Packaging for an interferometric modulator

• US 20050254115A1
• Filed: 05/12/2004
• Published: 11/17/2005
• Est. Priority Date: 05/12/2004
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Iridigm Display Corporation (Qualcomm, Inc.)
• Inventors: Chui, Clarence, Cummings, William J., Kothari, Manish, Palmateer, Lauren Fay, Gally, Brian James
• Granted Patent: US 7,164,520 B2
• Time in Patent Office: Days
• US Class Current: 359/276
• 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

A package is made of a transparent substrate having an interferometric modulator and a back plate. A non-hermetic seal joins the back plate to the substrate to form a package, and a desiccant resides inside the package. A method of packaging an interferometric modulator includes providing a transparent substrate and manufacturing an interferometric modulator array on a backside of the substrate. A back plate is provided and a desiccant is applied to the back plate. The back plate is sealed to the backside of the substrate with a back seal in ambient conditions, thereby forming a package

Claims

1. A package, comprising:

a transparent substrate;

an interferometric modulator on the substrate;

a back plate;

a seal joining the back plate to the substrate to form a package; and

a desiccant inside the package.

2. The package of claim 1, the transparent substrate further comprising one selected of the group comprised of:

glass, plastic, and transparent polymers.

3. The package of claim 1, the seal further comprising a non-hermetic seal.

4. The package of claim 1, the seal further comprising a hermetic seal.

5. The package of claim 1, the interferometric modulator further comprising one selected of the group comprised of:

a membrane modulator, and a separable modulator.

6. The package of claim 1, the back plate further comprising one selected from the group comprised of:

glass, metal, foil, polymer, plastic, ceramic and semiconductor materials.

7. The device of claim 1, the seal further comprising one selected from the group comprised of:

epoxy-based adhesives, o-rings, PIBs, poly-urethane, thin film metal welds, liquid spin-on glass, solder, polymers, and plastics.

8. The device of claim 1, the desiccant further comprising one selected from the group comprised of:

zeolites, molecular sieves, desiccants, surface adsorbents, bulk adsorbents, and chemical reactants.

9. A method of packaging an interferometric modulator, comprising:

providing a transparent substrate;

manufacturing an interferometric modulator array on a back side of the substrate;

providing a back plate;

applying a desiccant to the back plate;

sealing the back plate to the backside of the substrate with a back seal in ambient conditions, thereby forming a package.

10. A method of claim 9, the method comprising

sealing in non-ambient conditions as a controlled environment of one of either inert gas or dry air.

11. The method of claim 9, the method comprising:

hardening the back seal;

scribing the substrate between multiple packages;

breaking the substrate into individual devices; and

applying an end seal to the individual devices.

12. The method of claim 9, providing a back plate further comprising providing a back plate having recessed regions.

13. The method of claim 12, providing a back plate with recessed regions further comprising forming ribs on the back plate.

14. The method of claim 13, forming ribs on the back plate further comprising patterning ribs onto the back plate.

15. The method claim 13, forming ribs on the back plate further comprising printing a material onto the back plate.

16. The method of claim 13, forming ribs on the back plate further comprising stenciling a material onto the back plate.

17. The method of claim 12, providing a back plate having recessed regions further comprising eroding the back plate in those regions to form cavities.

18. The method of claim 12, providing a back plate having recessed regions further comprising providing a back plate having molded regions.

19. The method of claim 12, providing a back plate having recessed regions further comprising mounting a frame on a flat back plate, wherein the frame defines cavities between struts of the frame and the transparent substrate.

20. The method of claim 9, providing a back plate further comprising providing a sheet of foil with integral spacer posts such that the spacer posts lie between multiple interferometric modulator arrays on the transparent substrate.

21. The method of claim 9, providing a transparent substrate further comprising providing a transparent substrate with recessed regions in which the interferometric modulators are formed.

22. The method of claim 9, providing a back plate further comprising providing a flexible, polymer sheet.

23. The method of claim 9, providing a transparent substrate further comprising providing a transparent substrate having integrated spacers.

24. The method of claim 9, applying the desiccant further comprising:

aligning the transparent substrate to the back plate;

joining the transparent substrate to the back plate;

sealing the back plate to the transparent substrate.

25. The method of claim 9, applying the desiccant further comprising:

applying the desiccant through a hole; and

sealing the hole

26. The method of claim 9, sealing the back plate to the transparent substrate further comprising sealing the back plate to the transparent substrate with a self-healing seal.

27. The method of claim 9, sealing the back plate to the transparent substrate further comprising sealing a hole in the back plate.

28. The method of claim 9, sealing the back plate to the transparent substrate further comprising forming a seal line wide enough such that the seal is not broken when the substrate is scribed and broken.

29. The method of claim 9, sealing the back plate to the transparent substrate further comprising sealing the back plate to the transparent substrate in an environment having a vacuum.

30. The method of claim 29, the method further comprising maintaining the vacuum pressure in the package.

31. The method of claim 9, sealing the back plate to the transparent substrate further comprising sealing the back plate to the transparent substrate in an environment having a initial vacuum, where environmental pressure increases from vacuum to a higher pressure as sealing occurs such that, as pressure in the package increases due to reduced volume, increased environmental pressure aids in creating a good seal.

32. The method of claim 9, sealing the back plate to the transparent substrate further comprising sealing the back plate to the transparent substrate in an environment having a pressure of higher than vacuum up to and including ambient pressure to form the seal.

33. The method of claim 31, the method further comprising maintaining the higher pressure up to and including ambient pressure in the package.

34. The method of claim 9, sealing the back plate to the transparent substrate further comprising sealing the back plate to the transparent substrate in an environment having a initial pressure higher than vacuum up to an including ambient pressure, where environmental pressure then increases to a higher pressure than the initial pressure as sealing occurs such that, as pressure in the package increases due to reduced volume, increased environmental pressure aids in creating a good seal.

35. The method of claim 9, sealing the back plate to the transparent substrate further comprising sealing the back plate to the transparent substrate in an environment having a pressure higher than ambient pressure to form the seal

36. The method of claim 35, the method further comprising maintaining the higher pressure in the package.

37. The method of claim 9, sealing the back plate to the transparent substrate further comprising sealing the back plate to the transparent substrate in an environment having an initial environmental pressure higher than ambient pressure, wherein the environmental pressure then increases to a higher pressure than the initial pressure as sealing occurs such that, as pressure in the package increases due to reduced volume, increased environmental pressure aids in creating a good seal.

38. The method of claim 31, the increased pressure inside the package during sealing creates a convex backplane shape by partial adhesive curing during a period of time in which the package is at the higher pressure.

39. The method of claim 34, the increased pressure inside the cavity during sealing creates a convex backplane shape by partial adhesive curing during a period of time in which the cavity is at the higher pressure.

40. The method of claim 37, the increased pressure inside the package during sealing creates a convex backplane shape by partial adhesive curing during a period of time in which the package is at the higher pressure.