Mirror device with flat and smooth mirror surface without protrusion or dip

• US 8,331,010 B2
• Filed: 07/14/2009
• Issued: 12/11/2012
• Est. Priority Date: 05/23/2005
• Status: Active Grant

• Current Assignee: Ignite USA (Ignite)
• Original Assignee: Silicon Quest Kabushiki-Kaisha
• Inventors: Ishii, Fusao
• Primary Examiner(s): Martinez, Joseph P
• Assistant Examiner(s): THOMAS, BRANDI N
• Application Number:
  US12/460,206
• Publication Number:
  US 20100033800A1
• Time in Patent Office: 1,246 Days
• Field of Search: 359290-292, 359/298
• US Class Current: 359/290
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means
• CPC Class Codes: G09G 3/2011 by amplitude modulation
• CPC Class Codes: G09G 3/346 based on modulation of the reflection angle, e.g. micromirrors micromirrors devices per se G02B26/0833

Abstract

This invention discloses a mirror device comprises a mirror array. The mirror array includes multiple mirror elements. Each element comprises a mirror supported on a hinge. The hinge is attached directly to the mirror and is substantially perpendicular to the mirror. The hinge penetrates a bottom surface of the mirror with a hinge-top buried in a layer of the mirror beneath a top surface of the mirror.

Claims

1. A mirror device comprising

a mirror array comprises multiple mirror elements;

each element comprises a mirror supported on a hinge;

said hinge is attached directly to said mirror and is substantially perpendicular to said mirror;

said hinge penetrates a bottom surface of said mirror with a hinge-top buried in a layer of said mirror beneath a top surface of said mirror; and

said hinge further comprises a hinge foot extending laterally from said hinge along substantially a horizontal direction wherein said hinge-foot is disposed on a first hinge-base migration stop layer on top of a hinge base for preventing a migration of a hinge base material to said hinge.

2. The mirror device of claim 1 wherein:

said hinge penetrates said bottom surface of said mirror with said hinge-top buried in a sacrificial layer, constituting a layer of said mirror below said top surface of said mirror.

3. The mirror device of claim 1 wherein:

said hinge is electrically connected to a ground potential.

4. The mirror device of claim 1 wherein:

said top surface of said mirror is substantially a flat and smooth mirror surface.

5. The mirror device of claim 1 wherein:

said hinge penetrates said bottom surface of said mirror with said hinge-top buried in a layer with a penetration depth of approximately equal to or greater than 100 Angstroms in said mirror beneath a top surface of said mirror.

6. The mirror device of claim 1 wherein:

said hinge further comprises a migration stop layer disposed on top of said hinge top buried in said layer of said mirror to insulate said hinge from said mirror for preventing a migration of a mirror material to said hinge.

7. The mirror device of claim 1 wherein:

said mirror comprises a aluminum mirror and said hinge comprises a semiconductor hinge.

8. The mirror device of claim 1 wherein:

a top portion of said hinge further penetrates said bottom surface of said mirror with said, hinge-top buried in a layer with a penetration depth of exceeding five percent (5%) and below two-third (⅔

) of a thickness of said mirror in said mirror beneath a top surface of said mirror.

9. The mirror device of claim 1 wherein:

said mirror is composed of a metallic material and said hinge is composed of a semiconductor material wherein said hinge and said mirror constitutes a one-piece structure.

10. The mirror device of claim 1 wherein:

said hinge has a hinge top attached directly to bottom surface of said mirror without penetrating a bottom surface of said mirror and said hinge top having no laterally extending horizontal structure.

11. The mirror device of claim 1 wherein:

said hinge base is composed of a conductive material disposed on a hinge via-connector disposed in a via-hole opened through an inter-layer dielectric (ILD) layer deposited on top of a semiconductor substrate.

12. The mirror device of claim 11 further comprising:

a second hinge base migration stop layer disposed between said ILD layer and said hinge base for preventing a migration of said hinge base material to said ILD layer.

13. The mirror device of claim 1 further comprising:

a first and second electrodes disposed on said ILD layer supported on a semiconductor substrate wherein said hinge base has a height extending from said ILD layer higher than said first and said second electrodes to function as a stopper to stop the mirror at a first and second maximum deflection angles respectfully.

14. The mirror device of claim 1 further comprising:

a first and second electrodes disposed on said ILD layer supported on a semiconductor substrate wherein said hinge base further comprises a first horn and a second horn extended from a top surface of said hinge base on two opposite sides pf said hinge wherein said first horn and second horn have a height extending from said top surface of hinge base higher than said first and said second electrodes to function as a stopper to stop the mirror at a first and second maximum deflection angles respectfully.

15. A mirror device comprising:

a mirror array comprises multiple mirror elements;

each element comprises a mirror supported on a hinge;

said hinge is attached directly to said mirror and is substantially perpendicular to said mirror; and

said hinge penetrates said bottom surface of said mirror with said hinge-top buried in a layer with a penetration depth of exceeding five percent (5%) and below two-third (⅔

) of a thickness of said mirror in said mirror beneath a top surface of said mirror.