MEMS device and interconnects for same

• US 7,570,415 B2
• Filed: 08/07/2007
• Issued: 08/04/2009
• Est. Priority Date: 08/07/2007
• Status: Expired due to Fees

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Sasagawa, Teruo
• Primary Examiner(s): Ben; Loha
• Application Number:
  US11/835,308
• Publication Number:
  US 20090040590A1
• Time in Patent Office: 728 Days
• Field of Search: 359/290, 359/291, 359/295, 359/223, 359/224, 359/237, 359/238, 359/245, 359/585, 427/123, 427/125, 427/162, 427/250, 438/29, 438/48, 438/52, 438/202, 385/8, 385/14, 385/147, 216/13, 216/17, 216/24, 219/543, 345/108
• US Class Current: 359/290
• CPC Class Codes: B81B 2201/047 Optical MEMS not provided for in B81B2201/042 - B81B2201/045
• CPC Class Codes: B81B 7/0006 Interconnects

Abstract

A microelectromechanical systems device having an electrical interconnect between circuitry outside the device and at least one of an electrode and a movable layer within the device. A layer of the electrical interconnect is formed directly under, over, or between a partially reflective layer and a transparent layer of the device. The layer of the electrical interconnect preferably comprises nickel.

Claims

1. A peripheral routing region of a microelectromechanical systems device, comprising:

an electrical interconnect comprising a conductive layer comprising a material selected from the group consisting of nickel, copper, chromium, and silver;

a partially reflective layer; and

a transparent conductor, wherein at least a portion of the conductive layer is directly under, directly over, or between the partially reflective layer and the transparent conductor.

2. The peripheral routing region of claim 1, wherein the transparent conductor is a layer of a lower electrode of the microelectromechanical systems device.

3. The peripheral routing region of claim 2, wherein the electrical interconnect is configured to be electrically connected to at least one of the lower electrode and a movable conductive layer of the microelectromechanical systems device.

4. The peripheral routing region of claim 2, wherein the transparent conductor comprises indium tin oxide under the conductive layer.

5. The peripheral routing region of claim 1, wherein the partially reflective layer comprises chromium.

6. The peripheral routing region of claim 1, wherein the conductive layer is between the transparent conductor and the partially reflective layer.

7. The peripheral routing region of claim 1, wherein the partially reflective layer is over and contacting the conductive layer.

8. The peripheral routing region of claim 1, wherein the conductive layer comprises nickel.

9. The peripheral routing region of claim 8, further comprising a second nickel layer over the conductive layer.

10. The peripheral routing region of claim 9, further comprising a reflective layer under the second layer and contacting the electrical interconnect.

11. The peripheral routing region of claim 10, wherein the reflective layer comprises aluminum.

12. A microelectromechanical systems device, comprising:

an array comprising a lower electrode, a movable upper electrode, and a cavity between the lower electrode and the upper electrode; and

a peripheral region comprising;

a portion of a layer forming the upper electrode in the array; and

a conductive material of an electrical interconnect electrically connected to at least one of the lower electrode and the upper electrode, wherein the conductive material is formed of a layer separate from and below the layer forming the upper electrode in the array, the conductive material comprising a material selected from the group consisting of nickel, chromium, copper, and silver.

13. The microelectromechanical systems device of claim 12, wherein the lower electrode comprises a transparent conductive layer.

14. The microelectromechanical systems device of claim 13, wherein the lower electrode further comprises a partially reflective layer and at least a portion of the conductive material in the peripheral region is directly over the transparent conductive layer and the partially reflective layer.

15. The microelectromechanical systems device of claim 13, wherein the lower electrode further comprises a partially reflective layer and at least a portion of the conductive material in the peripheral region is directly under the transparent conductive layer and the partially reflective layer.

16. The microelectromechanical systems device of claim 13, wherein the lower electrode further comprises a partially reflective layer and at least a portion of the conductive material in the peripheral region is between the transparent conductive layer and the partially reflective layer.

17. The microelectromechanical systems device of claim 13, wherein the upper electrode further comprises a nickel layer over an aluminum layer.

18. The microelectromechanical systems device of claim 12, wherein the upper electrode comprises an aluminum layer.

19. The microelectromechanical systems device of claim 12, wherein the device is an interferometric modulator.

20. The microelectromechanical systems device of claim 12, further comprising:

a display;

a processor that is in electrical communication with said display, said processor being configured to process image data;

a memory device in electrical communication with said processor.

21. The microelectromechanical systems device of claim 20, further comprising:

a driver circuit configured to send at least one signal to said display.

22. The microelectromechanical systems device of claim 21, further comprising:

a controller configured to send at least a portion of said image data to said driver circuit.

23. The microelectromechanical systems device of claim 20, further comprising:

an image source module configured to send said image data to said processor.

24. The microelectromechanical systems device of claim 23, wherein said image source module comprises at least one of a receiver, transceiver, and transmitter.

25. The microelectromechanical systems device of claim 20, further comprising:

an input device configured to receive input data and to communicate said input data to said processor.

26. A method of making a microelectromechanical systems device, comprising:

depositing a first electrode layer over a transparent substrate;

patterning the first electrode layer to form lower electrodes in an array region;

depositing a conductive layer over the transparent substrate, wherein the conductive layer comprises a material selected from the group consisting of nickel, copper, chromium, and silver;

patterning the conductive layer to form a pattern for an electrical interconnect in a peripheral region;

depositing a sacrificial layer over the lower electrodes in the array region;

after patterning the conductive layer, depositing a second electrode layer over the sacrificial layer to form upper electrodes in the array region.

27. The method of claim 26, wherein the first electrode layer is patterned before patterning the conductive layer.

28. The method of claim 26, wherein the conductive layer is patterned before patterning the first electrode layer.

29. The method of claim 26, further comprising a nickel layer over the upper electrodes.

30. The method of claim 26 layer, wherein the electrical interconnect contacts the upper electrodes to form a contact pad in the peripheral region.

31. The method of claim 30, wherein the upper electrodes comprise aluminum and the conductive layer comprises nickel.

32. The method of claim 30, further comprising mounting a driver connected to the contact pad.

33. The method of claim 26, further comprising depositing a dielectric layer over the conductive layer and the lower electrodes after patterning the conductive layer.

34. The method of claim 26, wherein the lower electrodes are formed over the conductive layer.

35. The method of claim 26, wherein the conductive layer is formed over the lower electrodes.

36. The method of claim 26, further comprising depositing a dielectric layer over the conductive layer, wherein the conductive layer is formed over the lower electrodes.

37. The method of claim 26, wherein the device is an interferometric modulator.

38. The method of claim 26, further comprising removing the sacrificial layer after patterning the upper electrodes.