High aperture-ratio top-reflective AM-iMod displays

• US 7,643,199 B2
• Filed: 06/19/2007
• Issued: 01/05/2010
• Est. Priority Date: 06/19/2007
• Status: Expired due to Fees

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Lan, Je-Hsiung
• Primary Examiner(s): Sugarman; Scott J
• Assistant Examiner(s): PINKNEY, DAWAYNE
• Application Number:
  US11/765,276
• Publication Number:
  US 20080316566A1
• Time in Patent Office: 931 Days
• Field of Search: 359/247, 359/245, 359301-303, 359260-261, 359/298, 359317-318, 359/577, 359290-292, 359223-225, 359262-263, 359/295, 359/198
• US Class Current: 359/247
• 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

High-aperture-ratio devices comprise active-matrix elements and interferometric modulators and methods of making thereof. The active-matrix element may be positioned behind the interferometric modulator with respect to incident light. In some embodiments, components of the active-matrix element may be formed on a first substrate, while components of the interferometric modulator may be formed on a second substrate, and the substrates may then be attached.

Claims

1. An interferometric display device, comprising:

a first substrate;

a first portion of at least one interferometric modulator configured to modulate incident light formed on the first substrate, the first portion comprising a fixed electrode;

a second substrate;

a second portion of the at least one interferometric modulator formed on the second substrate, the second portion comprising a movable electrode;

at least one control element formed on the second substrate and directly coupled to at least one of the fixed electrode and the movable electrode, the at least one control element comprising one or more of a transistor and an electronic switching element, one wherein the at least one interferometric modulator is disposed between the first substrate and the control element such that the at least one control element is located behind the at least one interferometric modulator with respect to the incident light; and

at least one support, formed between the first substrate and the second substrate and connecting the first portion and the second portion, the at least one support defining a spacing between the movable electrode and the first portion.

2. The device of claim 1, wherein the first substrate comprises glass and wherein the second substrate comprises silicon.

3. The device of claim 1, wherein the fixed electrode comprises a partially light-reflecting electrode and the movable electrode defines an interferometric cavity with the fixed electrode, and

wherein the at least one interferometric modulator additionally comprises:

at least one first support between the partially light-reflecting electrode and the movable electrode.

4. The device of claim 1, further comprising at least one additional support between the at least one control element and the at least one interferometric modulator.

5. The device of claim 4, wherein the at least one additional support supports the at least one control element behind the at least one interferometric modulator.

6. The device of claim 5, wherein the at least one additional support comprises a flexible component.

7. The device of claim 1, further comprising an electrical connection between the at least one interferometric modulator and the at least one control element.

8. The device of claim 1, wherein the at least one interferometric modulator is characterized by at least two pixel states and wherein the at least one control element at least partially controls the pixel state of the at least one interferometric modulator.

9. The device of claim 1, further comprising at least one color filter configured to modify a color of light emitted from the at least one interferometric modulator.

10. The device of claim 1, further comprising at least one second interferometric modulator configured to selectively modulate incident light, wherein the at least one interferometric modulator and the at least one second interferometric modulator are formed on a first substrate, the first substrate comprising a substantially transparent layer that serves as an electrode in common to the at least one interferometric modulator and the at least one second interferometric modulator.

11. The device of claim 10, wherein the transparent layer is a contiguous non-patterned layer.

12. The device of claim 1, further comprising:

a display comprising the interferometric display device;

a processor that is configured to communicate with said display, said processor being configured to process image data; and

a memory device that is configured to communicate with said processor.

13. The device of claim 12, further comprising a driver circuit configured to send at least one signal to the display.

14. The device of claim 13, further comprising a controller configured to send at least a portion of the image data to the driver circuit.

15. The device of claim 12, further comprising an image source module configured to send said image data to said processor.

16. The device of claim 15, wherein the image source module comprises at least one of a receiver, transceiver, and transmitter.

17. The device of claim 15, further comprising an input device configured to receive input data and to communicate said input data to said processor.

18. A method of manufacturing a display device, comprising:

forming at least part of an interferometric modulator over a first substrate;

forming at least part of a control element over a second substrate;

positioning the at least part of the control element behind the at least part of the interferometric modulator, such that the first and second substrates are substantially parallel to each other;

forming at least one support between the first and second substrates, wherein the at least one support is formed between a movable electrode of the interferometric modulator and the control element; and

electrically connecting the at least part of the control element to the at least part of the interferometric modulator.

19. The method of claim 18, wherein the control element comprises a transistor.

20. The method of claim 18, wherein electrically connecting comprises:

forming a via in the second substrate; and

forming an electrical connection in the via, the electrical connection coupling the control element and the at least part of the interferometric modulator.

21. The method of claim 18, further comprising operatively attaching the control element to the first substrate.

22. The method of claim 18, further comprising forming an adhesive layer that operatively connects the first substrate to the second substrate.

23. The method of claim 22, wherein the adhesive layer comprises epoxy glue.

24. The method of claim 18, wherein the at least part of the interferometric modulator comprises a light-reflecting electrode, and

further comprising forming a cavity between the partially light-reflecting electrode of the interferometric modulator and a movable electrode of the interferometric modulator.

25. The method of claim 24, wherein forming the cavity between the partially light-reflecting electrode and the movable electrode comprises removing a sacrificial layer between the partially light-reflecting and movable electrodes.

26. The method of claim 24, wherein the forming the cavity between the partially light-reflecting electrode and the movable electrode comprises supporting the movable electrode with supports over the partially light-reflecting electrode.

27. The method of claim 18 wherein the at least one support comprises a flexible component.

28. A microelectromechanical (MEMS) device fabricated by the method of claim 21.

33. The method of claim 18, wherein forming at least part of the interferometric modulator over the first substrate comprises forming a partially light-reflecting electrode over the first substrate.

34. The method of claim 33, wherein forming at least part of the interferometric modulator over the first substrate further comprises forming a movable electrode over the partially light-reflecting electrode to form an interferometric cavity.

35. The method of claim 18, further comprising forming at least another part of the interferometric modulator over the second substrate.

36. The method of claim 35, wherein forming the at least another part of the interferometric modulator over the second substrate comprises forming a movable electrode over the at least part of the control element.

37. The method of claim 18, wherein electrically connecting the at least part of the control element to the at least part of the interferometric modulator comprises electrically connecting the at least part of the control element to a movable membrane of the interferometric modulator.

29. A device comprising:

a first substrate

a first portion of means for interferometrically modulating incident light formed on the first substrate, the first portion comprising a fixed electrode

a second substrate

a second portion of the means for interferometrically modulating incident light formed on the second substrate, the second portion comprising a movable electrode;

means for actively controlling the means for interferometrically modulating incident light, formed on the second substrate and directly coupled to at least one of the fixed electrode and the movable electrode, the controlling means comprising one or more of a transistor and an electronic switching element, wherein the means for interferometrically modulating incident light is disposed between the first substrate and the controlling means such that the controlling means is located behind the means for interferometrically modulating incident light with respect to the incident light; and

means for supporting the movable electrode, formed between the first substrate and second substrate, connecting the first portion and the second portion, the supporting means defining a spacing between the movable electrode and the first portion.

30. The device of claim 29, wherein the means for actively controlling comprises a means for applying a voltage to the fixed electrode or the movable electrode of the means for interferometrically modulating incident light.

31. A method, comprising:

forming at least a part of an active matrix element over a first substrate;

forming at least a part of an interferometric modulator over a second substrate;

positioning the first substrate behind the second substrate;

attaching the first substrate to the second substrate by forming at least one support therebetween, wherein the at least one support is formed between a movable electrode of the interferometric modulator and the active matrix element; and

at least partially controlling the optical response of an interferometric modulator with the active matrix element.

32. The method of claim 31, wherein the active matrix element comprises a transistor.