Method for forming a planar mirror using a sacrificial oxide

• US 20060024620A1
• Filed: 07/30/2004
• Published: 02/02/2006
• Est. Priority Date: 07/30/2004
• Status: Active Grant

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Nikkel, Eric L., Monroe, Michael G., Szepesi, Mickey
• Granted Patent: US 7,273,693 B2
• Time in Patent Office: Days
• US Class Current: 430/321
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means

Abstract

A micro electromechanical system (MEMS) mirror, comprising a displaceable hinged member, a mirror plate, and a plurality of mirror support elements. The mirror plate has a planar mirror face affixed thereto. The plurality of mirror support elements extend between the displaceable hinged member and the mirror plate.

Claims

1. A method for making a micro mirror device, the method comprising:

forming a mirror actuator;

depositing a first sacrificial oxide layer above the mirror actuator;

depositing a hinged member at least partially on the first sacrificial oxide layer;

depositing a second sacrificial oxide layer at least partially above the hinged member;

forming voids in the second sacrificial oxide layer, the voids extend from the hinged member to an upper surface of the second sacrificial oxide layer;

forming metal vias in the voids that extend from the hinged member to the upper surface of the second sacrificial oxide layer;

forming a mirror plate on the upper surface of the sacrificial layer that are secured to the metal vias; and

removing the first sacrificial oxide layer and the second sacrificial oxide layer to leave behind the micro mirror device formed including the hinged member, the metal vias, and the mirror plate.

2. The method of claim 1, further comprising planarizing the surface of the mirror plate.

3. The method of claim 1, further comprising depositing a substantially planar mirror face layer on the mirror plate.

4. The method of claim 1, further comprising forming a hinge in the hinged member.

5. The method of claim 1, wherein the second sacrificial oxide layer includes a silicon oxide.

6. The method of claim 1, wherein the metal via includes a plug, and wherein a portion of the plug forms a planar surface that is substantially planar with the mirror plate, and wherein this substantially planar surface provides for the maintaining the mirror plate in its substantially planar configuration.

7. The method of claim 1, further comprising forming an integrated circuit portion, and further comprising forming the micro mirror device above the integrated circuit portion.

8. The method of claim 1, further comprising using the micro mirror device as a display device.

9. The method of claim 1, further comprising using the micro mirror device as a spatial light modulator.

10. A method for making a micro mirror device, the method comprising:

forming a hinged member;

depositing a sacrificial oxide layer at least partially above the hinged member;

forming voids in the sacrificial oxide layer, the voids extend from the hinged member to an upper surface of the sacrificial oxide layer;

forming metal vias in the voids that extend from the hinged member to the upper surface of the sacrificial oxide layer;

forming a mirror plate on the upper surface of the sacrificial layer that are secured to the metal vias; and

removing the sacrificial oxide layer to leave behind the micro mirror device formed including the hinged member, the metal vias, and the mirror plate.