Elimination of sticking of micro-mechanical devices

• US 5,412,186 A
• Filed: 02/23/1994
• Issued: 05/02/1995
• Est. Priority Date: 02/23/1994
• Status: Expired due to Term

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Gale, Richard O.
• Primary Examiner(s): Leung, Philip H.
• Application Number:
  US08/200,260
• Time in Patent Office: 433 Days
• Field of Search: 219/678, 219/679, 219/696, 219/745, 219/750, 359/224, 359/230, 359/900
• US Class Current: 219/679
• CPC Class Codes: B81B 2201/042 Micromirrors, not used as optical switches
• 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 1/00976 Control methods for avoiding stiction, e.g. controlling the bias voltage
• CPC Class Codes: G02B 26/0833 the reflecting element being a micromechanical device, e.g. a MEMS mirror, DMD G02B26/0825 takes precedence; micromechanical devices in general B81B
• CPC Class Codes: H05B 6/80 Apparatus for specific applications stoves or ranges F24C7/02
• CPC Class Codes: Y10S 359/90 Methods

Abstract

A method of preventing sticking of moving parts of a micro-mechanical device. A set of microwave frequencies, which will cause water molecules to resonate, is determined. From this set of frequencies, an applied frequency that will provide an efficient energy coupling from the source to the device is selected. The device is continuously irradiated with radiation of this frequency.

Claims

1. A method of preventing sticking of contacting elements of a micro-mechanical device, comprising the steps of:

determining a set of electromagnetic microwave frequencies that when applied to said contacting elements, will cause said radiation to become absorbed by water molecules on the surface of said contacting elements;

selecting from said set of electromagnetic microwave frequencies, an applied frequency that provides a desired energy coupling to said contacting elements; and

irradiating said contacting elements with radiation having said applied frequency, using a microwave source.

2. The method of claim 1, wherein said irradiating step is performed while said device is in operation.

3. The method of claim 1, wherein said irradiating step is performed while said device is not in operation.

4. The method of claim 1, wherein said applied frequency is 2.45 gigahertz.

5. The method of claim 1, wherein said irradiating step is performed with a waveguide that provide a directed beam of said radiation.

6. The method of claim 1, further comprising the step of placing said device into a resonant cavity prior to said irradiating step.

7. The method of claim 1, wherein said determining step is accomplished by analyzing the water bonding properties of said contacting elements.

8. The method of claim 1, wherein said microwave source is a magnetron.