METHOD AND DEVICE FOR PROVIDING ELECTRONIC CIRCUITRY ON A BACKPLATE

• US 20120099179A1
• Filed: 01/03/2012
• Published: 04/26/2012
• Est. Priority Date: 09/27/2004
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Tyger, Karen
• Granted Patent: US 8,218,919 B2
• Time in Patent Office: Days
• US Class Current: 359/292
• 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
• CPC Class Codes: G09G 2300/04 Structural and physical details of display devices
• CPC Class Codes: G09G 3/3466 based on interferometric effect
• CPC Class Codes: Y10T 29/49155 Manufacturing circuit on or in base

Abstract

A MEMS-based display device is described, wherein an array of interferometric modulators are configured to reflect light through a transparent substrate. The transparent substrate is sealed to a backplate and the backplate may contain electronic circuitry fabricated on the backplane. The electronic circuitry is placed in electrical communication with the array of interferometric modulators and is configured to control the state of the array of interferometric modulators.

Claims

1. A device, comprising:

a substrate;

an array of electromechanical devices disposed on a first surface of the substrate;

a backplate sealed to the first surface of the substrate to form a cavity encapsulating the array of electromechanical devices, wherein the backplate is spaced apart from the array of electromechanical devices;

electronic circuitry fabricated on the backplate; and

a plurality of electrical connections providing electronic communication between the electronic circuitry on the backplate and the array of electromechanical devices.

2. The device of claim 1, wherein the array of electromechanical devices includes an array of reflective display elements.

3. The device of claim 2, wherein the substrate includes a light-transmissive material.

4. The device of claim 1, wherein the electronic circuitry is fabricated on a surface of the backplate facing the array of electromechanical devices.

5. The device of claim 1, wherein the electronic circuitry is configured to control the state of the array of electromechanical devices.

6. The device of claim 1, wherein the electrical connections include a first conducting material in electronic communication with said electronic circuitry and a second conducting material in electronic communication with said array of electromechanical devices.

7. The device of claim 4, additionally including an anisotropic conducting film disposed between the first conducting material and the second conducting material.

8. The device of claim 4, wherein said first conducting material includes a bump of conducting material.

9. The device of claim 8, wherein said second conducting material includes a bump of conducting material.

10. The device of claim 4, wherein the second conducting material includes a conductive support post.

11. The device of claim 1, wherein the electronic circuitry fabricated on the backplate includes a layer of silicon fabricated on the first surface of the backplate.

12. The device of claim 11, wherein no adhesive is provided between the layer of silicon and the first surface of the backplate.

13. A method of fabricating a display, comprising:

providing a substrate including an array of electromechanical devices;

providing a backplate;

fabricating electronic circuitry on the backplate;

sealing the substrate to the backplate to form a cavity encapsulating the array of electromechanical devices; and

forming a plurality of electrical connections placing the electronic circuitry on the backplate in electrical communication with the array of electromechanical devices.

14. The method of claim 13, wherein forming a plurality of electrical connections includes:

depositing a first conducting material on the substrate, wherein the first conducting material is in electrical communication with the array of interferometric modulators; and

depositing a second conducting material on the backplate, wherein the second conducting material is in electrical communication with the electronic circuitry, and wherein the first and second conducting materials are deposited prior to sealing the substrate to the backplate.

15. The method of claim 14, wherein said first and second conducting materials include bumps of conducting material, the method additionally including:

positioning said substrate and said backplate such that said bumps of conducting material are brought into contact with one another; and

compressing said transparent substrate and said backplate together.

16. The method of claim 15, additionally including:

depositing a layer of anisotropic conducting film such that it is in contact with one of the first or second conducting material;

positioning said substrate and said backplate such that said both said first and second conducting materials are in electrical contact with the layer of anisotropic conducting film; and

thermally compressing said transparent substrate and said backplate together.

17. The method of claim 13, wherein forming electronic circuitry on the first surface of the backplate includes:

depositing a base layer of silicon on said first surface of said backplate; and

depositing a plurality of metal layers on said base layer of silicon.

18. The method of claim 13, wherein forming electronic circuitry on the first surface of the backplate includes:

forming transistors on the first surface of the backplate; and

forming metallic interconnections between the transistors.

19. A device, comprising:

a substrate;

an array of electromechanical devices disposed on a first surface of the substrate;

a backplate sealed to the first surface of the substrate to form a cavity encapsulating the array of electromechanical devices, wherein the backplate is spaced apart from the array of electromechanical devices;

electronic circuitry fabricated on the backplate; and

means for providing electronic communication between the electronic circuitry fabricated on the backplate and the array of interferometric modulators.

20. The device of claim 19, wherein the providing means include a plurality of electrical connections providing electronic communication between the electronic circuitry on the backplate and the array of electromechanical devices.