Method and apparatus for providing a light absorbing mask in an interferometric modulator display

• US 7,916,378 B2
• Filed: 03/08/2007
• Issued: 03/29/2011
• Est. Priority Date: 03/08/2007
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Wang, Chun-Ming Albert
• Primary Examiner(s): Mack; Ricky L
• Assistant Examiner(s): PINKNEY, DAWAYNE
• Application Number:
  US11/683,787
• Publication Number:
  US 20080218834A1
• Time in Patent Office: 1,482 Days
• Field of Search: 359/247, 359/245, 359260-261, 359/298, 359301-303, 359317-318, 359/577, 359290-292, 359223-225, 359262-263, 359/295, 359/198
• US Class Current: 359/247
• 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

A microelectromechanical system (MEMS) is provided. In one embodiment, the MEMS includes a transparent substrate, and a plurality of interferometric modulators. The plurality of interferometric modulators includes an optical stack coupled to the transparent substrate, in which the optical stack includes a first light absorbing area. The plurality of interferometric modulators further includes a reflective layer over the optical stack, and one or more posts to support the reflective layer. Each of the one or more posts includes a second light absorbing area integrated in the post.

Claims

1. An electromechanical system comprising:

a transparent substrate; and

a plurality of interferometric modulators comprising;

an optical stack coupled to the transparent substrate, the optical stack comprising;

a first light absorbing layer; and

a conducting layer comprising a partially reflective layer, said conducting layer separate from the first light absorbing layer;

a reflective layer over the optical stack; and

one or more posts to support the reflective layer, each of the one or more posts including a second light absorbing layer integrated in the post,

wherein the second light absorbing layer is separate from the first light absorbing layer, and

wherein a portion of the second light absorbing layer within a given post extends over a portion of the first light absorbing layer within the optical stack such that the portion of the second light absorbing layer overlaps the portion of the first light absorbing layer.

2. The system of claim 1 wherein:

the first light absorbing layer comprises a first black matrix layer; and

the second light absorbing layer comprises a second black matrix layer.

3. The system of claim 2, wherein:

the first black matrix layer comprises a first absorber layer, a first dielectric layer, and a first reflective layer; and

the second black matrix layer comprises a second absorber layer and a second dielectric layer.

4. The system of claim 3, wherein:

the first absorber layer has substantially a same thickness as the second absorber layer; and

the first dielectric layer has substantially a same thickness as the second dielectric layer.

5. The system of claim 1 as a display system, further comprising:

a display including the system;

a processor that is in electrical communication with the display, the processor being configured to process image data; and

a memory device in electrical communication with the processor.

6. The display system of claim 5, further comprising:

a driver circuit configured to send at least one signal to the display.

7. The display system of claim 6, further comprising:

a controller configured to send at least a portion of the image data to the driver circuit.

8. The display system of claim 5, further comprising:

an image source module configured to send the image data to the processor.

9. The display system of claim 8, wherein the image source module comprises at least one of a receiver, transceiver, and transmitter.

10. The display system of claim 5, further comprising:

an input device configured to receive input data and to communicate the input data to the processor.

11. The system of claim 1, wherein the first light absorbing layer comprises a light absorbing material selected from a group consisting of photo resist and polymer.

12. The system of claim 1, wherein the second light absorbing layer comprises a light absorbing material selected from a group consisting of photo resist and polymer.

13. An electromechanical system comprising:

a means for transmitting light; and

means for modulating light, comprising;

first means for absorbing light coupled to the transmitting means;

a means for conducting electricity, said electricity conducting means comprising a means for partially reflecting light, said electricity conducting means separate from the first light absorbing means;

means for reflecting light, the reflecting means over the first absorbing means; and

means for supporting the reflecting means, said supporting means comprising a second means for absorbing light, wherein the second absorbing means is integrated in the supporting means,

wherein the second absorbing means is separate from the first absorbing means, and

wherein a portion of the second light absorbing means within the supporting means extends over a portion of the first light absorbing means within the optical stack means such that a portion of the second light absorbing means overlaps a portion of the first light absorbing means.

14. The system of claim 13, wherein:

the first absorbing means comprises a first black matrix layer; and

the second absorbing means comprises a second black matrix layer.

15. The system of claim 14, wherein:

the first black matrix layer comprises a first absorber layer, a first dielectric layer, and a first reflective layer; and

the second black matrix layer comprises a second absorber layer and a second dielectric layer.

16. The system of claim 15, wherein:

the first absorber layer has substantially a same thickness as the second absorber layer; and

the first dielectric layer has substantially a same thickness as the second dielectric layer.

17. The system of claim 13, wherein the transmitting means comprises a transparent substrate.

18. The system of claim 13, wherein the first absorbing means comprises an optical stack comprising a first light absorbing layer, the supporting means comprises one or more posts, and the second absorbing means comprises a second light absorbing layer.

19. The system of claim 13, wherein the first absorbing means comprises a light absorbing material selected from a group consisting of photo resist and polymer.

20. The system of claim 13, wherein the second absorbing means comprises a light absorbing material selected from a group consisting of photo resist and polymer.

21. A method for forming an electromechanical system, the method comprising:

providing a transparent substrate;

forming a first light absorbing layer on the transparent substrate;

forming a conducting layer including a partially reflective layer on the transparent substrate, the conducting layer separate from the first light absorbing layer;

forming a reflective layer over the conducting layer; and

forming one or more posts to support the reflective layer, the one or more posts being formed over the transparent substrate and over portions of the conducting layer that do not overlap with the first light absorbing layer,

wherein forming one or more posts includes integrating a second light absorbing layer into the one or more posts, wherein the second light absorbing layer is separate from the first light absorbing layer, and

wherein a portion of the second light absorbing layer extends over a portion of the first light absorbing layer such that a portion of the second light absorbing layer overlaps a portion of the first light absorbing layer.

22. The method of claim 21, wherein:

forming a first light absorbing layer on the transparent substrate comprises forming

a first black matrix layer on the transparent substrate; and

integrating a second light absorbing layer into the one or more posts comprises integrating a second black matrix layer into the one or more posts.

23. An interferometric modulator display device manufactured in accordance with the method of claim 21.

24. A method of modulating light, the method comprising:

providing an electromechanical system comprising;

a transparent substrate; and

a plurality of modulators comprising an optical stack, a reflective layer over the optical stack, and one or more posts supporting the reflective layer over the optical stack, wherein the optical stack comprises;

a first light absorbing layer;

a conducting layer including a partially reflective layer, said conducting layer separate from the partially reflective layer;

and the one or more posts comprises a second light absorbing layer integrated in the one or more posts, wherein the second light absorbing layer is separate from the first light absorbing layer;

transmitting light through the transparent substrate and the optical stack, the light irradiating the reflective layer; and

moving the reflective layer relative to the optical stack.

25. An electromechanical system comprising:

a transparent substrate; and

a plurality of interferometric modulators comprising;

an optical stack coupled to the transparent substrate, the optical stack including a first light absorbing layer;

a reflective layer over the optical stack; and

one or more posts to support the reflective layer, each of the one or more posts including a second light absorbing layer integrated in the post,

wherein the second light absorbing layer is separated from the first light absorbing layer by an air gap, and

wherein a portion of the second light absorbing layer within a given post extends over a portion of the first light absorbing layer within the optical stack such that the portion of the second light absorbing layer overlaps the portion of the first light absorbing layer.