Yokeless hidden hinge micromirror device with double binge layer

• US 7,088,486 B2
• Filed: 01/16/2003
• Issued: 08/08/2006
• Est. Priority Date: 01/31/2002
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: DiCarlo, Anthony
• Primary Examiner(s): Cherry, Euncha P.
• Application Number:
  US10/345,586
• Publication Number:
  US 20030142382A1
• Time in Patent Office: 1,300 Days
• Field of Search: 359/223, 359/291, 359/224, 353/98, 353/99
• US Class Current: 359/224.1
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means
• CPC Class Codes: Y10S 359/904 Micromirror

Abstract

A micromirror array 110 fabricated on a semiconductor substrate 11. The array 110 is comprised of four operating layers 12, 13, 14, 15. An addressing layer 12 is fabricated on the substrate. A raised electrode layer 13 is spaced above the addressing layer by an air gap. A hinge layer 14 is spaced above the raised electrode layer 13 by another air gap. A mirror layer 15 is spaced over the hinge layer 14 by a third air gap.

Claims

1. An array of micromirror pixel elements, comprising:

a semiconductor substrate layer having circuitry for controlling the operation of the pixel elements;

a mirror layer having a mirror associated with each pixel element;

a hinge layer spaced between the mirror layer and the substrate layer, the hinge layer having a torsion hinge under each mirror and attached to the mirror such that the mirror may tilt above the hinge layer;

a raised electrode layer spaced between the hinge layer and the substrate layer and having at least one raised electrode; and

an address electrode layer spaced between the raised electrode layer and the substrate.

2. The array of claim 1, wherein each mirror is rectangular in shape, wherein the hinge is under the diagonal axis of the mirror such that the mirror tilts around the diagonal axis.

3. The array of claim 1, wherein the raised electrode and the hinge are fabricated from the same material.

4. The array of claim 1, wherein the raised electrode is fabricated from a metallic material.

5. The array of claim 1, wherein the hinge layer further has spring tips under each mirror and mechanically connected to one or more of the underlying layers.

6. The array of claim 5, wherein the spring tips extend from at least one spring tip beam that is connected to the address layer with one or more spring tip support vias.

7. The array of claim 6, wherein the binge and the spring tip beams form a continuous pattern of the hinge layer.

8. The may of claim 1, further comprising a substrate having electrical components fabricated on the substrate.

9. The array of claim 1, wherein the raised electrode layer further has structure for supporting the hinges of the hinge layer.

10. The array of claim 1, wherein the raised electrode layer further has structure for supporting the spring tips of the hinge layer.

11. The array of claim 1, wherein the address layer has address electrodes connected to the raised electrodes.

12. The array of claim 1, wherein the raised electrodes are attached to the addressing layer by means of support posts.

13. The array of claim 1, wherein the raised electrodes extend to the outer tips of the mirrors.

14. The array of claim 1, wherein the hinge layer further has a raised electrodes under the mirrors.

15. The array of claim 1, wherein the raised electrode is closer to a hinge axis that the spring tips.