DISPLAY DEVICE

• US 20140240617A1
• Filed: 02/20/2014
• Published: 08/28/2014
• Est. Priority Date: 02/22/2013
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: FUKUTOME, Takahiro, TANABE, Toru
• Granted Patent: US 9,417,475 B2
• Time in Patent Office: Days
• US Class Current: 349/12
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/136209 Light shielding layers, e.g. black matrix, incorporated in the active matrix substrate, e.g. structurally associated with the switching element
• CPC Class Codes: G02F 1/136222 Colour filters incorporated in the active matrix substrate
• CPC Class Codes: G06F 2203/04103 Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes

Abstract

A display device having a novel structure that can improve reliability is provided. It lowers reliability to form a structure by using a photomask, such as a color filter on a rear side of a substrate. With this display device, a transistor and the color filter is provided over a first substrate, a touch sensor is provided on a first surface of a second substrate, and the structure is not provided on a second surface of the second substrate. Consequently, the display device with the touch sensor can perform high reliability.

Claims

1. A display device comprising:

a transistor over a first substrate;

a color filter over the first substrate;

a pixel electrode over the transistor and the color filter, the pixel electrode being electrically connected to a terminal of the transistor;

a second substrate over the pixel electrode; and

a touch sensor over the second substrate.

2. The display device according to claim 1,

wherein a channel formation region of the transistor comprises an oxide semiconductor.

3. The display device according to claim 1,

wherein the color filter includes a black matrix.

4. A display device comprising:

a transistor over a first substrate;

a color filter over the first substrate;

a pixel electrode over the transistor and the color filter, the pixel electrode being electrically connected to a terminal of the transistor;

a liquid crystal layer over the pixel electrode;

an alignment film over the liquid crystal layer;

a second substrate over the alignment film; and

a touch sensor over the second substrate.

5. The display device according to claim 4,

wherein a channel formation region of the transistor comprises an oxide semiconductor.

6. The display device according to claim 4,

wherein the color filter includes a black matrix.

7. A display device comprising:

a transistor over a first substrate;

a color filter over the first substrate;

a pixel electrode and a common electrode over the transistor and the color filter, the pixel electrode being electrically connected to a terminal of the transistor;

a liquid crystal layer over the pixel electrode and the common electrode;

an alignment film over the liquid crystal layer;

a second substrate over the alignment film; and

a touch sensor over the second substrate.

8. The display device according to claim 7,

wherein a channel formation region of the transistor comprises an oxide semiconductor.

9. The display device according to claim 7,

wherein the color filter includes a black matrix.

10. A display device comprising:

a transistor over a first substrate;

a color filter over the first substrate;

a pixel electrode over the transistor and the color filter, the pixel electrode being electrically connected to a terminal of the transistor;

a second substrate over the pixel electrode;

a first electrode, a second electrode, and a third electrode over the second substrate;

an insulating layer over the first electrode, the second electrode, and the third electrode; and

a fourth electrode over the insulating layer,

wherein the first electrode is electrically connected to the second electrode through the fourth electrode, and

wherein the third electrode is electrically isolated from the first electrode, the second electrode, and the fourth electrode.

11. The display device according to claim 10,

wherein a channel formation region of the transistor comprises an oxide semiconductor.

12. The display device according to claim 10,

wherein the color filter includes a black matrix.

13. A display device comprising:

a transistor over a first substrate;

a color filter over the first substrate;

a pixel electrode over the transistor and the color filter, the pixel electrode being electrically connected to a terminal of the transistor;

a liquid crystal layer over the pixel electrode;

an alignment film over the liquid crystal layer;

a second substrate over the alignment film;

a first electrode, a second electrode, and a third electrode over the second substrate;

an insulating layer over the first electrode, the second electrode, and the third electrode; and

a fourth electrode over the insulating layer,

wherein the first electrode is electrically connected to the second electrode through the fourth electrode, and

wherein the third electrode is electrically isolated from the first electrode, the second electrode, and the fourth electrode.

14. The display device according to claim 13,

wherein a channel formation region of the transistor comprises an oxide semiconductor.

15. The display device according to claim 13,

wherein the color filter includes a black matrix.

16. A display device comprising:

a transistor over a first substrate;

a color filter over the first substrate;

a pixel electrode and a common electrode over the transistor and the color filter, the pixel electrode being electrically connected to a terminal of the transistor;

a liquid crystal layer over the pixel electrode and the common electrode;

an alignment film over the liquid crystal layer;

a second substrate over the alignment film;

a first electrode, a second electrode, and a third electrode over the second substrate;

an insulating layer over the first electrode, the second electrode, and the third electrode; and

a fourth electrode over the insulating layer,

wherein the first electrode is electrically connected to the second electrode through the fourth electrode, and

wherein the third electrode is electrically isolated from the first electrode, the second electrode, and the fourth electrode.

17. The display device according to claim 16,

wherein a channel formation region of the transistor comprises an oxide semiconductor.

18. The display device according to claim 16,

wherein the color filter includes a black matrix.

19. A method for manufacturing a display device comprising the steps of:

forming a transistor over a first substrate;

forming a color filter over the first substrate;

forming a pixel electrode over the transistor and the color filter;

forming a touch sensor on a first surface of a second substrate;

forming an alignment film on a second surface of the second substrate; and

attaching the second substrate to the first substrate with a liquid crystal layer interposed between the pixel electrode and the alignment film.

20. The method for manufacturing the display device according to claim 19,

wherein a channel formation region of the transistor comprises an oxide semiconductor.

21. The method for manufacturing the display device according to claim 19,

wherein the color filter includes a black matrix.

22. A method for manufacturing a display device comprising the steps of:

forming a transistor over a first substrate;

forming a color filter over the first substrate;

forming a pixel electrode over the transistor and the color filter;

forming a first electrode, a second electrode, and a third electrode on a first surface of a second substrate;

forming an insulating layer over the first electrode, the second electrode, and the third electrode;

forming a fourth electrode over the insulating layer;

forming an alignment film on a second surface of the second substrate; and

attaching the second substrate to the first substrate with a liquid crystal layer interposed between the pixel electrode and the alignment film,

wherein the first electrode is electrically connected to the second electrode through the fourth electrode, and

wherein the third electrode is electrically isolated from the first electrode, the second electrode, and the fourth electrode.

23. The method for manufacturing the display device according to claim 22,

wherein a channel formation region of the transistor comprises an oxide semiconductor.

24. The method for manufacturing the display device according to claim 22,

wherein the color filter includes a black matrix.

25. A method for manufacturing a display device comprising the steps of:

forming a transistor over a first substrate;

forming a color filter over the first substrate;

forming a pixel electrode and a common electrode over the transistor and the color filter;

forming a first electrode, a second electrode, and a third electrode on a first surface of a second substrate;

forming an insulating layer over the first electrode, the second electrode, and the third electrode;

forming a fourth electrode over the insulating layer;

forming an alignment film on a second surface of the second substrate; and

attaching the second substrate to the first substrate with a liquid crystal layer interposed between the pixel electrode and the alignment film,

wherein the first electrode is electrically connected to the second electrode through the fourth electrode, and

wherein the third electrode is electrically isolated from the first electrode, the second electrode, and the fourth electrode.

26. The method for manufacturing the display device according to claim 25,

wherein a channel formation region of the transistor comprises an oxide semiconductor.

27. The method for manufacturing the display device according to claim 25,

wherein the color filter includes a black matrix.