Method and device for packaging a substrate

• US 20060067641A1
• Filed: 01/28/2005
• Published: 03/30/2006
• Est. Priority Date: 09/27/2004
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: IDC, LLC
• Inventors: Palmateer, Lauren, Chui, Clarence, Sampsell, Jeffrey B., Cummings, William J., Kothari, Manish, Gally, Brian, Miles, Mark
• Granted Patent: US 7,424,198 B2
• Time in Patent Office: Days
• US Class Current: 385/147
• 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 1/00333 Aspects relating to packaging of MEMS devices, not covered by groups B81C1/00269 - B81C1/00325
• CPC Class Codes: B81C 2203/0136 Growing or depositing of a covering layer
• CPC Class Codes: B81C 2203/0145 Hermetically sealing an opening in the lid
• 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 26/007 the movable or deformable optical element controlling the colour, i.e. a spectral characteristic, of the light
• CPC Class Codes: G02B 26/0825 the reflecting element being a flexible sheet or membrane, e.g. for varying the focus flexible mirrors for cosmetic use A45D42/24
• 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

A package structure and method of packaging for an interferometric modulator. A thin film material is deposited over an interferometric modulator and transparent substrate to encapsulate the interferometric modulator. A gap or cavity between the interferometric modulator and the thin film provides a space in which mechanical parts of the interferometric modulator may move. The gap is created by removal of a sacrificial layer that is deposited over the interferometric modulator.

Claims

1. A display device, comprising:

a transparent substrate;

an interferometric modulator configured to modulate light transmitted light said transparent substrate; and

a thin film backplane disposed on said modulator and sealing said modulator within a package between said transparent substrate and said thin film backplane.

2. The display device of claim 1, wherein a gap exists between said modulator and said thin film backplane.

3. The display device of claim 2, wherein said gap is formed from removal of a sacrificial layer located between said modulator and said thin film backplane.

4. The display device of claim 1, wherein the thin film backplane comprises a hermetic material.

5. The display device of claim 1, wherein the thin film is nickel.

6. The display device of claim 1, wherein the thin film is aluminum.

7. A method of manufacturing a display device, comprising:

providing a transparent substrate;

forming an interferometric modulator on the transparent substrate; and

depositing a thin film backplane over the interferometric modulator and the transparent substrate to seal said modulator between said transparent substrate and said thin film backplane.

8. The method of claim 7, further comprising:

depositing a sacrificial layer on said interferometric modulator prior to depositing said thin film backplane; and

removing said sacrificial layer after depositing said thin film backplane in order to provide a gap between said interferometric modulator and said thin film backplane.

9. The method of claim 8, further comprising patterning said thin film backplane to create at least one opening in said thin film backplane.

10. The method of claim 8, further comprising patterning said thin film backplane to expose a portion of said sacrificial layer.

11. The method of claim 7, wherein the thin film backplane is formed of aluminum.

12. The method of claim 7, wherein the thin film backplane is formed of nickel.

13. The method of claim 7, wherein the thin film backplane is formed of spin-on glass.

14. The method of claim 7, wherein the thin film backplane is formed of a hermetic material.

15. The method of claim 8, wherein the sacrificial layer is formed of spin-on glass.

16. A microelectromechanical systems display device, comprising:

a transparent substrate;

an interferometric modulator formed on the transparent substrate; and

a thin film backplane sealed to the transparent substrate to encapsulate the interferometric modulator between the transparent substrate and the thin film backplane, wherein a cavity exists between the interferometric modulator and the thin film backplane.

17. The microelectromechanical systems display device of claim 16, wherein the cavity is created by removing a sacrificial layer between the interferometric modulator and the thin film backplane.

18. The microelectromechanical systems display device of claim 16, wherein the interferometric modulator comprises moving parts and the cavity allows the moving parts to move.

19. The microelectromechanical systems display device of claim 16, wherein the thin film backplane comprises a hermetic material.

20. The microelectromechanical systems display device of claim 16, further comprising an overcoat layer deposited over the thin film backplane.

21. The microelectromechanical systems display device of claim 20, wherein the overcoat layer comprises a vapor barrier material.

22. The microelectromechanical systems display device of claim 20, wherein the overcoat layer comprises a polymer.

23. The microelectromechanical systems display device of claim 16, wherein the thin film backplane comprises a metal.

24. The microelectromechanical systems display device of claim 16, wherein the thin film backplane comprises a polymer.

25. A display device, comprising:

a transparent substrate;

an interferometric modulator configured to modulate light transmitted through the transparent substrate, wherein the interferometric modulator is formed on the transparent substrate;

a thin film backplane deposited over the interferometric modulator, wherein the thin film backplane seals the modulator within a package between the transparent substrate and the thin film backplane; and

a cavity between the modulator and the thin film backplane, wherein the cavity is formed by removing a sacrificial material.

26. The display device of claim 25, wherein the thin film backplane is hermetic.

27. The display device of claim 25, wherein the thin film backplane is a metal.

28. The display device of claim 25, wherein the thin film backplane is a polymer.

29. A display device, comprising:

a transmitting means for transmitting light therethrough;

a modulating means configured to modulating light transmitted through the transmitting means, wherein the modulating means comprises an interferometric modulator; and

a sealing means for sealing the modulating means within a package between the transmitting means and the sealing means, wherein the sealing means comprises a thin film.

30. The display device of claim 29, wherein a cavity exists between the modulating means and the sealing means.

31. The display device of claim 30, wherein the cavity is formed by removing a sacrificial layer between the modulating means and the sealing means.

32. The display device of claim 29, wherein the sealing means comprises a hermetic material.

33. The display device of claim 29, wherein the thin film is permeable to xenon diflouride and the sealing means further comprises a hermetic material formed over the thin film.