STRUCTURE OF A MICRO ELECTRO MECHANICAL SYSTEM AND THE MANUFACTURING METHOD THEREOF

• US 20080055699A1
• Filed: 10/26/2007
• Published: 03/06/2008
• Est. Priority Date: 09/30/2003
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Lin, Wen-Jian
• Granted Patent: US 7,709,964 B2
• Time in Patent Office: Days
• US Class Current: 359/254
• CPC Class Codes: B81B 2201/047 Optical MEMS not provided for in B81B2201/042 - B81B2201/045
• CPC Class Codes: B81C 1/00801 Avoid alteration of functional structures by etching, e.g. using a passivation layer or an etch stop layer B81C1/00595, B81C1/00468 take precedence
• CPC Class Codes: G02B 26/001 based on interference in an adjustable optical cavity interference filters G02B5/28; devices or arrangements using multiple reflections in spectrometry or monochromators G01J3/26
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means

Abstract

A structure of a micro electro mechanical system and a manufacturing method are provided, the structure and manufacturing method is adapted for an optical interference display cell. The structure of the optical interference display cell includes a first electrode, a second electrode and posts. The second electrode comprises a conductive layer covered by a material layer and is arranged about parallel with the first electrode. The support is located between the first plate and the second plate and a cavity is formed. In the release etch process of manufacturing the structure, the material layer protects the conductive layer from the damage by an etching reagent. The material layer also protects the conductive layer from the damage from the oxygen and moisture in the air.

Claims

1. A pre-release structure configured to form an optical interference display cell upon removal of a sacrificial layer, the pre-release structure comprising:

a first electrode;

a sacrificial layer;

a first material layer; and

a conductor layer comprising a light reflective surface;

wherein;

the sacrificial layer is positioned between the first electrode and the first material layer;

the first material layer is positioned between the sacrificial layer and the conductor layer;

the conductor layer is susceptible to etching by an etchant suitable to remove the sacrificial layer;

the first material layer is adapted to protect the light reflective layer from etching when the sacrificial layer is removed using the etchant; and

the optical interference display cell formed after removal of the sacrificial layer is configured to interferometrically reflect light contacting the light reflective surface.

2. The pre-release structure of claim 1, wherein the first electrode is selected from the group consisting of a narrowband mirror, a broadband mirror, a non-metal mirror, a metal mirror, and any arbitrary combination thereof.

3. The pre-release structure of claim 1, wherein the first electrode is a metal.

4. The pre-release structure of claim 1, wherein the first electrode is a non-metal.

5. The pre-release structure of claim 1, wherein the conductor layer is selected from the group consisting of a narrowband mirror, a broadband mirror, a non-metal mirror, a metal mirror, and any arbitrary combination thereof.

6. The pre-release structure of claim 1, wherein the conductor layer is a metal.

7. The pre-release structure of claim 1, wherein the conductor layer is a non-metal.

8. The pre-release structure of claim 1, wherein the sacrificial layer comprises a metal material or a silicon material.

9. The pre-release structure of claim 8, wherein the sacrificial layer comprises amorphous silicon.

10. The pre-release structure of claim 8, wherein the sacrificial layer comprises poly-silicon.

11. The pre-release structure of claim 1, wherein the first material layer is selected from the group consisting of a silicon material, a dielectric material, a transparent conductor material, a macromolecule polymer, a metal oxide, and any arbitrary combination thereof.

12. The pre-release structure of claim 11, wherein the first material layer is a silicon material.

13. The pre-release structure of claim 12, wherein the first material layer is poly-silicon or amorphous silicon.

14. The pre-release structure of claim 12, wherein the first material layer is silicon oxide.

15. The pre-release structure of claim 12, wherein the first material layer is silicon nitride.

16. The pre-release structure of claim 1, wherein the thickness of the first material layer is about several angstroms to 2000 angstrom.

17. The pre-release structure of claim 1, wherein the thickness of the first material layer is about 200 angstrom to 1000 angstrom.

18. The pre-release structure of claim 1, further comprising a second material layer, wherein the conductor layer is positioned between the first material layer and the second material layer.

19. The pre-release structure of claim 18, wherein the second material layer is selected from the group consisting of a silicon material, a dielectric material, a transparent conductor material, a macromolecule polymer, a metal oxide, and any arbitrary combination thereof.

20. The pre-release structure of claim 1, further comprising a supporter configured to separate the first electrode from the first material layer to form a cavity upon structure release etching.

21. The pre-release structure of claim 19, wherein the supporter is selected from the group consisting of a silicon material, a dielectric material, a transparent conductor material, a macromolecule polymer, a metal oxide, and any arbitrary combination thereof.

22. The method of claim 20, wherein the supporter is selected from the group consisting of positive photoresists, negative photoresists, acrylic resins, and epoxy resins.