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

• US 7,952,786 B2
• Filed: 04/23/2008
• Issued: 05/31/2011
• 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: Xiong, Fulin, Chen, Dongmin
• Primary Examiner(s): Mack; Ricky L
• Assistant Examiner(s): Thomas; Brandi N
• Application Number:
  US12/108,030
• Publication Number:
  US 20090284823A1
• Time in Patent Office: 1,133 Days
• Field of Search: 359290-292, 359/295, 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, and a coating of liquid or solid lubricant on at least one of the contact surfaces, where the second contact surface interacts with the first contact surface during device operation, and a gas-phase lubricant is disposed between the first contact surface and the second contact surface, where the gas-phase lubricant is adapted to increase the usable lifetime of the liquid or solid lubricant coating on the contact surfaces. 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 used with conventional solid or liquid lubricants is more reliable than solid or liquid lubricants used alone in preventing stiction-related device failures.

Claims

1. A method of operating a micromechanical device comprising:

biasing one or more electrodes, wherein biasing the one or more electrodes causes a moveable component having a first contact surface to interact with a second contact surface;

biasing the one or more electrodes repeatedly until a stiction force prevents the first contact surface from being separated from the second contact surface; and

separating the first contact surface from the second contact surface by exposing the first and second contact surfaces to a gas-phase lubricant.

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 tetrafluoride 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.

5. The method of claim 1, wherein the moveable component comprises a mirror.

6. The method of claim 1, wherein the micromechanical device is an optical image processor or a spatial light modulator.