Display device and manufacturing method thereof

1. A display device, comprising:

an insulation substrate;

a source electrode and a drain electrode disposed on the insulation substrate, and distanced from each other and including a channel area interposed therebetween;

a wall exposing portions of the source electrode and the drain electrode, and defining an opening area surrounding the channel area; and

an organic semiconductor layer covering the channel area, and comprising a first sub layer and a second sub layer, the first sub layer and the second sub layer having different grain sizes

wherein the source electrode and the drain electrode directly contact the first sub layer and the second sub layer.

2. The display device according to claim 1 , wherein the second sub layer is disposed on the first sub layer, and the grain size of the second sub layer is larger than that of the first sub layer.

3. The display device according to claim 2 , wherein the first sub layer is disposed in a portion of the opening area, and the second sub layer is disposed in an entire portion of the opening area.

4. The display device according to claim 1 , wherein the opening area comprises a recess.

5. The display device according to claim 4 , wherein a portion of the first sub layer is disposed in the recess.

6. The display device according to claim 4 , wherein the opening area comprises a protruding area extending outwardly towards the wall, and a portion of the recess is formed on the protruding area.

7. The display device according to claim 4 , wherein the source electrode surrounds the drain electrode, and the channel area has a C-shape.

8. The display device according to claim 7 , wherein a portion of the recess surrounds the source electrode.

9. The display device according to claim 7 , wherein the drain electrode comprises a closed loop part and a portion of the recess is formed inside the closed loop part.

10. The display device according to claim 4 , further comprising a metal layer positioned under the source electrode and the drain electrode,

wherein the metal layer does not overlap with the recess.

11. The display device according to claim 10 , further comprising an insulation layer covering the metal layer and positioned under the source electrode and the drain electrode,

wherein the recess is disposed on the insulation layer.

12. The display device according to claim 4 , wherein the source electrode and the drain electrode comprise ITO (indium tin oxide) or IZO (indium zinc oxide).

13. A display device, comprising:

an insulation substrate;

an insulation layer disposed on the insulation substrate and comprising a recess;

a source electrode and a drain electrode disposed on the insulation substrate, positioned adjacent to the recess, and distanced from each other including a channel area interposed between the source electrode and the drain electrode;

an organic layer, a portion of the organic layer disposed in the recess; and

an organic semiconductor layer disposed on the organic layer covering the channel area,

wherein the source electrode and the drain electrode directly contact the organic layer and the organic semiconductor layer having different grain sizes from each other.

14. The display device according to claim 13 , wherein the organic layer comprises an organic semiconductor material.

15. The display device according to claim 14 , wherein a grain size of the organic semiconductor layer is larger than a grain size of the organic layer.

16. The display device according to claim 15 , further comprising a metal layer positioned under the insulation layer,

wherein the metal layer overlaps the source electrode, the drain electrode and the channel area.