Display device with desiccant

• US 8,410,690 B2
• Filed: 02/13/2009
• Issued: 04/02/2013
• Est. Priority Date: 02/13/2009
• Status: Expired due to Fees

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Natarajan, Bangalore R., Gousev, Evgeni, Lavery, Kristopher A.
• Primary Examiner(s): HINES, ANNE M
• Application Number:
  US12/371,302
• Publication Number:
  US 20100206629A1
• Time in Patent Office: 1,509 Days
• Field of Search: 502/400, 502/405, 502/414, 502/416, 502/417, 313498-512
• US Class Current: 313/512
• CPC Class Codes: B01D 2253/108 Zeolites
• CPC Class Codes: B01D 53/261 by adsorption
• CPC Class Codes: B01D 53/28 Selection of materials for use as drying agents
• CPC Class Codes: B01J 20/18 Synthetic zeolitic molecular sieves
• CPC Class Codes: B01J 20/183 Physical conditioning without chemical treatment, e.g. drying, granulating, coating, irradiation
• CPC Class Codes: B01J 20/2803 Sorbents comprising a binder, e.g. for forming aggregated, agglomerated or granulated products
• CPC Class Codes: B01J 20/2808 being less than 2 nm, i.e. micropores or nanopores
• CPC Class Codes: B01J 2220/42 Materials comprising a mixture of inorganic materials materials coated or impregnated on a carrier B01J20/32
• CPC Class Codes: B81B 2201/047 Optical MEMS not provided for in B81B2201/042 - B81B2201/045
• CPC Class Codes: B81C 1/00285 using materials for controlling the level of pressure, contaminants or moisture inside of the package, e.g. getters
• CPC Class Codes: B81C 2201/112 Depositing an anti-stiction or passivation coating, e.g. on the elastic or moving parts
• CPC Class Codes: H01L 23/26 including materials for absorbing or reacting with moisture or other undesired substances , e.g. getters
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/09701 Low temperature co-fired ceramic [LTCC]
• CPC Class Codes: H01L 2924/12044 OLED
• CPC Class Codes: H01L 2924/1433 Application-specific integrated circuit [ASIC]
• CPC Class Codes: H10K 50/846 comprising getter material or desiccants
• CPC Class Codes: H10K 59/87 Passivation; Containers; Encapsulations
• CPC Class Codes: H10K 59/874 including getter material or desiccant
• CPC Class Codes: Y10T 156/10 : Methods of surface bonding and/or assembly therefor

Abstract

Systems and methods for providing MEMS devices with integrated desiccant are provided. In one embodiment, a dry composition comprising desiccant is impact sprayed onto the backplate or substrate of a MEMS device, and becomes fused with the substrate. In another embodiment, the desiccant is impact sprayed such that the desiccant adheres to the impact sprayed surface. In yet another embodiment, the impact-sprayed surface is impregnated with the desiccant. In still another embodiment, the desiccant is combined with a suitable inorganic binder, then impact sprayed such that the desiccant adheres to the impact sprayed surface. In yet a further embodiment, the desiccant is micronized or pulverized into a powder of desired particle size, and then impact sprayed onto a surface. Thus, the desiccant particles or powder are fused onto the target surface through the impact spraying process.

Claims

1. An electronic device package, comprising:

a first substrate supporting an electronic device;

a backplate cover sealed to the first substrate to enclose the electronic device within a package; and

an impact-sprayed desiccant fused onto at least a portion of the backplate cover or first substrate.

2. The device package of claim 1, wherein the impact-sprayed desiccant includes a substantially dry zeolite material.

3. The device package of claim 2, wherein the zeolite material has a pore size of approximately 3 angstroms.

4. The device package of claim 2, wherein the zeolite material has a pore size of between approximately 3 to 10 angstroms.

5. The device package of claim 1, wherein the backplate cover or first substrate includes a layer of impact-sprayed desiccant with a thickness between approximately 0.5 and 5.0 microns.

6. The device package of claim 1, wherein the impact-sprayed desiccant includes a first zeolite material having a pore size of approximately 3 angstroms and a second zeolite material having a pore size of between approximately 3 to 10 angstroms.

7. The device package of claim 6, wherein no less than approximately 60 percent of the impact-sprayed desiccant includes the first zeolite material.

8. The device package of claim 6, wherein the impact-sprayed desiccant includes between approximately 10 percent to 40 percent of the second zeolite material.

9. The device package of claim 6, wherein between approximately 60 percent to 80 percent of the impact-sprayed desiccant includes the first zeolite material, wherein between approximately 20 percent to 40 percent of the impact-sprayed desiccant includes the second zeolite material, and wherein the second zeolite material has a pore size of approximately 10 angstroms.

10. The device package of claim 9, wherein the second zeolite material includes at least one of a fluorinated surfactant, a silane, a chlorosilane, or a functionalized hydrocarbon.

11. The device package of claim 1, wherein the impact-sprayed desiccant includes between approximately 40 percent to 90 percent dry zeolite material and between approximately 10 percent and 60 percent dry inorganic binder.

12. The device package of claim 11, wherein the inorganic binder includes at least one of bentonite, silicate, magnesium oxide, and inorganic clay.

13. The device package of claim 1, wherein the impact-sprayed desiccant includes at least one of zeolite, molecular sieves, surface adsorbents, bulk adsorbents, and chemical reactants.

14. The device package of claim 1, wherein the impact-sprayed desiccant includes at least one of an inorganic oxide, a metal, and a phosphor.

15. The device package of claim 1, wherein the electronic device includes a display device.

16. The device package of claim 1, wherein the electronic device includes a MEMS device.

17. The device package of claim 1, wherein the display device includes an organic light emitting diode (OLED) device.

18. The device package of claim 1, wherein the display device includes an interferometric modulator display device.

19. The device package of claim 1, further comprising:

a display;

a processor that is configured to communicate with the display, said processor being configured to process image data; and

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

20. The device package of claim 19, further comprising:

a driver circuit configured to send at least one signal to the display.

21. The device package of claim 20, further comprising:

a controller configured to send at least a portion of said image data to said driver circuit.

22. The device package of claim 19, further comprising:

an image source module configured to send said image data to said processor.

23. The device package of claim 22, wherein said image source module includes at least one of a receiver, transceiver, and transmitter.

24. The device package of claim 19, further comprising:

an input device configured to receive input data and to communicate said input data to said processor.

25. The device package of claim 1, wherein the at least a portion of the backplate cover or first substrate in contact with the impact-sprayed desiccant includes a roughened surface.

26. The device package of claim 25, wherein the roughened surface is the result of impact spraying the desiccant onto the at least a portion of the backplate cover or first substrate.

27. The device package of claim 1, wherein the at least a portion of the backplate cover or first substrate in contact with the impact-sprayed desiccant includes an etched surface.

28. The device package of claim 1, wherein the at least a portion of the backplate cover or first substrate is impregnated with the impact-sprayed desiccant.

29. A method of manufacturing an electronic device, comprising:

providing a first substrate supporting an electronic device;

providing a backplate cover;

impact spraying a desiccant to fuse the desiccant onto at least a portion of the backplate cover or first substrate; and

joining the backplate cover to the first substrate to form a package enclosing the electronic device.

30. The method of claim 29, wherein the desiccant includes a substantially dry zeolite material.

31. The method of claim 29, further comprising providing a mask on the backplate cover for selectively impact spraying a portion of the backplate cover with the desiccant.

32. The method of claim 29, wherein impact spraying the desiccant includes impact spraying the desiccant onto at least a portion of the backplate cover or the first substrate with a thickness between approximately 0.5 and 5.0 microns.

33. The method of claim 29, wherein the electronic device includes a MEMS device.

34. The method of claim 29, wherein the electronic device includes an interferometric modulator (IMOD) array.

35. The method of claim 29, wherein the electronic device includes an organic light emitting diode (OLED) device.

36. The method of claim 29, wherein the electronic device includes a cellular telephone.

37. The method of claim 29, wherein the electronic device includes a display device.

38. An electronic display, comprising:

means for supporting a display device;

means for covering the display device joined to the supporting means to form a package enclosing the display device; and

means for desiccating the package, wherein the desiccating means includes impact-sprayed desiccant that is fused onto the covering means.

39. The electronic display of claim 38, wherein the supporting means includes a transparent substrate.

40. The electronic display of claim 38, wherein the covering means includes a backplate.

41. The electronic display of claim 38, wherein the impact-sprayed desiccant includes zeolite.

42. A surface including impact-sprayed desiccant fused onto at least a portion of the surface.

43. The surface of claim 42, wherein the surface is sealed to a second surface to form a package, and wherein the impact-sprayed desiccant is fused to the surface inside the package.

44. The surface of claim 42, wherein the impact-sprayed desiccant is zeolite.

45. The surface of claim 42, wherein the surface includes a glass surface.

46. A method of fusing desiccant to a surface, comprising:

providing a surface; and

impact spraying desiccant onto the surface, wherein the desiccant becomes fused to the surface.

47. The method of claim 46, wherein the surface is glass.