MEMS device and method of forming MEMS device

• US 7,310,175 B2
• Filed: 12/21/2004
• Issued: 12/18/2007
• Est. Priority Date: 10/02/2003
• Status: Active Grant

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Nikkel, Eric L., Monroe, Michael G., Lazaroff, Dennis M.
• Primary Examiner(s): Loke; Steven
• Assistant Examiner(s): GOODWIN, DAVID J
• Application Number:
  US11/019,780
• Publication Number:
  US 20050106772A1
• Time in Patent Office: 1,092 Days
• Field of Search: 359/223, 359/291, 359/290, 257/415, 257/678
• US Class Current: 359/225.1
• CPC Class Codes: B81B 2201/042 Micromirrors, not used as optical switches
• CPC Class Codes: B81B 2203/0181 See-saws
• CPC Class Codes: B81B 2203/058 Rotation out of a plane parallel to the substrate
• CPC Class Codes: B81B 3/0083 Optical properties
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means
• CPC Class Codes: Y10S 359/904 Micromirror

Abstract

A method of forming a MEMS device includes depositing a conductive material on a substructure, forming a first sacrificial layer over the conductive material, including forming a substantially planar surface of the first sacrificial layer, and forming a first element over the substantially planar surface of the first sacrificial layer, including communicating the first element with the conductive material through the first sacrificial layer. In addition, the method includes forming a second sacrificial layer over the first element, including forming a substantially planar surface of the second sacrificial layer, forming a support through the second sacrificial layer to the first element after forming the second sacrificial layer, including, filling the support, and forming a second element over the support and the substantially planar surface of the second sacrificial layer. As such, the method further includes substantially removing the first sacrificial layer and the second sacrificial layer, thereby supporting the second element relative to the first element with the support.

Claims

1. A micro-mirror device, comprising:

a substructure;

conductive material patterned on the substructure;

a hinge element supported over the substructure and communicated with the conductive material;

a reflective element supported over the hinge element; and

a support extended between the hinge element and the reflective element,

wherein the support includes a protective material forming a cavity open to the reflective element and a plug material filling the cavity, wherein a surface of the protective material and a surface of the plug material form a substantially planar surface, wherein the reflective element is formed over the substantially planar surface, and contacts the protective material and the plug material, and wherein the plug material is enclosed by the reflective element and the protective material.

2. The device of claim 1, wherein the reflective element has a substantially planar surface over an entirety thereof.

3. The device of claim 1, further comprising:

a first sacrificial layer formed over the conductive material, wherein the hinge element is adapted to be formed over the first sacrificial layer; and

a second sacrificial layer formed over the hinge element, wherein the reflective element is adapted to be formed over the second sacrificial layer,

wherein the first sacrificial layer and the second sacrificial layer are adapted to be removed by an etch process after the hinge element and the reflective element are formed.

4. The device of claim 3, wherein the etch process includes a dry etch process.

5. The device of claim 3, wherein the second sacrificial layer is adapted to have an opening formed therein to the hinge element, wherein the support is adapted to be formed in the opening and filled with the plug material before the reflective element is formed over the second sacrificial layer, and wherein the reflective element is adapted to be formed over the second sacrificial layer and the plug material.

6. The device of claim 5, wherein the plug material is adapted to be planarized before the reflective element is formed over the second sacrificial layer and the plug material.

7. The device of claim 3, wherein the first sacrificial layer and the second sacrificial layer include one of silicon, an oxide, and photoresist.

8. The device of claim 1, wherein the plug material includes one of silicon, an oxide, a metal, and photoresist.

9. The device of claim 1, wherein the support constitutes a conductive via extended between the hinge element and the reflective element.

10. The device of claim 1, wherein the substructure includes a base material and at least one conductive layer formed on the base material, wherein the conductive material communicates with the at least one conductive layer of the substructure.

11. The device of claim 10, wherein the base material of the substructure includes silicon and the at least one conductive layer of the substructure includes aluminum.

12. The device of claim 1, wherein the substructure includes a complementary metal oxide semi-conductor structure.

13. A display device including the micro-mirror device of claim 1.

14. The device of claim 1, wherein the hinge element includes a yoke and hinges extended from the yoke, wherein the hinges support the yoke, and the yoke supports the support and the reflective element.

15. A micro-mirror device, comprising:

a substructure;

conductive material patterned on the substructure;

a hinge element extended over the substructure and communicated with the conductive material;

a reflective element extended over the hinge element; and

means for supporting the reflective element relative to the hinge element, including means for forming a cavity open to the reflective element, and means for filling the cavity,

wherein a surface of the means for forming the cavity and a surface of the means for filling the cavity form a substantially planar surface for supporting the reflective element, wherein the reflective element is formed over the substantially planar surface, and contacts the means for forming the cavity and the means for filling the cavity, wherein the means for filling the cavity is enclosed by the reflective element and the means for forming the cavity, and wherein the reflective element has a substantially planar surface over an entirety thereof.

16. The device of claim 15, wherein means for supporting the reflective element includes a support extended between the hinge element and the reflective element, wherein the support forms the cavity open to the reflective element.

17. The device of claim 16, wherein the support constitutes a conductive via extended between the hinge element and the reflective element.

18. The device of claim 15, wherein means for supporting the reflective element includes a plug material filled within the cavity, wherein the reflective element is formed over and contacts the plug material.

19. The device of claim 18, wherein the plug material includes one of silicon, an oxide, a metal, and photoresist.

20. The device of claim 15, wherein the hinge element includes a yoke and hinges extended from the yoke, wherein the hinges support the yoke, and the yoke supports the means for supporting the reflective element and the reflective element.

21. A micro-mirror device, comprising:

a substructure;

conductive material patterned on the substructure;

a hinge element supported over the substructure and communicated with the conductive material;

a reflective element supported over the hinge element; and

a support extended between the hinge element and the reflective element,

wherein the support includes a conductive via open to the reflective element and a plug material filling the conductive via, wherein a surface of the conductive via and a surface of the plug material form a substantially planar surface of the support, wherein the reflective element is formed over the substantially planar surface of the support, and contacts the surface of the conductive via and the surface of the plug material, and wherein the plug material is enclosed by the reflective element and the conductive via.

22. The device of claim 21, wherein the reflective element has a substantially planar surface over an entirety thereof.

23. The device of claim 21, wherein the hinge element includes a yoke and hinges extended from the yoke, wherein the hinges support the yoke, and the yoke supports the support and the reflective element.