Mirror device with an anti-stiction layer

• US 7,944,600 B2
• Filed: 05/02/2008
• Issued: 05/17/2011
• 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
• Primary Examiner(s): Mack; Ricky L
• Assistant Examiner(s): Thomas; Brandi N
• Application Number:
  US12/151,218
• Publication Number:
  US 20090231668A1
• Time in Patent Office: 1,110 Days
• Field of Search: 359290-292, 359/294, 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: 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 disposed on the substrate for applying electric signals for deflecting the mirror to deflect between two opposite maximum deflection angles;

a protective layer covers and electrically insulates the address electrode for said address electrode to contact and stop the mirror in deflecting to one of said maximum deflection angles; and

an oriented monolayer covers over at least a portion of said protective layer on said address electrode for contacting said mirror and preventing said mirror from sticking to said address electrode.

2. The device according to claim 1, wherein:

the oriented monolayer is composed of a halogenated alkyl silicide compound or an alkyl silicide compound.

3. The device according to claim 1, wherein:

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

4. The device according to claim 1, wherein:

the oriented monolayer is composed of a compound having a carbon chain with a saturated or unsaturated carbon bond wherein all or a part of hydrogen (H) coupled to the carbon chain is replaced with a halogen.

5. The device according to claim 1, wherein:

the oriented monolayer is composed of a compound comprising less than six molecules of fluorinated carbon.

6. The device according to claim 1, wherein:

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

n</sub> (0≦

n≦

2) where X and Y are positive integers.

7. The device according to claim 1, wherein:

the oriented monolayer covers over at least two portions of said protective layer on said address electrode for contacting said mirror and preventing said mirror from sticking to said address electrode.

8. The device according to claim 1, wherein:

the elastic hinge is composed of a silicon material; and

doped or spread with at least one of the materials consisted of As, P, Ge, Ti, and Ni.

9. The device according to claim 1, wherein:

the protective layer is composed of one of the materials consisted of SiC, amorphous silicon, or polysilicon.

10. The device according to claim 1, wherein:

the protective layer is composed of one of the materials consisted of SiC, amorphous silicon, or polysilicon, and further includes coupled-Si—

O—

of oxygen and silicon.

11. A method for manufacturing a micromirror device, comprising:

forming an elastic hinge for supporting a mirror on a substrate;

forming an address electrode on the substrate for applying electric signals for deflecting the mirror to deflect between two opposite maximum deflection angles;

covering the address electrode with a protective layer to;

electrically insulate the address electrode for stopping the mirror in deflecting to one of said maximum deflection angles and forming an oriented monolayer in a normal temperature for covering at least a portion of the protective layer on said address electrode for contacting said mirror and preventing said mirror from sticking to said address electrode.

12. The method according to claim 11, wherein:

said step of forming the oriented monolayer further comprises a step of forming the oriented monolayer in a normal temperature and a reduced pressure.

13. The method according to claim 11, wherein:

said step of forming the oriented monolayer further comprises a step of forming the oriented monolayer in a heated environment.

14. A method for manufacturing a micromirror device, comprising:

forming an address electrode on a substrate to contact and stop a mirror when deflecting to a maximum deflection angle;

covering the address electrode with a protective layer for electrically insulating said address electrode; and

forming an oriented monolayer in a normal temperature for cove ring at least a portion of the protective layer on said address electrode for contacting said mirror and preventing said mirror from sticking to said address electrode.

15. The method according to claim 14, wherein:

said step of forming said protective layer comprising a step of forming a silicon layer followed by forming an oxide layer on a surface of the silicon layer.

16. The method according to claim 14, wherein:

the step of forming the oriented monolayer further comprises a step of forming the oriented monolayer in a reduced pressure.

17. The method according to claim 14, wherein:

the step of forming the oriented monolayer further comprises a step of forming the oriented monolayer as a compound comprising less than six molecules of fluorinated carbon.

18. A micromechanical device, comprising:

an electrically insulated address electrode having a stopper portion of surfaces for contacting and stopping a deflectable micromirror when deflecting to a maximum deflection angle wherein said stopper portion is covered by an oriented monolayer composed of a material of CF₃(CF₂)_x(CH₂)_ySi(CH₃)_nCl<sub>3−

n</sub> (0≦

n≦

2) where X and Y are positive integers.

19. The device according to claim 18, wherein:

the electrically insulated address electrode is electrically connected to a mirror control device for receiving mirror control signals from said mirror control device.

20. The device according to claim 18, further comprising:

another electrically insulated address electrode constituting a first and second electrically insulated address electrodes for contacting and stopping the deflectable micromirror at two opposite maximum deflection angles.