Display device and manufacturing method thereof

• US 8,749,061 B2
• Filed: 05/23/2013
• Issued: 06/10/2014
• Est. Priority Date: 09/20/2002
• Status: Expired due to Term

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamazaki, Shunpei, Osame, Mitsuaki
• Primary Examiner(s): Blum, David S
• Application Number:
  US13/900,903
• Publication Number:
  US 20130256892A1
• Time in Patent Office: 383 Days
• Field of Search: 257/66, 257/751, 257/784, 257/E33.001
• US Class Current: 257/751
• CPC Class Codes: G02F 1/133345 Insulating layers G02F1/1335, G02F1/1337, G02F1/135, G02F1/136 take precedence
• CPC Class Codes: G02F 1/136286 Wiring, e.g. gate line, drain line
• CPC Class Codes: G02F 1/13629 Multilayer wirings
• CPC Class Codes: G02F 1/136295 Materials; Compositions; Manufacture processes
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: G02F 2201/123 pixel
• CPC Class Codes: H01L 23/50 for integrated circuit devices, e.g. power bus, number of leadsH01L23/482 - H01L23/498 take precedence
• CPC Class Codes: H01L 23/53238 Additional layers associated with copper layers, e.g. adhesion, barrier, cladding layers
• CPC Class Codes: H01L 27/124 with a particular composition, shape or layout of the wiring layers specially adapted to the circuit arrangement, e.g. scanning lines in LCD pixel circuits wiring structures per se H01L23/52
• CPC Class Codes: H01L 27/1248 with a particular composition or shape of the interlayer dielectric specially adapted to the circuit arrangement
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H05K 1/09 Use of materials for the conductive, e.g. metallic pattern
• CPC Class Codes: H05K 5/0017 with operator interface units
• CPC Class Codes: H10K 59/122 Pixel-defining structures or layers, e.g. banks
• CPC Class Codes: H10K 59/124 Insulating layers formed between TFT elements and OLED elements
• CPC Class Codes: H10K 59/1315 comprising structures specially adapted for lowering the resistance

Abstract

It is an object of the present invention to prevent an influence of voltage drop due to wiring resistance, trouble in writing of a signal into a pixel, and trouble in gray scales, and provide a display device with higher definition, represented by an EL display device and a liquid crystal display device.

In the present invention, a wiring including Cu is provided as an electrode or a wiring used for the display device represented by the EL display device and the liquid crystal display device. Besides, sputtering is performed with a mask to form the wiring including Cu. With such structure, it is possible to reduce the voltage drop and a deadened signal.

Claims

1. A display device comprising a protective circuit, the protective circuit comprising:

a first wiring;

an insulating film over the first wiring;

a second wiring over the insulating film; and

a semiconductor film under the insulating film,

wherein the first wiring is electrically connected to the semiconductor film through a first opening of the insulating film,

wherein the second wiring is electrically connected to the semiconductor film through a second opening of the insulating film,

wherein the first wiring overlaps with the second wiring,

wherein the second wiring comprises a first layer comprising titanium and a second layer comprising copper,

wherein the second layer is over and in contact with the first layer, and

wherein a width of the second layer is narrower than a width of the first layer.

2. The display device according to claim 1, wherein the first layer comprises a first conductive layer comprising titanium and a second conductive layer comprising titanium nitride.

3. The display device according to claim 2, wherein the second conductive layer is a conductive barrier film.

4. The display device according to claim 1, wherein the second wiring is a taken-around wiring which is electrically connected to a FPC.

5. The display device according to claim 1, wherein the semiconductor film comprises silicon.

6. The display device according to claim 1, wherein the semiconductor film has a zigzag shape.

7. A display device comprising a protective circuit, the protective circuit comprising:

a first wiring;

an insulating film over the first wiring;

a second wiring and a third wiring over the insulating film; and

a semiconductor film under the insulating film,

wherein the first wiring is in contact with the third wiring through a first opening of the insulating film,

wherein the second wiring is electrically connected to the semiconductor film through a second opening of the insulating film,

wherein the third wiring is in contact with the semiconductor film through a third opening of the insulating film,

wherein the first wiring overlaps with the second wiring,

wherein the second wiring comprises a first layer comprising titanium and a second layer comprising copper,

wherein the second layer is over and in contact with the first layer, and

wherein a width of the second layer is narrower than a width of the first layer.

8. The display device according to claim 7, wherein the first layer comprises a first conductive layer comprising titanium and a second conductive layer comprising titanium nitride.

9. The display device according to claim 8, wherein the second conductive layer is a conductive barrier film.

10. The display device according to claim 7, wherein the second wiring is a taken-around wiring which is electrically connected to a FPC.

11. The display device according to claim 7, wherein the semiconductor film comprises silicon.

12. The display device according to claim 7, wherein the semiconductor film has a zigzag shape.

13. A display device comprising:

a pixel comprising a light emitting element; and

a protective circuit electrically connected to the pixel through a first wiring, the protective circuit comprising;

an insulating film over the first wiring;

a second wiring over the insulating film; and

a semiconductor film under the insulating film,

wherein the first wiring is electrically connected to the semiconductor film through a first opening of the insulating film,

wherein the second wiring is electrically connected to the semiconductor film through a second opening of the insulating film,

wherein the first wiring overlaps with the second wiring,

wherein the second wiring comprises a first layer comprising titanium and a second layer comprising copper,

wherein the second layer is over and in contact with the first layer, and

wherein a width of the second layer is narrower than a width of the first layer.

14. The display device according to claim 13, wherein the first layer comprises a first conductive layer comprising titanium and a second conductive layer comprising titanium nitride.

15. The display device according to claim 14, wherein the second conductive layer is a conductive barrier film.

16. The display device according to claim 13, wherein the second wiring is a taken-around wiring which is electrically connected to a FPC.

17. The display device according to claim 13, wherein the semiconductor film comprises silicon.

18. The display device according to claim 13, wherein the semiconductor film has a zigzag shape.

19. A display device comprising:

a plastic substrate;

a pixel comprising a light emitting element over the plastic substrate; and

a protective circuit electrically connected to the pixel through a first wiring, the protective circuit comprising;

an insulating film over the first wiring;

a second wiring over the insulating film; and

a semiconductor film under the insulating film,

wherein the first wiring is electrically connected to the semiconductor film through a first opening of the insulating film,

wherein the second wiring is electrically connected to the semiconductor film through a second opening of the insulating film,

wherein the first wiring overlaps with the second wiring,

wherein the second wiring comprises a first layer comprising titanium and a second layer comprising copper,

wherein the second layer is over and in contact with the first layer, and

wherein a width of the second layer is narrower than a width of the first layer.

20. The display device according to claim 19, wherein the first layer comprises a first conductive layer comprising titanium and a second conductive layer comprising titanium nitride.

21. The display device according to claim 20, wherein the second conductive layer is a conductive barrier film.

22. The display device according to claim 19, wherein the second wiring is a taken-around wiring which is electrically connected to a FPC.

23. The display device according to claim 19, wherein the semiconductor film comprises silicon.

24. The display device according to claim 19, wherein the semiconductor film has a zigzag shape.