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

• US 20080041817A1
• Filed: 10/26/2007
• Published: 02/21/2008
• Est. Priority Date: 09/30/2003
• Status: Abandoned Application

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Lin, Wen-Jian
• Application Number:
  US11/925,477
• Publication Number:
  US 20080041817A1
• Time in Patent Office: Days
• US Class Current: 216/24
• 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 method of manufacturing an optical interference display cell, comprising:

forming a first electrode on a substrate;

forming a sacrificial layer on the first electrode;

forming a first material layer on the sacrificial layer;

forming a conductor layer comprising a light reflective surface on the first material layer, wherein the conductor layer is susceptible to etching by an etchant;

defining the conductor layer and the first material layer to form a second electrode; and

removing the sacrificial layer using the etchant, wherein the first material layer protects the light reflective surface from the etchant, wherein the optical interference display cell formed after removal of the sacrificial layer is configured to interferometrically reflect light entering the cavity and contacting the light reflective surface.

2. The method of claim 1, wherein the sacrificial layer is selected from the group consisting of metal material and silicon material.

3. The method of claim 1, wherein the first material layer is selected from the group consisting of silicon material, dielectric material, transparent conductor material, macromolecule polymer, metal oxide and any arbitrary combination thereof.

4. The method of claim 3, wherein the first material layer is poly-silicon or amorphous silicon.

5. The method of claim 3, wherein the first material layer is silicon oxide, silicon nitride, or silicon oxynitride.

6. The method of claim 3, wherein the first material layer is indium tin oxide, indium zinc oxide, or indium oxide.

7. The method of claim 3, wherein the first material layer is paraffin.

8. The method of claim 1, wherein the thickness of the first material layer is about several angstroms to 2000 angstrom.

9. The method of claim 1, wherein the thickness of the first material layer is about 200 angstrom to 1000 angstrom.

10. The method of claim 1, comprising:

forming at least two openings in the sacrificial layer and the first electrode; and

forming a supporter in the opening.

11. The method of claim 10, wherein the supporter is selected from the group consisting of positive photoresists, negative photoresists, acrylic resins, and epoxy resins.

12. A method of manufacturing an optical interference display cell, comprising:

forming a first electrode on a substrate;

forming a sacrificial layer on the first electrode;

forming a first material layer on the sacrificial layer;

forming a conductor layer comprising a light reflective surface on the first material layer, wherein the conductor layer is susceptible to etching by an etchant;

forming a second material layer on the conductor layer;

defining the second material layer, the conductor layer and the first material layer to form a second electrode; and

removing the sacrificial layer using the etchant, wherein the first material layer protects the light reflective surface from the etchant, wherein the optical interference display cell formed after removal of the sacrificial layer is configured to interferometrically reflect light entering the cavity and contacting the light reflective surface.

13. The method of claim 12, comprising, after defining the second material layer, the conductor layer and the first material layer:

forming a third material layer covering the second electrode; and

forming a spacer on the sidewall of the second electrode.

14. The method of claim 13, wherein the third material layer is selected from the group consisting of silicon material, dielectric material, transparent conductor material, macromolecule polymer, metal oxide and any arbitrary combination thereof.

15. The method of claim 14, wherein the third material layer is poly-silicon or amorphous silicon.

16. The method of claim 14, wherein the third material layer is silicon oxide, silicon nitride, or silicon oxynitride.

17. The method of claim 14, wherein the third material layer is paraffin.

18. The method of claim 12, wherein the sacrificial layer is selected from the group consisting of metal material and silicon material.

19. The method of claim 12, wherein the first and second material layers are selected from the group consisting of silicon material, dielectric material, transparent conductor material, macromolecule polymer, metal oxide and any arbitrary combination thereof.

20. The method of claim 19, wherein the first and second material layers are poly-silicon or amorphous silicon.

21. The method of claim 19, wherein the first and second material layers are silicon oxide, silicon nitride, or silicon oxynitride.

22. The method of claim 19, wherein the first and second material layers are paraffin.

23. The method of claim 12, wherein the thickness of the first and second material layers are about several angstroms to 2000 angstrom.

24. The method of claim 12, wherein the thickness of the first and second material layers are about 200 angstrom to 1000 angstrom.

25. The method of claim 12, comprising:

forming at least two openings in the sacrificial layer and the first electrode; and

forming a supporter in the opening.