a cavity;

subsequent to applying the curable seal material along the majority of the perimeter, filling the cavity with a fluid such that the fluid substantially surrounds the movable portions of the MEMS light modulators;

subsequent to filling the cavity with fluid, partially curing the curable seal material along at least a portion of the perimeter of the display assembly; and

further curing the partially cured seal material of the perimeter seal in a separate curing step subsequent to partially curing the curable seal material.

2. The method of claim 1 wherein the fluid is a liquid.

3. The method of claim 1 wherein the fluid is a gas.

4. The method of claim 1 wherein the fluid is a lubricant.

5. The method of claim 1 wherein aligning of the first and second transparent substrates is performed prior to the partial curing of the curable seal material.

6. The method of claim 2 wherein filling the display assembly with fluid comprises applying the liquid to one of the first and second transparent substrates prior to aligning the first and second transparent substrates.

7. The method of claim 1 wherein filling the display assembly with fluid comprises reducing the air pressure surrounding the display assembly to below atmospheric pressure.

8. The method of claim 1 further comprising, while fabricating the array of MEMS lights modulators, fabricating at least one additional array of MEMS light modulators on the first transparent substrate.

9. The method of claim 8 further comprising separating the array of MEMS light modulators from the at least one additional array of MEMS light modulators subsequent to applying the curable seal material.

10. The method of claim 1 further comprising fabricating spacers on at least one of the first and second transparent substrates to maintain a gap between the two substrates.

11. The method of claim 1 further comprising providing a conductive material which bridges the gap between the first and second transparent substrates.

24. The method of claim 1, wherein the fluid completely fills the cavity.

25. The method of claim 1, wherein the curable seal material includes a polymer.

27. The method of claim 1, further comprising applying pressure to the first and second substrates while curing the curable seal material.

28. The method of claim 1, wherein the partial curing of the curable seal material occurs during an alignment of the first and second substrates.

29. The method of claim 1, wherein the partial curing of the curable seal material occurs while the first and second substrates are held in an alignment apparatus.

30. The method of claim 29, wherein the alignment apparatus comprises at least one of a motor and a camera.

35. The method of claim 1, further comprising aligning the first transparent substrate with the second transparent substrate based on a position of at least one of the plurality of spacers.

12. A method for manufacturing a display assembly including first and second transparent substrates comprising:

providing an array of MEMS light modulators on the first transparent substrate;

providing a plurality of spacers on at least one of the transparent substrates, the plurality of spacers being dispersed among the array of MEMS light modulators;

positioning the second transparent substrate adjacent to the first substrate such that the first transparent substrate is separated from the second transparent substrate by a gap maintained by the plurality of spacers;

applying a curable seal material along at least a portion of a perimeter of the display assembly;

subsequent to applying the curable seal material, partially curing the seal material along at least a portion of the perimeter of the display assembly;

subsequent to partially curing the substrate seal material, further curing the curable seal material in a separate curing step to couple the first and second transparent substrates; and

filling the display assembly with a fluid subsequent to the further curing of the curable seal material such that the fluid substantially surrounds the movable portions of the MEMS light modulators.

13. The method of claim 12 wherein the fluid is a liquid.

14. The method of claim 12 wherein the fluid is a gas.

15. The method of claim 12 wherein the fluid is a lubricant.

16. The method of claim 12 wherein aligning of the first and second transparent substrates is performed prior to the partial curing of the curable seal material.

17. The method of claim 12 further comprising, while fabricating the array of MEMS lights modulators, fabricating at least one additional array of MEMS light modulators on the first transparent substrate.

18. The method of claim 17 further comprising separating the array of MEMS light modulators from the at least one additional array of MEMS light modulators subsequent to applying the curable seal material.

19. The method of claim 12 further comprising fabricating spacers on at least one of the first and second transparent substrates to maintain a gap between the two substrates.

20. The method of claim 12 further comprising providing a conductive material which bridges the gap between the first and second transparent substrates.

21. The method of claim 12 wherein applying the curable seal material to the display assembly comprises leaving at least one filling hole unsealed.

22. The method of claim 12 wherein filling the display assembly comprises reducing the air pressure surrounding the display assembly to below atmospheric pressure.

23. The method of claim 21 further comprising sealing the at least one filling hole subsequent to filling the display assembly to contain the fluid in the display assembly.

26. The method of claim 12, wherein the curable seal material includes a polymer.

31. The method of claim 12, further comprising applying pressure to the first and second substrates while curing the curable seal material.

32. The method of claim 12, wherein the partial curing of the curable seal material occurs prior to an alignment of the first and second substrates.

33. The method of claim 12, wherein the partial curing of the curable seal material occurs while the first and second substrates are held in an alignment apparatus.

34. The method of claim 33, wherein the alignment apparatus comprises at least one of a motor and a camera.

36. The method of claim 12, further comprising aligning the first transparent substrate with the second transparent substrate based on a position of at least one of the plurality of spacers.