Touch panel including multilayer touch signal line

1. A touch panel comprising:

a substrate;

touch electrodes disposed on the substrate, the touch electrodes being configured to sense a touch input; and

touch signal lines connected to a corresponding touch electrode of the touch electrodes, each of the touch signal lines comprising a fanout portion and a pad portion, the pad portion being configured to form an electrical connection with a touch controller,

wherein:

each of the fanout portion and the pad portion comprises a first conductor, a second conductor disposed on the first conductor, a third conductor disposed on the second conductor, and a passivation layer disposed on the third conductor; and

a width of the first conductor is wider than a width of the third conductor.

2. The touch panel of claim 1 , wherein:

the third conductor of the pad portion surrounds side surfaces of the second conductor of the pad portion; and

the third conductor of the fanout portion surrounds side surfaces of the second conductor of the fanout portion.

3. The touch panel of claim 2 , wherein:

the touch electrodes and the first conductor are formed of nanowire.

4. The touch panel of claim 3 , wherein:

the second conductor consists of a metal different from materials of the first conductor conductors and the third conductor.

5. The touch panel of claim 4 , wherein:

the third conductor comprises transparent conductive oxide.

6. The touch panel of claim 5 , wherein:

the passivation layer comprises silicon oxide or silicon nitride; and

a portion of the passivation layer disposed on the pad portion comprises an opening exposing a top surface of the third conductor of the pad portion.

7. The touch panel of claim 1 , further comprising:

a fourth conductor between the first conductor and the second conductor.

8. The touch panel of claim 7 , wherein:

the fourth conductor comprises a same material as the third conductor.

9. The touch panel of claim 7 , wherein the touch electrodes comprise:

a first layer formed of nanowirel;

a second layer formed of the same material as the fourth conductor disposed on the first conductor; and

a third layer formed of the same material as the third conductor disposed on the second conductor.

10. The touch panel of claim 1 , wherein:

the width of the third conductor is wider than a width of the second conductor.

11. A method for manufacturing a touch panel, the touch panel comprising touch electrodes and touch signal lines connected to a corresponding touch electrode of the touch electrodes, each of the touch signal lines comprising a fanout portion and a pad portion, the method comprising:

forming a first conductive layer on a substrate;

forming an etch stopping layer on the first conductive layer;

forming and patterning a second conductive layer on the etch stopping layer to form a second conductor of the fanout portion and a second conductor of the pad portion;

forming, after patterning the second conductive layer, a third conductive layer on the second conductor of the fanout portion and the second conductor of the pad portion,

patterning the third conductive layer to form a third conductor of the fanout portion on the second conductor of the fanout portion and a third conductor of the pad portion on the second conductor of the pad portion;

patterning, after patterning the third conductive layer, the first conductive layer to form a first conductor of the fanout portion and a first conductor of the pad portion; and

forming a passivation layer on the third conductors and the touch electrodes.

12. The method of claim 11 , wherein:

the second conductor of the pad portion is formed to have a width narrower than a width of the third conductor of the pad portion, and the third conductor of the pad portion is formed to surround side surfaces of the second conductor of the pad portion; and

the second conductor of the fanout portion is formed to have a width narrower than a width of the third conductor of the fanout portion, and the third conductor of the fanout portion is formed to surround side surfaces of the second conductor of the fanout portion.

13. The method of claim 11 , further comprising:

patterning the etch stopping layer to form a fourth conductor of the fanout portion and a fourth conductor of the pad portion, the fourth conductor of the fanout portion being disposed between the first conductive layer and the second conductor of the fanout portion, the fourth conductor of the pad portion being disposed between the first conductive layer and the second conductor of the pad portion,

wherein the patterning of the etch stopping layer is performed simultaneously with the patterning of the third conductive layer.

14. The method of claim 13 , wherein:

the third conductor of the pad portion is formed to be in contact with the fourth conductor of the pad portion while surrounding side surfaces of the second conductor of the pad portion; and

the third conductor of the fanout portion is formed to be in contact with the fourth conductor of the fanout portion while surrounding side surfaces of the second conductor of the fanout portion.

15. The method of claim 11 , wherein:

the first conductive layer comprises nanowire.

16. The method of claim 15 , wherein:

the second conductive layer consists of a metal different from materials of the first conductor of the fanout portion, the first conductor of the pad portion, the third conductor of the fanout portion, and the third conductor of the pad portion.

17. The method of claim 16 , wherein:

the third conductive layer comprises transparent conductive oxide.

18. The method of claim 17 , wherein:

the passivation layer comprises silicon oxide or silicon nitride; and

a portion of the passivation layer disposed on the pad portion is formed to comprise an opening exposing a top surface of the third conductor of the pad portion.

19. A touch panel comprising:

a substrate;

a touch electrode disposed on the substrate, the touch electrode being configured to sense a touch input;

a touch signal line connected to the touch electrode, the touch signal line comprising a fanout portion and a pad portion, the pad portion being configured to form an electrical connection with to a touch controller; and

a passivation layer disposed on the touch signal line and the touch electrode,

wherein the fanout portion comprises:

a first conductor extending from the touch electrode;

a second conductor disposed on the first conductor of the fanout portion;

a third conductor disposed on the second conductor of the fanout portion; and

a fourth conductor disposed between the first conductor of the fanout portion and the second conductor of the fanout portion, and

wherein the pad portion comprises:

a first conductor extending from the first conductor of the fanout portion;

a second conductor disposed on the first conductor of the pad portion, the second conductor of the pad portion extending from the second conductor of the fanout portion; and

a third conductor disposed on the second conductor of the pad portion; and

a fourth conductor disposed between the first conductor of the pad portion and the second conductor of the pad portion, the fourth conductor of the pad portion extending from the fourth conductor of the fanout portion.