Mirror device with an anti-stiction layer

• US 20090231668A1
• Filed: 05/02/2008
• Published: 09/17/2009
• Est. Priority Date: 05/03/2007
• Status: Active Grant

• Current Assignee: Ignite USA (Ignite), Olympus Corporation
• Original Assignee: Olympus Corporation, Silicon Quest Kabushiki-Kaisha
• Inventors: Maeda, Yoshihiro, Ichikawa, Hirotoshi, Watanabe, Kazuhiro, Ishii, Fusao
• Granted Patent: US 7,944,600 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 for supporting a mirror on a substrate;

an address electrode for deflecting the mirror;

a protective layer provided to cover the address electrode; and

a stopper portion, provided on a surface of the protective layer, for determining a deflection angle of the mirror, wherein

an oriented monolayer is laid at least on the stopper portion.

2. The device according to claim 1, wherein:

the oriented monolayer is made of halogenated alkyl silicide compound or alkyl silicide compound.

3. The device according to claim 1, wherein:

all or a part of hydrogen-H coupled to a carbon chain portion of a molecule having a carbon chain for forming the oriented monolayer is replaced with halogen.

4. The device according to claim 1, wherein:

a carbon chain portion of a molecule having a carbon chain for forming the oriented monolayer forms saturated or unsaturated carbon bond, and all or a part of hydrogen-H coupled to a carbon chain portion is replaced with halogen.

5. The device according to claim 1, wherein:

a number of fluorinated carbon of a molecule configuring the oriented monolayer is 6 or less.

6. The device according to claim 1, wherein:

the oriented monolayer is made of a material of CF₃(CF₂)_x(CH₂)_ySi (CH₃)_nCl<sub>3−

n</sub> (0≦

n≦

2).

7. The device according to claim 1, wherein:

the mirror point-contacts a point of the stopper portion, or substantially point-contacts at least two points of the stopper portion.

8. The device according to claim 1, wherein:

the elastic hinge includes a silicon material; and

one material of any of As, P, Ge, Ti, and Ni is doped or spread.

9. The device according to claim 1, wherein:

the protective layer is SiC, amorphous silicon, or polysilicon.

10. The device according to claim 1, wherein:

the protective layer is SiC, amorphous silicon, or polysilicon, and further includes coupled-Si—

O—

of oxygen and silicon.

11. A micromirror device producing method, comprising the process of forming:

an elastic hinge for supporting a mirror on a substrate;

an address electrode for deflecting the mirror;

a protective layer provided to cover the address electrode; and

a stopper portion, provided on a surface of the protective layer, for determining a deflection angle of the mirror, wherein

an oriented monolayer is formed at least on the stopper portion in the elastic hinge, the address electrode, the protective layer, and the stopper portion; and

when the oriented monolayer is formed, the oriented monolayer is laid in a normal temperature.

12. The method according to claim 11, wherein:

the oriented monolayer is laid in a normal temperature and a reduced pressure.

13. The method according to claim 11, wherein:

the oriented monolayer is laid in a heating environment.

14. A micromirror device producing method, comprising the process of:

forming a stopper portion for determining a deflection angle of a mirror on a substrate;

forming a protective layer for covering at least the stopper portion; and

forming an oriented monolayer on the protective layer in a normal temperature.

15. The method according to claim 14, wherein:

the stopper portion is covered with a protective layer including silicon; and

an oxide layer is formed on a surface of the protective layer.

16. The method according to claim 14, wherein:

the oriented monolayer is laid in a reduced pressure.

17. The method according to claim 14, wherein:

the number of fluorinated carbon of a molecule configuring the oriented monolayer is 6 or less.

18. A micromechanical device, wherein:

a stopper portion contacting a movable member has an oriented monolayer of a material of CF₃(CF₂)_x(CH₂)_ySi(CH₃)_nCl<sub>3−

n</sub> (0≦

n≦

2).

19. The device according to claim 18, wherein:

the stopper portion contacting the movable member is a portion capable of making point contact.

20. The device according to claim 18, wherein:

the movable member contacts the stopper portion when Coulomb force is applied to the stopper portion.