Method and system for sealing a substrate

• US 7,259,449 B2
• Filed: 03/16/2005
• Issued: 08/21/2007
• Est. Priority Date: 09/27/2004
• Status: Expired due to Fees

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: IDC, LLC
• Inventors: Floyd, Philip D.
• Primary Examiner(s): Nhu; David
• Application Number:
  US11/089,769
• Publication Number:
  US 20060079098A1
• Time in Patent Office: 888 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, wherein 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 comprises 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:

a substrate;

a MEMS device on the substrate;

a metal seal, wherein the metal seal is positioned on the substrate proximate a perimeter of the MEMS device, thereby forming an hermetic seal proximate a perimeter of the MEMS device; and

means for sealing said MEMS device in contact with the metal seal, thereby encapsulating the MEMS device within the substrate, the metal seal, and the means for sealing.

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

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

4. The electronic device of claim 1, wherein said sealing means comprises a back-plate.

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

6. The electronic device of claim 1, further comprising one or more adhesion metal layers disposed over the metal seal, wherein the one or more adhesion metal layers are configured for attachment to a backplane.

7. The electronic device of claim 6, wherein the one or more adhesion layers comprises solder.

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

12. A microelectromechanical system (MEMS) device sealed from ambient conditions, comprising:

a MEMS device formed on a substrate;

a substantially metal seal formed on the substrate proximate a perimeter of the MEMS device, wherein the metal seal comprises a metal seed layer or an adhesion layer; and

a backplane in contact with the substantially metal seal, thereby encapsulating the MEMS device within the substrate, the substantially metal seal, and the backplane.

13. The device of claim 12, further comprising one or more adhesion metal layers deposited over the substantially metal seal, wherein the one or more adhesion metal layers are configured for attachment to the backplane.

14. The device of claim 13, wherein the one or more adhesion layers comprises a solder.

15. The device of claim 12, wherein the substantially metal seal comprises a metal seed layer.

23. The device of claim 12, wherein the substantially metal seal is metal.

16. An electronic device, comprising:

a MEMS device formed on a substrate;

a seal comprising metal, wherein said seal is formed on the substrate proximate a perimeter of the MEMS device, thereby forming an hermetic seal proximate a perimeter of the MEMS device; and

a back-plate in contact with the seal, thereby encapsulating the MEMS device within the substrate, the seal, and the back-plate.

17. The electronic device of claim 16, wherein the seal comprises a solder layer.

18. The electronic device of claim 16, wherein the seal comprises at least one of a metal seed layer and an adhesion layer.

19. The electronic device of claim 16, wherein the seal further comprises an adhesion layer.

20. The electronic device of claim 16, wherein the substrate comprises a transparent substrate.

21. The electronic device of claim 16, wherein the seal comprises a metal seed layer and an adhesion layer.

22. The electronic device of claim 16, wherein the MEMS device is an interferometric modulator.