ELECTROMECHANICAL SYSTEM HAVING A DIELECTRIC MOVABLE MEMBRANE

• US 20090273824A1
• Filed: 07/06/2009
• Published: 11/05/2009
• Est. Priority Date: 05/09/2007
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Sasagawa, Teruo
• Granted Patent: US 7,889,417 B2
• Time in Patent Office: Days
• US Class Current: 359/291
• 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

An electromechanical device includes a partially reflective and partially transmissive layer and a movable functional element. The movable functional element includes a patterned flexible dielectric layer and a reflective layer mechanically coupled to the flexible dielectric layer. The patterned flexible dielectric layer is configured to flex in response to voltages applied to the partially reflective and partially transmissive layer to move the functional element in a direction generally perpendicular to the partially reflective and partially transmissive layer. The reflective layer is situated between the flexible dielectric layer and the partially reflective and partially transmissive layer.

Claims

1. An electromechanical device comprising:

a partially reflective and partially transmissive layer; and

a movable functional element comprising

a patterned flexible dielectric layer configured to flex in response to voltages applied to the partially reflective and partially transmissive layer to move the functional element in a direction generally perpendicular to the partially reflective and partially transmissive layer; and

a reflective layer mechanically coupled to the flexible dielectric layer, the reflective layer situated between the flexible dielectric layer and the partially reflective and partially transmissive layer.

2. The device of claim 1, wherein the flexible dielectric layer comprises SiON.

3. The device of claim 1, wherein the reflective layer is not spaced from the flexible dielectric layer.

4. The device of claim 1, wherein the partially reflective and partially transmissive layer comprises at least one of chromium and molybdenum-chromium.

5. The device of claim 1, wherein the movable functional element further comprises an aluminum layer coupled to the flexible dielectric layer on a side opposite to the reflective layer.

6. The device of claim 1, further comprising a plurality of posts supporting the functional element, wherein a coefficient of thermal expansion of the flexible dielectric layer is substantially similar to a coefficient of thermal expansion of the posts.

7. The device of claim 6, wherein the flexible dielectric layer comprises a dielectric material and wherein the plurality of supports comprises the dielectric material.

8. The device of claim 1, wherein the flexible dielectric layer is patterned by etching portions of a dielectric layer.

9. An electromechanical device comprising:

an optical stack;

a plurality of movable elements spaced from each other, each of the movable elements comprising

a flexible dielectric layer that flexes in response to voltages applied to the optical stack to move the movable element towards the optical stack; and

a reflective layer mechanically coupled to the flexible dielectric layer and situated between the flexible dielectric layer and the optical stack.

10. The device of claim 9, wherein each of the flexible dielectric layers comprises SiON.

11. The device of claim 9, wherein each of the reflective layers is in substantially continuous contact with the flexible dielectric layer.

12. The device of claim 9, wherein the optical stack comprises a partially reflective layer and partially transmissive layer, wherein the flexible dielectric layer flexes in response to voltages applied to the partially reflective layer and partially transmissive layer to move the movable element towards the partially reflective layer and partially transmissive layer.

13. The device of claim 9, wherein each of the flexible dielectric layers comprises a first side and a second side opposite to the first side, each of the reflective layers adjacent to the first side of the flexible dielectric layer, and wherein each of the movable elements further comprises an aluminum layer adjacent to the second side of the flexible dielectric layer.

14. The device of claim 9, further comprising a plurality of posts supporting the plurality of movable elements, wherein a coefficient of thermal expansion of each of the flexible dielectric layers is substantially similar to a coefficient of thermal expansion of the posts.

15. The device of claim 14, wherein the flexible dielectric layers and the plurality of posts comprise a same dielectric material.

16. An electromechanical device comprising:

a plurality of rows of actuation electrodes;

a plurality of columns of functional elements substantially orthogonal to the plurality of rows of actuation electrodes and crossing the plurality of rows of actuation electrodes at a plurality of active areas, each of the columns of functional elements comprising

a dielectric layer continuously extending along a length of the column, the dielectric layer configured to flex in response to voltages applied to the electrode at one of the active areas to move the functional element towards the actuation electrode of the one of the active areas; and

a reflective layer continuously extending along the length of the column between the dielectric layer and the actuation electrodes.

17. The device of claim 16, wherein each of the dielectric layers comprises SiON.

18. The device of claim 16, wherein each of the reflective layers is adjacent to the dielectric layer.

19. The device of claim 16, wherein the plurality of rows of actuation electrodes comprise partially reflective and partially transmissive layers, the dielectric layer configured to flex in response to voltages applied to the partially reflective and partially transmissive layer at one of the active areas to move the functional element towards the actuation partially reflective and partially transmissive layer of the one of the active areas.

20. The device of claim 16, wherein each of the movable functional elements comprises a second reflective layer adjacent to the dielectric layer on a side opposite to the reflective layer.

21. The device of claim 16, further comprising a plurality of posts supporting the plurality of columns of functional elements, wherein each of the dielectric layers has a coefficient of thermal expansion and each of the plurality of posts has a substantially similar coefficient of thermal expansion.