Method and system for packaging MEMS devices with glass seal

• US 8,735,225 B2
• Filed: 03/31/2009
• Issued: 05/27/2014
• Est. Priority Date: 09/27/2004
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Palmateer, Lauren, Cummings, William J., Gally, Brian, Chui, Clarence, Kothari, Manish
• Primary Examiner(s): Tran, Minh-Loan T
• Assistant Examiner(s): Erdem, Fazli
• Application Number:
  US12/415,986
• Publication Number:
  US 20090189230A1
• Time in Patent Office: 1,883 Days
• Field of Search: 257/415, 438/127
• US Class Current: 438/127
• CPC Class Codes: B81B 7/0038 using materials for controlling the level of pressure, contaminants or moisture inside of the package, e.g. getters
• 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

Methods and systems for packaging MEMS devices such as interferometric modulator arrays are disclosed. One embodiment of a MEMS device package structure includes a seal with a chemically reactant getter. Another embodiment of a MEMS device package comprises a primary seal with a getter, and a secondary seal proximate an outer periphery of the primary seal. Yet another embodiment of a MEMS device package comprises a getter positioned inside the MEMS device package and proximate an inner periphery of the package seal.

Claims

1. A method of sealing an electromechanical systems device package, comprising:

positioning a substrate and a backplane in proximity to each other, the substrate supporting an electromechanical systems device formed thereon;

laser welding the backplane to the substrate to form a seal proximate to a perimeter of the electromechanical systems device, the seal formed only of at least one of substrate material and backplane material fused via the laser welding, the substrate and the backplane encapsulating the electromechanical systems device in a package, wherein the seal is formed of at least one of spin-on glass and glass frit; and

forming a secondary seal on the exterior of the package.

11. The method of claim 1, wherein the electromechanical systems device comprises a microelectromechanical systems device.

12. The method of claim 11, wherein the microelectromechanical systems device comprises an interferometric modulator.

13. The method of claim 11, wherein the microelectromechanical systems device comprises an array of interferometric modulators.

14. The method of claim 1, wherein the seal comprises a substantially hermetic seal.

15. The method of claim 1 further comprising providing a desiccant inside the package.

16. The method of claim 1 further comprising providing a getter inside the package.

17. The method of claim 1, wherein a cavity exists between the electromechanical systems device and the backplane.

18. The method of claim 1, wherein the method is performed in ambient pressure.

19. The method of claim 1, wherein the method is performed in a partial vacuum.

20. The method of claim 1, wherein the method is performed in pressure higher than ambient pressure.

21. The method of claim 1, wherein the method is performed in ambient temperature.

22. The method of claim 1, wherein the method is performed in a completely dry environment.

23. The method of claim 1, wherein the method is performed in an inert gas at ambient temperature and pressure.

24. The method of claim 1 further comprising electrically connecting the electromechanical systems device to a processor.

2. A system for sealing an electromechanical systems device package, comprising:

a substrate;

an electromechanical systems device formed on the substrate;

a backplane;

a seal positioned proximate to a perimeter of the electromechanical systems device, the seal formed only of at least one of fused substrate material and backplane material, the electromechanical systems device encapsulated between the substrate and the backplane in a package, and the seal is formed of at least one of spin-on glass and glass frit; and

a secondary seal disposed on an exterior of the package.

3. The system of claim 2, wherein the electromechanical systems device is a microelectromechanical systems device.

4. The system of claim 3, wherein the microelectromechanical systems device is an interferometric modulator.

5. The system of claim 2, wherein the seal is a substantially hermetic seal.

6. The system of claim 2, wherein the seal is one of a closed seal or an open seal.

7. The system of claim 2 further comprising a desiccant in the package.

8. The system of claim 2 further comprising a getter in the package.

9. The system of claim 2, wherein a cavity exists between the electromechanical systems device and the backplane.

10. The system of claim 2 further comprising a processor electrically connected to the electromechanical systems device.

25. A system for sealing an electromechanical systems device package, comprising:

a substrate including an electromechanical systems device formed thereon;

a backplane including at least one of liquid spin-on glass and glass frit;

a seal positioned proximate to a perimeter of the electromechanical systems device, the seal formed only of at least one of fused substrate material and backplane material, and wherein the electromechanical systems device encapsulated between the substrate and the backplane in a package; and

a secondary seal disposed on an exterior surface of the package.

26. The system of claim 25, wherein the electromechanical systems device is an interferometric modulator.

27. The system of claim 25, wherein the seal is a substantially hermetic seal.

28. The system of claim 25 further comprising a desiccant in the package.