Method and device for modulating light

• US 8,928,967 B2
• Filed: 10/04/2010
• Issued: 01/06/2015
• Est. Priority Date: 04/08/1998
• Status: Expired due to Fees

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Miles, Mark W.
• Primary Examiner(s): TRA, TUYEN Q
• Application Number:
  US12/897,662
• Publication Number:
  US 20110019380A1
• Time in Patent Office: 1,555 Days
• Field of Search: 359/291, 359/292, 359/293, 359/295, 359/298, 359/220, 359/223, 359/224, 359/320, 359/324, 345/204, 345/107, 345/105
• US Class Current: 359/291
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means
• CPC Class Codes: G09G 2300/0809 Several active elements per pixel in active matrix panels
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: G09G 2300/088 using a non-linear two-terminal element
• CPC Class Codes: G09G 3/2014 by modulation of the duration of a single pulse during which the logic level remains constant
• CPC Class Codes: G09G 3/22 using controlled light sources
• CPC Class Codes: G09G 3/3466 based on interferometric effect

Abstract

Improvements in an interferometric modulator that has a cavity defined by two walls.

Claims

1. A device, comprising:

a substrate;

an array of electromechanical devices over the substrate, each of the array of electromechanical devices comprising

a movable first electrode layer,

a first insulator, and

a second electrode; and

a plurality of transistors over the substrate, each of the plurality of transistors comprising

a gate,

a second insulator, and

an electrode,

each of the plurality of transistors electrically coupled to at least one of the movable first electrode layer and a second electrode of an electromechanical device in the array,

wherein, in each of the array of electromechanical devices, a portion of one of the movable first electrode layer, the first insulator, and the second electrode includes a deposited layer of a material, wherein the deposited material comprises a metal; and

wherein, in each of the plurality of transistors, a portion of one of the gate, the second insulator, and the electrode includes the deposited layer of the material.

2. The device of claim 1, wherein the substrate comprises a glass or plastic material.

3. The device of claim 1, wherein the plurality of transistors comprise a plurality of thin film transistors.

4. The device of claim 3, further comprising a voltage source electrically coupled to the plurality of thin film transistors, wherein the voltage source is configured to provide voltage to at least one of the movable first electrode layer and the second electrode via the plurality of thin film transistors.

5. The device of claim 3, wherein each of the plurality of thin film transistors is configured to at least in part control the movement of the movable first electrode layer and/or second electrode with respect to the substrate.

6. The device of claim 3, wherein each of the plurality of thin film transistors is configured to drive the second electrode of an electromechanical device in the array.

7. The device of claim 1, wherein at least one of the electromechanical devices comprises at least one of tantalum, silicon, and aluminum.

8. The device of claim 1, wherein the device comprises an active matrix display.

9. The device of claim 1, wherein a portion of the movable first electrode layer and a portion of the gate each comprise a portion of the deposited material.

10. The device of claim 1, wherein the substrate has a size of at least 14 inches by 16 inches.

11. A method of manufacturing a drive circuit for an array of electromechanical devices, the method comprising:

forming an array of electromechanical devices over a substrate, wherein forming each of the array of electromechanical devices includes

forming a movable first electrode layer,

forming a first insulator, and

forming a second electrode,

wherein one of forming the movable first electrode layer, forming the first insulator, and forming the second electrode layer includes depositing a material in a layer over a substrate, wherein the deposited material comprises one of molybdenum and tantalum; and

forming a plurality of transistors over the substrate, wherein forming each of the plurality of transistors includes

forming a gate,

forming a second insulator, and

forming an electrode,

wherein one of forming the gate, forming the second insulator, and forming the electrode includes depositing the material in the layer over the substrate.

12. The method of claim 11, wherein a portion of the movable first electrode layer and a portion of the gate each comprise a portion of the deposited material.

13. The method of claim 11, wherein the transistor comprises a thin film transistor.

14. The method of claim 13, further comprising connecting the thin film transistor to a voltage source.

15. The method of claim 11, wherein the substrate comprises a plastic material.

16. The method of claim 11, further comprising forming a cavity between the movable first electrode layers and the second electrodes wherein forming the cavity comprises removing a sacrificial layer.

17. The method of claim 16, wherein removing the sacrificial layer comprises etching the sacrificial layer.

18. The method of claim 11, wherein a portion of the second electrode of the electromechanical devices and a portion of the electrodes of the transistors each comprise a portion of the deposited material.

19. The method of claim 11, wherein the substrate has a size of at least 14inches by 16 inches.

20. A method of manufacturing a drive circuit for an array of electromechanical devices, the method comprising:

forming an array of electromechanical devices over a substrate, wherein forming each of the array of electromechanical devices includes

forming a movable first electrode layer,

forming a first insulator, and

forming a second electrode,

wherein one of forming the movable first electrode layer, forming the first insulator, and forming the second electrode layer includes depositing a material in a layer over a substrate; and

forming a plurality of transistors over the substrate, wherein forming each of the plurality of transistors includes

forming a gate,

forming a second insulator, and

forming an electrode,

wherein one of forming the gate, forming the second insulator, and forming the electrode includes depositing the material in the layer over the substrate,

wherein a portion of the second electrode of the electromechanical devices and a portion of the electrodes of the transistors each comprise a portion of the deposited material.

21. The method of claim 20, wherein the transistor comprises a thin film transistor.

22. The method of claim 21, further comprising connecting the thin film transistor to a voltage source.

23. The method of claim 20, wherein the substrate comprises a plastic material.

24. The method of claim 20, further comprising forming a cavity between the movable first electrode layers and the second electrodes wherein forming the cavity comprises removing a sacrificial layer.

25. The method of claim 24, wherein removing the sacrificial layer comprises etching the sacrificial layer.

26. The method of claim 20, wherein the substrate has a size of at least 14inches by 16 inches.