Method and system for sealing a substrate

• US 7,629,678 B2
• Filed: 08/21/2007
• Issued: 12/08/2009
• Est. Priority Date: 09/27/2004
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Floyd, Philip D.
• Primary Examiner(s): Nhu; David
• Application Number:
  US11/842,916
• Publication Number:
  US 20080038876A1
• Time in Patent Office: 840 Days
• Field of Search: 257/678, 257/736, 257/737, 257/738, 257/712, 257/772, 257/779, 257/780, 257/781
• US Class Current: 257/678
• CPC Class Codes: B81C 1/00269 Bonding of solid lids or wafers to the substrate
• CPC Class Codes: B81C 2203/019 characterised by the material or arrangement of seals between parts
• 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 method of sealing a microelectromechanical system (MEMS) device from ambient conditions is described, where the MEMS device is formed on a substrate and a substantially hermetic seal is formed as part of the MEMS device manufacturing process. The method includes forming a metal seal on the substrate proximate a perimeter of the MEMS device using a method such as photolithography. The metal seal is formed on the substrate while the MEMS device retains a sacrificial layer between conductive members of MEMS elements, and the sacrificial layer is removed after formation of the seal and prior to attachment of a backplane.

Claims

1. An electronic device, comprising:

means for supporting a micro-electromechanical systems (MEMS) device;

a MEMS device disposed on the means for supporting;

an insulation layer on the means for supporting;

a substantially metal seal on the insulation layer, thereby forming a substantially hermetic seal;

means for sealing the MEMS device in contact with the substantially metal seal, thereby encapsulating the MEMS device within the means for supporting, the substantially metal seal and the means for sealing; and

conductive leads running through the insulation layer and electrically connecting the MEMS device to an electrical source outside of the electronic device.

2. The electronic device of claim 1, wherein the supporting means comprises a transparent substrate.

3. The electronic device of claim 1, wherein the sealing means comprises a backplane.

4. The electronic device of claim 1, wherein the substantially metal seal comprises a solder layer.

5. The electronic device of claim 1 further comprising an adhesion metal layer disposed over the substantially metal seal, wherein the adhesion metal layer is configured for attachment to a backplane.

6. The electronic device of claim 5, wherein the adhesion layer comprises solder.

7. The electronic device of claim 5, wherein the adhesion layer comprises titanium or chromium.

8. The electronic device of claim 1, wherein the substantially metal seal comprises at least one of a metal seed layer and an adhesion layer.

9. The electronic device of claim 1 further comprising means for attaching the sealing means to the substantially metal seal.

10. The electronic device of claim 9, wherein the attaching means comprises a pre-deposited adhesion layer configured to adhere to the metal seal.

11. The electronic device of claim 1, wherein the MEMS device comprises an interferometric modulator.

12. The electronic device of claim 1, wherein the MEMS device comprises an array of interferometric modulators.

13. The electronic device of claim 1, wherein the means for sealing comprises at least one material selected from the group consisting of glass, metal, foil, polymer, plastic, ceramic and silicon.

14. The electronic device of claim 1, wherein the insulation layer comprises silicon.

15. The electronic device of claim 1, wherein the insulator contacts the means for supporting.

16. The electronic device of claim 1, wherein the insulator is disposed on at least one layer in contact with the means for supporting.

17. The electronic device of claim 16, wherein the at least one layer comprises a conductive material.

18. The electronic device of claim 1 further comprising:

a processor in electrical communication with the MEMS device, the processor being configured to process image data; and

a memory device in electrical communication with the processor.

19. The electronic device of claim 1 further comprising a driver circuit configured to send at least one signal to the MEMS device.

20. The electronic device of claim 19 further comprising a controller configured to send at least a portion of the image data to the driver circuit.

21. The electronic device of claim 18 further comprising an image source module configured to send the image data to the processor.

22. The electronic device of claim 21, wherein the image source module comprises at least one of a receiver, transceiver, and transmitter.

23. The electronic device of claim 18 further comprising an input device configured to receive input data and to communicate the input data to the processor.

24. An electronic device comprising:

a micro-electromechanical systems (MEMS) device on a substrate;

an insulator layer formed on the substrate;

a metal layer on the insulator layer;

a mask with one or more perimeter cavities over the metal layer; and

a metal seal layer deposited in the one or more perimeter cavities, thereby forming a sealant wall.

25. The electronic device of claim 24, wherein the MEMS device comprises an interferometric modulator.

26. The electronic device of claim 24, wherein the insulator layer contacts the substrate.

27. The electronic device of claim 24, wherein the insulator layer is disposed on at least one layer in contact with the substrate.

28. The electronic device of claim 27, wherein the at least one layer comprises a conductive material.

29. The electronic device of claim 24, wherein the substrate comprises a transparent substrate.

30. The electronic device of claim 24, wherein the metal seal layer comprises a solder layer.

31. The electronic device of claim 24, wherein the MEMS device comprises an array of interferometric modulators.

32. The electronic device of claim 24 further comprising:

a processor in electrical communication with the MEMS device, the processor being configured to process image data; and

a memory device in electrical communication with the processor.

33. The electronic device of claim 24 further comprising a driver circuit configured to send at least one signal to the MEMS device.

34. The electronic device of claim 33 further comprising a controller configured to send at least a portion of the image data to the driver circuit.

35. The electronic device of claim 32 further comprising an image source module configured to send the image data to the processor.

36. The electronic device of claim 35, wherein the image source module comprises at least one of a receiver, transceiver, and transmitter.

37. The electronic device of claim 32 further comprising an input device configured to receive input data and to communicate the input data to the processor.