Shaped electrodes for micro-electro-mechanical-system (MEMS) devices to improve actuator performance and methods for fabricating the same Number:6,825,967 from the United States Patent and Trademark Office (PTO) owispatent Shaped electrodes for micro-electro-mechanical-system (MEMS) devices to improve actuator performance and methods for fabricating the same are disclosed. The shaped electrodes utilize its three-dimensional geometry to shape an electric field for electrostatic actuation for MEMS devices. For example, the height, width, length, sidewall slope, and layout of the shaped electrodes can be used to provide an optimum electric field in moving a MEMS mirror device. The shaped electrodes can provide electrostatic actuation at a low operating voltage and provide an optimum electric field for maximum tilt or angular range of motion for a MEMS mirror device. The shaped electrodes can be fabricated simply by using a pillar wafer and an electrode wafer. The pillar wafer can be used to form pillars as electrodes, or, alternatively, as barriers. A single substrate can also be used to form pillars and electrodes.<H fabricating, performance, Shaped, electrod, 6825967.html, Patent, pto, 6825967

Title: Shaped electrodes for micro-electro-mechanical-system (MEMS) devices to improve actuator performance and methods for fabricating the same

Abstract: Shaped electrodes for micro-electro-mechanical-system (MEMS) devices to improve actuator performance and methods for fabricating the same are disclosed. The shaped electrodes utilize its three-dimensional geometry to shape an electric field for electrostatic actuation for MEMS devices. For example, the height, width, length, sidewall slope, and layout of the shaped electrodes can be used to provide an optimum electric field in moving a MEMS mirror device. The shaped electrodes can provide electrostatic actuation at a low operating voltage and provide an optimum electric field for maximum tilt or angular range of motion for a MEMS mirror device. The shaped electrodes can be fabricated simply by using a pillar wafer and an electrode wafer. The pillar wafer can be used to form pillars as electrodes, or, alternatively, as barriers. A single substrate can also be used to form pillars and electrodes.

Patent Number: 6,825,967 Issued on 11/30/2004 to Chong, et al.

Inventors: Chong; John (Santa Barbara, CA); Lee; Seung Bok (Ithaca, NY); MacDonald; Noel (Santa Barbara, CA); Lewis; Robert (Santa Barbara, CA); Hunt; Peter (Scotts Valley, CA)
Assignee: Calient Networks, Inc. (San Jose, CA)

Appl. No.: 676459

Filed: September 29, 2000

Current U.S. Class: 359/290 ; 359/293; 359/295; 359/900

Field of Search: 359/290,291,295,298,293,294,900

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Primary Examiner: Epps; Georgia
Assistant Examiner: Tra; Tuyen
Attorney, Agent or Firm: Blakely, Sokoloff, Taylor & Zafman LLP

Claims

What is claimed is:

1. A method of fabricating a micro-electro-mechanical-system (MEMS) device, the method comprising: attaching a pillar wafer to an electrode wafer; and forming one or more pillars from the pillar wafer, wherein forming the shaped pillars includes forming "L" shaped pillars, slanted shaped pillars, curved shaped pillars, or pillars with slots formed therein.

2. The method of claim 1, further comprising: forming one or more gimbaled mirror devices on the electrode wafer such that the pillars are to provide an electric field or to provide a barrier.

3. A method of fabricating a micro-electro-mechanical-system (MEMS) device, the method comprising: forming a plurality of trenches in a first side of a substrate; forming an insulator in the plurality of trenches and on the first side of the substrate such that the insulator defines exposed areas of the first side of the substrate; forming a metal line on the insulator and exposed areas of the first side of the substrate; and removing selectively portions of a second side of the substrate to form pillars connected with the insulator and metal line.

4. The method of claim 3, wherein removing selectively portions of the second side of the substrate includes forming shaped pillars.

5. The method of claim 3, wherein removing selectively portions of the second side of the substrate includes forming "L" shaped pillars, slanted shaped pillars, curved shaped pillars, or pillars with slots formed therein.

6. The method of claim 3, wherein forming the metal line includes forming a discontinuous metal line.

7. The method of claim 3, further comprising: forming one or more gimbaled mirror devices on the substrate such that the pillars are to provide an electric field or to provide a barrier.

Description

FIELD OF THE INVENTION

The present invention relates generally to micro-electro-mechanical-system (MEMS) devices. More particularly, the p