ELECTROMECHANICAL DEVICES AND METHODS OF FABRICATING SAME

• US 20090323168A1
• Filed: 06/22/2009
• Published: 12/31/2009
• Est. Priority Date: 09/20/2002
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: IDC, LLC
• Inventors: Chui, Clarence, Miles, Mark W., Kothari, Manish, Batey, John
• Granted Patent: US 8,368,124 B2
• Time in Patent Office: Days
• US Class Current: 359/290
• CPC Class Codes: B81B 3/0035 Constitution or structural means for controlling the movement of the flexible or deformable elements
• 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

Abstract

In one embodiment, the invention provides a method for fabricating a microelectromechanical systems device. The method comprises fabricating a first layer comprising a film having a characteristic electromechanical response, and a characteristic optical response, wherein the characteristic optical response is desirable and the characteristic electromechanical response is undesirable; and modifying the characteristic electromechanical response of the first layer by at least reducing charge build up thereon during activation of the micro electromechanical systems device.

Claims

1. An apparatus, comprising:

a substrate;

an electrode, wherein the electrode is located over the substrate;

an additional layer located over the electrode, wherein the additional layer comprises SiO₂.

an etch barrier layer, wherein the etch barrier layer is located over the additional layer;

an air gap, wherein the air gap is located adjacent the etch barrier layer; and

a displaceable layer, wherein the displaceable layer is reflective to incident light.

2. The apparatus of claim 1, wherein the etch barrier layer is resistant to XeF₂.

3. The apparatus of claim 1, wherein the etch barrier layer comprises Al₂O₃.

4. The apparatus of claim 1, wherein the apparatus is an interferometric modulator.

5. The apparatus of claim 1, wherein the displaceable layer is electrostatically displaceable.

6. The apparatus of claim 1, wherein the displaceable layer is displaceable through the air gap.

7. The apparatus of claim 1, wherein the additional layer is substantially transparent.

8. A method of making an electromechanical device, comprising:

forming an electrode layer over a substrate;

forming an additional layer over the electrode layer, wherein the additional layer comprises SiO₂;

forming an etch barrier layer over the transparent layer; and

exposing the etch barrier layer to a chemical etchant, wherein the etch barrier layer is resistant to the chemical etchant.

9. The method of claim 8, wherein the etch barrier layer comprises Al₂O₃.

10. The method of claim 8, wherein the chemical etchant comprises XeF₂.

11. The method of claim 8, additionally comprising forming a displaceable layer, wherein the displaceable layer is separated from the etch barrier layer by an air gap.

12. The method of claim 8, wherein the MEMS device is an interferometric modulator.

13. The method of claim 8, wherein the additional layer is substantially transparent.

14. An electromechanical device comprising:

a substrate;

an electrode, wherein the electrode is located on the substrate;

an air gap;

an additional layer, wherein the additional layer comprises SiO₂, and wherein the additional layer is located between the electrode and the air gap; and

an etch barrier layer comprising Al₂O₃, wherein the etch barrier layer is located between the air gap and the additional layer.

15. The device of claim 14, farther comprising an electrostatically displaceable layer located on the opposite side of the air gap from the electrode.

16. The apparatus of claim 14, additionally comprising a layer comprising Al₂O₃ located between the additional layer and the electrode.

17. The device of claim 14, wherein the device is an interferometric modulator.

18. The device of claim 14, wherein the etch barrier layer is located on of adjacent the additional layer.