Mirror device with an anti-stiction layer

• US 20090231667A1
• Filed: 05/02/2008
• Published: 09/17/2009
• Est. Priority Date: 05/03/2007
• Status: Active Grant

• Current Assignee: Ignite USA (Ignite)
• Original Assignee: Olympus Corporation, Silicon Quest Kabushiki-Kaisha
• Inventors: Maeda, Yoshihiro, Ichikawa, Hirotoshi, Watanabe, Kazuhiro, Ishii, Fusao
• Granted Patent: US 7,880,952 B2
• Time in Patent Office: Days
• US Class Current: 359/290
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means
• CPC Class Codes: G03B 21/28 Reflectors in projection beam in illumination beam G03B21/2066
• CPC Class Codes: Y10T 29/49002 Electrical device making

Abstract

A micromirror device includes an elastic hinge for supporting a mirror on a substrate, and an address electrode for deflecting the mirror. The device further includes a protective layer and an oriented monolayer laid to cover a stopper also functioning as an address electrode provided below the mirror and between the mirror and the substrate.

Claims

1. A micromirror device, comprising:

an elastic hinge having conductivity for connection on a substrate between a mirror and the substrate;

an address electrode for deflection of the mirror;

a protective layer provided to cover the address electrode; and

an oriented monolayer provided in any of the mirror, the elastic hinge, and the protective layer, wherein

the oriented monolayer comprises a compound of a plurality of oriented monomolecules.

2. The device according to claim 1, wherein:

the oriented monolayer comprises a halogenated alkyl silicide or an alkyl silicide.

3. The device according to claim 1, wherein:

the oriented monolayer comprises a compound of two or more oriented monomolecules of coupled molecules of different number of at least carbon or halogen.

4. The device according to claim 1, wherein:

the oriented monolayer is configured by combining any one or two or more of perfluorodecyltrichlorosilane, dichlorodimethylsilane, vinyl trimethoxy silane, octadecyltrichlorosinan, undecenyltrichlorosilane, decyltrichlorosilane, fluorooctatrichlorosilane, perfluorodecyldimethylchlorosilane, and perfluorooctyldimethylchlorosilane.

5. The device according to claim 1, wherein:

the oriented monolayer is configured by laying a plurality of monolayers.

6. The device according to claim 1, wherein:

the oriented monolayer is configured by laying a plurality of monolayers, the end portion coupled to the substrate of the material of the first layer is halogenated silane, and the other end portion has any of hydrogen, hydroxyl, and carboxyl.

7. The device according to claim 1, wherein:

the oriented monolayer is configured by laying a plurality of monolayers;

the first and second layers are made of different materials; and

the end portion of the material of the second layer coupled to the oriented monolayer film of the first layer is halogenated silane or carboxyl, and the other end portion is —

CF₃.

8. The device according to claim 1, wherein:

the oriented monolayer is configured by laying a plurality of monolayers; and

the end portion of the oriented monolayer of the first layer is alkyl silicide, and the other end portion is hydrogen or halogenated carbon as hydroxyl.

9. The device according to claim 1, wherein:

the oriented monolayer is configured by laying a plurality of monolayers;

the first and second layers are configured by different materials; and

the second layer is made of the material of CF₃(CF₂)_x(CH₂)_ySi(CH₃)_nCl_3-n (0≦

n≦

2).

10. The device according to claim 1, wherein:

in a mirror array, one side of the substantially square mirror is about 11 μ

m of less, and a gap from an adjacent mirror is 0.55 μ

m or less.

11. The device according to claim 1, wherein:

a distance between a lower surface of the mirror and the protective layer is 1 μ

m or less.

12. A method for producing a micromirror device, comprising:

arranging a plurality of mirrors above a substrate such that a gap between adjacent mirrors is 0.55 μ

m or less;

forming;

a stopper portion for determining a deflection angle of the mirror;

an address electrode for deflecting the mirror; and

an elastic hinge having a width larger than the gap between the mirrors, arranged as enclosed by the stopper portions, having conductivity, and connecting the mirror with the substrate;

providing a protective layer to cover the address electrode; and

laying an oriented monolayer having a compound of a plurality of oriented monomolecules on any of the mirror, the elastic hinge, and the protective layer through the gap between the mirrors.

13. A projection device comprising:

a projection device provided with a micromirror device comprising;

a mirror capable of deflecting incident light at least in two optical states, that is, an ON light state in which incident light is reflected toward a projected light path and an OFF light state in which the incident light is reflected in the direction other than the projected light path,

a deformable elastic hinge for supporting the mirror arranged on the substrate;

an address electrode for providing Coulomb force for deflecting the mirror arranged on the substrate below the mirror;

a stopper regulating the deflection angle of the mirror; and

a drive circuit for providing a potential difference between the mirrors formed on the substrate and the address electrode, wherein

the stopper comprises two or more different types of oriented monolayers including molecules having a number of halogenated carbon of 6 or less.