Method of operating a micromechanical device that contains anti-stiction gas-phase lubricant

• US 7,372,615 B2
• Filed: 03/24/2006
• Issued: 05/13/2008
• Est. Priority Date: 11/23/2005
• Status: Expired due to Fees

• Current Assignee: Miradia Inc. (Walsin Lihwa Corporation)
• Original Assignee: Miradia Inc. (Walsin Lihwa Corporation)
• Inventors: Chen, Dongmin, Xiong, Fulin
• Primary Examiner(s): Surgarman; Scott J.
• Assistant Examiner(s): Thomas; Brandi N
• Application Number:
  US11/389,423
• Publication Number:
  US 20070115531A1
• Time in Patent Office: 781 Days
• Field of Search: 359/290, 359/291, 359/292, 359/295, 359/296, 359/298
• US Class Current: 359/290
• CPC Class Codes: B81B 2201/042 Micromirrors, not used as optical switches
• CPC Class Codes: B81B 3/0005 Anti-stiction coatings
• CPC Class Codes: B81C 1/0096 For avoiding stiction when the device is in use, i.e. after manufacture has been completed
• CPC Class Codes: B81C 2201/112 Depositing an anti-stiction or passivation coating, e.g. on the elastic or moving parts
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: G02B 1/14 Protective coatings, e.g. hard coatings
• CPC Class Codes: G02B 21/32 Micromanipulators structurally combined with microscopes
• CPC Class Codes: G02B 27/0006 with means to keep optical surfaces clean, e.g. by preventing or removing dirt, stains, contamination, condensation G02B1/18 takes precedence; cleaning in general B08B

Abstract

One embodiment of an micromechanical device includes a first contact surface, a moveable component having a second contact surface, where the second contact surface interacts with the first contact surface during device operation, and a gas-phase lubricant disposed between the first contact surface and the second contact surface, where the gas-phase lubricant is adapted to reduce stiction-related forces between the first contact surface and the second contact surface. One advantage of the disclosed device is that a gas-phase lubricant has a high diffusion rate and, therefore, is self-replenishing, meaning that it can quickly move back into a contact region after being physically displaced from the region by the contacting surfaces of the device during operation. Consequently, the gas-phase lubricant is more reliable than conventional solid or liquid lubricants in preventing stiction-related device failures.

Claims

1. A method of operating a micromechanical device assembly comprising:

providing a micromechanical device that comprises;

a first contact surface;

an electrode coupled to a base; and

a mirror coupled to the base and having a conductive region, a reflective mirror surface and a second contact surface, wherein the second contact surface interacts with the first contact surface during device operation; and

a power supply that is in electrical communication with the conductive region and the electrode;

exposing the reflective mirror surface to optical radiation delivered from a light source;

biasing the electrode relative to the conductive region to a potential that causes the mirror to move to a desired position and that causes the first contact surface to interact with the second contact surface; and

disposing a gas-phase lubricant between the first contact surface and the second contact surface at a predetermined pressure, wherein the gas-phase lubricant is not susceptible to substantial fragmentation, breakdown or out-gassing when exposed to the optical radiation and is adapted to reduce stiction between the first contact surface and the second contact surface.

2. The method of claim 1, wherein the gas-phase lubricant is a gas containing a haloalkane.

3. The method of claim 1, wherein the gas-phase lubricant is selected from a group consisting of sulfur hexafluoride, silicon tetrafluonde and perfluorocyclobutane.

4. The method of claim 1, wherein the gas-phase lubricant is a fluorinated compound that has a molecular weight greater than about 100 amu.

14. The method of claim 1, wherein the predetermined pressure is atmospheric pressure or greater.

17. The method of claim 1, wherein the only lubricant disposed between the first contact surface and the second contact surface is the gas-phase lubricant.

20. The method of claim 1, further comprising forming a sealed micromechanical device, assembly, comprising sealing the micromechanical device in a processing region of a sealed enclosure after disposing the gas-phase lubricant between the first contact surface and the second contact surface, wherein the only lubricant disposed in the processing region of the sealed micromechanical device assembly is the gas-phase lubricant.

23. The method of claim 1, wherein contaminants are removed from the micromechanical device assembly prior to disposing the gas-phase lubricant between the first contact surface and the second contact surface.

5. A method of operating a micromechanical device assembly comprising:

providing a micromechanical device that comprises;

a first contact surface; and

a moveable component having a second contact surface, wherein the second contact surface interacts with the first contact surface during device operation;

causing the second contact surface of the moveable component to interact repeatedly with the first contact surface; and

disposing a gas-phase lubricant between the first contact surface and the second contact surface at a predetermined pressure, wherein contaminants are removed from the micromechanical device assembly prior to disposing the gas-phase lubricant, and the gas-phase lubricant is adapted to reduce stiction between the first contact surface and the second contact surface.

6. The method of claim 5, wherein the gas-phase lubricant is a gas containing a haloalkane.

7. The method of claim 5, wherein the gas-phase lubricant is selected from a group consisting of sulfur hexafluoride, silicon tetrafluoride and perfluorocyclobutane.

8. The method of claim 5, wherein the gas-phase lubricant is a fluorinated compound that has a molecular weight greater than about 100 amu.

15. The method of claim 5, wherein the predetermined pressure is atmospheric pressure or greater.

18. The method of claim 5, wherein the only lubricant disposed between the first contact surface and the second contact surface is the gas-phase lubricant.

21. The method of claim 5, further comprising forming a sealed micromechanical device assembly, comprising sealing the micromechanical device in a processing region of a sealed enclosure after disposing the gas-phase lubricant between the first contact surface and the second contact surface, wherein the only lubricant disposed in the processing region of the sealed micromechanical device assembly is the gas-phase lubricant.

9. A method of operating a micromechanical device comprising:

providing a micromechanical device that comprises;

a first contact surface; and

a moveable component having a second contact surface, wherein the second contact surface interacts with the first contact surface during device operation;

causing the second contact surface of the moveable component to interact repeatedly with the first contact surface;

disposing a liquid or solid lubricant material on at least one of the first contact surface and the second contact surface; and

disposing a gas-phase lubricant between the first contact surface and the second contact surface at a predetermined pressure, wherein contaminants are removed from the micromechanical device assembly prior to disposing the gas-phase lubricant, and the gas-phase lubricant is adapted to reduce stiction between the first contact surface and the second contact surface.

10. The method of claim 9, wherein the gas-phase lubricant is a gas containing a haloalkane.

11. The method of claim 9, wherein the gas-phase lubricant is selected from a group consisting of sulfur hexafluoride, silicon tetrafluoride and perfluorocyclobutane.

12. The method of claim 9, wherein the gas-phase lubricant is a fluorinated compound that has a molecular weight greater than about 100 amu.

13. The method of claim 9, wherein the liquid or solid lubricant material is selected from a group consisting of dichlordimethylsilane, octadecyltrichlorsilane, perfluoroctyltrichlorsilane, perfluorodecanoic acid, perfluorodecyl-trichlorosilane, perfluoro-polyether and/or fluoroalkylsilane.

16. The method of claim 9, wherein the predetermined pressure is atmospheric pressure or greater.

19. The method of claim 9, wherein the only lubricant disposed between the first contact surface and the second contact surface is the gas-phase lubricant.

22. The method of claim 9, further comprising forming a sealed micromechanical device assembly, comprising sealing the micromechanical device in a processing region of a sealed enclosure after disposing the gas-phase lubricant between the first contact surface and the second contact surface, wherein the only lubricant disposed in the processing region of the sealed micromechanical device assembly is the gas-phase lubricant.