Organic light-emitting display

1. An organic light-emitting display comprising:

a substrate;

a thin film transistor formed on the substrate, and comprising i) a gate electrode, ii) an active layer electrically insulated from the gate electrode, wherein the active layer has top and bottom surfaces opposing each other and a side surface interposed between the top and bottom surfaces and iii) source and drain electrodes that are electrically connected to the top surface of the active layer;

a first electrode electrically connected to the thin film transistor;

an intermediate layer formed on the first electrode and comprising an organic emission layer; and

a second electrode formed on the intermediate layer,

wherein the source electrode or the drain electrode has an optical blocking portion extending in the direction of substrate thickness, and wherein the optical blocking portion is closer to the substrate than the bottom surface of the active layer.

2. The organic light-emitting display of claim 1 , wherein the source electrode or the drain electrode is electrically connected to the first electrode,

and wherein the source or drain electrode that is connected to the first electrode comprises the optical blocking portion.

3. The organic light-emitting display of claim 1 , wherein the active layer is formed at least partially of an oxide semiconductor material.

4. The organic light-emitting display of claim 1 , wherein the gate electrode is formed on the substrate,

wherein the active layer is formed over the gate electrode, and

wherein the optical blocking portion includes a region that overlaps with at least part of the gate electrode in a direction substantially perpendicular to the substrate thickness.

5. The organic light-emitting display of claim 4 , wherein the optical blocking portion contacts the substrate.

6. The organic light-emitting display of claim 4 , further comprising a buffer layer formed between the substrate and the thin film transistor,

wherein the optical blocking portion contacts the buffer layer.

7. The organic light-emitting display of claim 4 , further comprising a passivation layer disposed between the thin film transistor and the first electrode, the passivation layer including a via-hole,

wherein the source electrode or the drain electrode is connected to the first electrode by way of the via-hole, and

wherein the optical blocking portion includes a region that overlaps with at least part of the via-hole in the thickness direction of the substrate.

8. The organic light-emitting display of claim 1 , wherein the gate electrode is formed on the substrate,

wherein the active layer is formed on the gate electrode,

wherein the organic light-emitting display further comprising a conductive unit formed on the substrate to be disposed apart from the gate electrode, and

wherein the optical blocking portion and the conductive unit are connected to each other.

9. The organic light-emitting display of claim 8 , wherein the conductive unit and the gate electrode are formed of the same material.

10. The organic light-emitting display of claim 8 , further comprising a passivation layer disposed between the thin film transistor and the first electrode, the passivation layer including a via-hole,

wherein the source electrode or the drain electrode is electrically connected to the first electrode via the via-hole, and

wherein the optical blocking portion includes a region that overlaps with at least part of the via-hole in the thickness direction of the substrate.

11. The organic light-emitting display of claim 1 , wherein the gate electrode and the first electrode are formed on the substrate to be disposed apart from each other,

wherein the active layer is formed on the gate electrode, and

wherein the optical blocking portion includes a region that overlaps with at least part of the gate electrode in a direction substantially perpendicular to the thickness direction of the substrate.

12. The organic light-emitting display of claim 11 , wherein the optical blocking portion contacts a side surface of the first electrode.

13. The organic light-emitting display of claim 11 , wherein the optical blocking portion contacts a side surface of the first electrode facing the gate electrode.

14. The organic light-emitting display of claim 11 , wherein the optical blocking portion at least partially covers a side surface of the first electrode, which contacts the substrate.

15. The organic light-emitting display of claim 11 , further comprising a buffer layer disposed between the substrate and the first electrode,

wherein the optical blocking portion at least partially covers a side surface of the first electrode that contacts the buffer layer.

16. An organic light-emitting display comprising:

a thin film transistor (TFT) formed on a substrate, wherein the TFT comprises i) a gate electrode, ii) an active layer electrically insulated from the gate electrode wherein the active layer has top and bottom surfaces opposing each other and a side surface interposed between the top and bottom surfaces, and iii) source and drain electrodes electrically connected to the top surface of the active layer;

a first electrode electrically connected to the TFT;

an organic light emission layer formed on the first electrode and configured to emit light; and

a second electrode formed on the organic light emission layer,

wherein a portion of at least one of the source electrode and the drain electrode extends in the direction of substrate thickness and is configured to substantially block the emitted light from entering the active layer of the TFT, and wherein the portion is closer to the substrate than the bottom surface of the active layer.

17. The organic light-emitting display of claim 16 , wherein only one of the source and drain electrodes includes the portion, and wherein the electrode having the portion is formed to be closer to the organic light emitting layer than the other electrode.

18. The organic light-emitting display of claim 16 , further comprising a gate insulating layer formed between the gate electrode and active layer, wherein the portion at least partially penetrates the gate insulating layer.

19. The organic light-emitting display of claim 18 , wherein the portion substantially completely penetrates the gate insulating layer.

20. The organic light-emitting display of claim 19 , wherein the portion contacts the substrate or a conductive unit formed between the portion and substrate.