MEMS device

• US 6,809,848 B2
• Filed: 06/01/2001
• Issued: 10/26/2004
• Est. Priority Date: 06/01/2001
• Status: Expired due to Term

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Agere Systems Incorporated (Broadcom, Inc.)
• Inventors: Fang, Lu, Carr, Charles D, Malkani, Dhiraj H
• Primary Examiner(s): Dunn, Drew A.
• Assistant Examiner(s): Pritchett, Joshua L
• Application Number:
  US09/872,306
• Publication Number:
  US 20020181847A1
• Time in Patent Office: 1,243 Days
• Field of Search: 385/18, 385/14, 359/223, 359/224, 359/225, 359/226, 310/309
• US Class Current: 359/196.1
• CPC Class Codes: G02B 2006/12104 Mirror; Reflectors or the like
• CPC Class Codes: G02B 6/3518 the reflective optical element being an intrinsic part of a MEMS device, i.e. fabricated together with the MEMS device MEMS devices in general B81B; manufacture of MEM devices in general B81C; micromechanical devices controlling the direction of light G02B26/0833
• CPC Class Codes: G02B 6/357 Electrostatic force electrostatic forces controlling reflecting elements in general G02B26/0841
• CPC Class Codes: G02B 6/3584 constructional details of an associated actuator having a MEMS construction, i.e. constructed using semiconductor technology such as etching MEMS per se B81B, B81C

Abstract

The invention is a device and method of fabrication where an array of electrostatically activated members of (e.g., movable mirrors) formed in a layer comprising silicon is mounted over a ceramic substrate. The substrate includes conductors formed on a major surface and in via holes formed in the substrate. The conductors are positioned so as to selectively operate the array of mirrors.

Claims

1. A device comprising:

an array of electrostatically activated members formed in a layer comprising silicon; and

a substrate comprising a ceramic material and including conductors formed on a major surface thereof and in via holes formed therethrough the conductors being positioned with respect to and separate from the silicon layer so as to selectively operate the array of members using an electrostatic force such that the utilization of conductors on the silicon layer is not required.

2. The device according to claim 1 wherein the members are rotatable mirrors.

3. The device according to claim 2 wherein the mirrors are adapted to rotate about at least two axes.

4. The device according to claim 1 wherein the array comprises a structure of at least eight members by at least ten members.

5. The device according to claim 1 wherein the array is separated from the ceramic substrate by a spacer layer.

6. The device according to claim 1 further comprising a layer of metal on a major surface of the silicon layer.

7. The device according to claim 1 wherein the ceramic substrate comprises aluminum nitride (AlN).

8. The device according to claim 1 wherein the substrate has a flatness of less than or equal to 10 microns.

9. The device according to claim 1 wherein the substrate has a surface roughness of less than or equal to 1 micron.

10. The device according to claim 1 wherein the conductors have a line width of less than 2 microns and a spacing less than 2 microns.

11. The device according to claim 1 wherein the conductors positioned to operate one member from the array of electrostatically activated members comprise an array of at least four conductors extending through separate via holes.

12. A device comprising:

an array of at least 8×

10 mirrors rotatable about at least two axes formed in a layer comprising silicon;

a spacer layer formed over a surface of the silicon layer; and

a substrate comprising a ceramic material having a flatness of less than or equal to 10 microns and a surface roughness of less than or equal to 1 micron, said substrate including conductors formed on a major surface thereof and in via holes formed therethrough, the conductors being positioned with respect to the silicon layer so as to selectively operate the array of mirrors using an electrostatic force, wherein the conductors remain separated from said silicon layer and are positioned to operate a mirror comprise an array of at least four conductors extending through separate via holes.

13. A method of forming a device comprising:

forming an array of electrostatically activated members in a layer of silicon; and

mounting said silicon layer over a substrate comprising a ceramic material which includes conductors formed on a major surface of the substrate and in via holes formed in the substrate, the silicon layer being mounted so as to position the members with respect to the conductors to permit selective operation of the members.

14. The method according to claim 13 wherein the members are movable mirrors.

15. The method according to claim 13 wherein the silicon layer is mounted using an epoxy bond.

16. The method according to claim 13 wherein the silicon layer is mounted using a solder bond.

17. The method according to claim 13 wherein a spacer layer is included between the silicon layer and the ceramic substrate.