Lubricating micro-machined devices using fluorosurfactants

• US 7,291,363 B2
• Filed: 07/01/2002
• Issued: 11/06/2007
• Est. Priority Date: 06/30/2001
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Miller, Seth
• Primary Examiner(s): Bashore; Alain L.
• Application Number:
  US10/186,411
• Publication Number:
  US 20030002019A1
• Time in Patent Office: 1,954 Days
• Field of Search: 427/421.1, 427/427.4, 427/427.5, 438/38
• US Class Current: 427/421.1
• CPC Class Codes: B81B 3/0005 Anti-stiction coatings
• CPC Class Codes: G03B 21/008 using micromirror devices
• CPC Class Codes: Y10T 29/49004 including measuring or testing of device or component part

Abstract

A method of lubricating MEMS devices using fluorosurfactants 42. Micro-machined devices, such as a digital micro-mirror device (DMD™) 940, which make repeated contact between moving parts, require lubrication in order to prevent the onset of stiction (static friction) forces significant enough to cause the parts to stick irreversibly together, causing defects. These robust and non-corrosive fluorosurfactants 42, which consists of a hydrophilic chain 40 attached to a hydrophobic fluorocarbon tail 41, are applied by nebulization and replace the more complex lubricating systems, including highly reactive PFDA lubricants stored in polymer getters, to keep the parts from sticking. This lubrication process, which does not require the use of getters, is easily applied and has been shown to provide long-life, lower-cost, operable MEMS devices.

Claims

1. A method of lubricating a MEMS device, comprising the steps of:

nebulizing a fluorosurfactant comprising a hydrophilic portion attached to a hydrophobic fluorocarbon portion; and

exposing a MEMS device to said nebulized fluorosurfactant.

2. The method of claim 1, wherein:

said hydrophilic portion of a majority of said fluorosurfactant align toward a surface of said MEMS device.

3. The method of claim 1, wherein said fluorosurfactant remains a liquid on said MEMS device.

4. The method of claim 1, wherein said fluorosurfactant is non-corrosive to the surfaces of said MEMS device.

5. The method of claim 1, wherein:

said hydrophobic fluorocarbon portions of a majority of said fluorosurfactant align away from a surface of said MEMS device.

6. The method of claim 1, wherein said fluorosurfactant coats contact regions of said MEMS device.

7. The method of claim 1, wherein said hydrophobic fluorocarbon includes fluorine.

8. The method of claim 1, wherein said hydrophobic fluorocarbon includes hydrogen.

9. The method of claim 1, wherein exposing said MEMS device comprises exposing a micromirror to said nebulized fluorosurfactant.

10. The method of claim 1, comprising enclosing said packaging said MEMS device.

11. A method of lubricating a MEMS device comprising:

nebulizing a fluorosurfactant comprising a hydrophilic portion attached to a hydrophobic fluorocarbon; and

exposing a MEMS device to said nebulized fluorosurfactant to coat contacting portions of said MEMS device with said fluorosurfactant.

12. The method of claim 11, wherein:

said hydrophobic fluorocarbon portions of a majority of said fluorosurfactant align away from a surface of said MEMS device.