Micro-electromechanical system

• US 20020109903A1
• Filed: 12/21/2001
• Published: 08/15/2002
• Est. Priority Date: 12/21/2000
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Kaeriyama, Toshiyuki
• Granted Patent: US 6,618,186 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

Abstract

To suppress undesired scattered light and leaking light so as to improve the optical function and reliability. In this DMD, as the address circuit of one cell, SRAM 12 is formed monolithically on the principal surface of silicon substrate 10, and, on said SRAM 12, reflective digital optical switch or optical modulating element 16 is formed monolithically as one cell made of three layers of a metal, such as aluminum, via oxide film 14. Each reflective optical modulating element 16 has bias bus 18 and yoke address electrodes 20, 22 as the first metal layer, torsional hinge 24, hinge supporting portions 26, 28, yoke 30, and mirror address electrodes 32, 34 as the second metal layer, and mirror 36 as the third metal layer. Optical absorptive and nonconductive film 40 is formed to cover a portion or all of the first metal layer and to cover underlying film (insulating film) 14. In addition, said film 40 is formed to bury hole formed on the surface of the third metal layer.

Claims

1. A micro-electromechanical system comprising:

a substrate;

an electrical circuit formed on said substrate;

a mechanism supported by said substrate and operable under the control of said electrical circuit;

an optical absorptive film on at least a portion of said mechanism, said optical absorptive film being a fluorine containing resin with carbon black dispersed in it.

2. The micro-electromechanical system of claim 1, said mechanism comprising:

at least one movable portion spaced apart from said substrate, said optical absorptive film being supported on said substrate around at least a perimeter of said movable portion.

3. The micro-electromechanical system of claim 1, said mechanism comprising:

at least two movable portions spaced apart from said substrate, said movable portions separated by gaps, said optical absorptive film being supported on said substrate in a region proximate said gaps.

4. The micro-electromechanical system of claim 1, said mechanism comprising:

at least one reflective movable portion having a hole in a reflective surface proximate a support member, said optical absorptive film being supported said support member.

5. The micro-electromechanical system of claim 1, said optical absorptive film comprising:

a fluorine containing polymer and a fluorine containing resin cyclic structure in its principal chain.

6. The micro-electromechanical system of claim 1, said optical absorptive film comprising:

carbon black.

7. The micro-electromechanical system of claim 1, said optical absorptive film comprising:

carbon black with an average particle size smaller than 0.1 μ

m.

8. The micro-electromechanical system of claim 1, said optical absorptive film comprising:

oligomer-type fluorine-containing surfactant.

9. The micro-electromechanical system of claim 1, said optical absorptive film comprising:

aprotic fluorine-containing solvent.

10. The micro-electromechanical system of claim 1, said optical absorptive film comprising:

fluorine-containing alcohol.

11. The micro-electromechanical system of claim 1, said optical absorptive film comprising:

a fluorine-containing polymer; and

carbon black;

wherein the proportion of carbon black with respect to the sum of fluorine-containing polymer and carbon black is 1 to 30% by mass.

12. The micro-electromechanical system of claim 1, said optical absorptive film comprising:

an oligomer-type fluorine-containing surfactant; and

carbon black;

wherein the proportion of said carbon black with respect with respect to carbon black is 1 to 20% by mass.

13. The micro-electromechanical system of claim 1, said optical absorptive film comprising:

a fluorine containing alcohol; and

an aprotic fluorine containing solvent;

wherein the proportion of fluorine-containing alcohol with respect to the total mass of aprotic fluorine containing solvent and fluorine-containing alcohol is 10 to 20% by mass.

15. The micro-electromechanical system of claim 14, wherein the proportion of carbon black with respect to the sum of fluorine-containing polymer and carbon black is 1 to 30% by mass.

16. The micro-electromechanical system of claim 14, wherein the proportion of said carbon black with respect with respect to carbon black is 1 to 20% by mass.

17. The micro-electromechanical system of claim 14, wherein the proportion of fluorine-containing alcohol with respect to the total mass of aprotic fluorine containing solvent and fluorine-containing alcohol is 10 to 20% by mass.

18. The micro-electromechanical system of claim 14, said optical absorptive film comprising:

carbon black with an average particle size smaller than 0.1 μ

m.

19. The micro-electromechanical system of claim 14, said mechanism comprising:

at least one movable portion spaced apart from said substrate, said optical absorptive film being supported on said substrate around at least a perimeter of said movable portion.

20. The micro-electromechanical system of claim 14, said mechanism comprising:

at least two movable portions spaced apart from said substrate, said movable portions separated by gaps, said optical absorptive film being supported on said substrate in a region proximate said gaps.

21. The micro-electromechanical system of claim 14, said mechanism comprising:

at least one reflective movable portion having a hole in a reflective surface proximate a support member, said optical absorptive film being supported said support member.

14. A micro-electromechanical system comprising:

a substrate;

an electrical circuit formed on said substrate;

a mechanism supported by said substrate and operable under the control of said electrical circuit;

an optical absorptive film on at least a portion of said mechanism, said optical absorptive film comprising;

a fluorine containing polymer and a fluorine containing resin cyclic structure in its principal chain;

carbon black;

oligomer-type fluorine-containing surfactant;

aprotic fluorine-containing solvent; and

fluorine-containing alcohol.