Thin film transistor array panel having an oxide semiconductor including silicon

1. A thin film transistor array panel comprising:

a substrate;

an oxide semiconductor layer disposed on the substrate;

an insulating layer disposed on the oxide semiconductor layer; and

a pixel electrode disposed on the insulating layer,

wherein the oxide semiconductor layer is a double layer consisting of a first layer and a second layer disposed on the first layer, the first layer being between the substrate and the second layer, the first layer comprising an oxide semiconductor, the second layer comprises the same oxide semiconductor as the first layer and further including silicon, and the second layer contacts the insulating layer, wherein the second layer is thinner than the first layer.

2. The thin film transistor array panel of claim 1 , wherein

the second layer comprises the oxide semiconductor including at least one of indium, gallium, zinc, and tin mixed with the silicon.

3. The thin film transistor array panel of claim 2 , wherein

the first layer comprises the oxide semiconductor including at least one of indium, gallium, zinc, and tin.

4. The thin film transistor array panel of claim 3 , wherein

the insulating layer includes a silicon-based oxide or nitride.

5. The thin film transistor array panel of claim 4 , wherein

the first layer is an indium-gallium-zinc oxide semiconductor layer, and the second layer is an indium-gallium-zinc oxide semiconductor layer doped with the silicon.

6. The thin film transistor array panel of claim 1 , further comprising:

a gate insulating layer disposed on the substrate;

a gate electrode disposed on the gate insulating layer; and

source and drain electrodes disposed between the second layer and the insulating layer,

wherein the source and drain electrodes are separated from each other, and the second layer contacts the insulating layer at a separated space between the source and drain electrodes.

7. The thin film transistor array panel of claim 1 , further comprising:

a gate insulating layer disposed on the substrate;

a gate electrode disposed on the gate insulating layer;

source and drain electrodes disposed between the second layer and the insulating layer and separated from each other; and

a passivation layer covering the source and drain electrodes and contacting the insulating layer in a separated space between the source and drain electrodes.

8. The thin film transistor array panel of claim 1 , further comprising:

a gate electrode disposed on the insulating layer;

an interlayer insulating layer disposed on the gate electrode and including a contact hole; and

source and drain electrodes disposed on the interlayer insulating layer and connected to the oxide semiconductor layer through the contact hole.

9. The thin film transistor array panel of claim 1 , further comprising:

a source electrode entirely and directly disposed on the second layer, in at least one cross sectional view; and

a drain electrode entirely and directly disposed on the second layer, in the at least one cross sectional view.

10. A thin film transistor array panel comprising:

a substrate;

an oxide semiconductor layer disposed on the substrate;

an insulating layer disposed on the oxide semiconductor layer; and

a pixel electrode disposed on the insulating layer,

wherein the oxide semiconductor layer is a double layer consisting of a first layer and a second layer disposed on the first layer, the first layer being between the substrate and the second layer,

the first layer comprises an oxide semiconductor including at least one of indium, gallium, zinc, and tin, the second layer comprises the same oxide semiconductor as the first layer doped with a material having a lower standard electrode potential (SEP) than gallium (Ga), and the second layer contacts the insulating layer, wherein the second layer is thinner than the first layer.

11. The thin film transistor array panel of claim 10 , wherein

the material having the lower standard electrode potential (SEP) than the gallium (Ga) is silicon.

12. A manufacturing method of a thin film transistor array panel, comprising:

forming an oxide semiconductor layer being a double layer consisting of first and second layers on a substrate;

forming an insulating layer on the oxide semiconductor layer; and

forming a pixel electrode on the insulating layer,

wherein the second layer is formed on the first layer, the first layer being between the substrate and the second layer, the first layer comprising an oxide semiconductor, the second layer is formed of the same oxide semiconductor as the first layer and further doped with a material having a lower standard electrode potential (SEP) than gallium (Ga), and the second layer contacts the insulating layer, wherein the second layer is thinner than the first layer.

13. The manufacturing method of claim 12 , wherein

the oxide semiconductor layer is formed by a sputtering method, and the first and second layers are formed by using one sputtering target.

14. The manufacturing method of claim 13 , wherein

the sputtering target is formed by combining a plurality of target sheets.

15. The manufacturing method of claim 14 , wherein

the sputtering target includes a first target region and a second target region,

the first target region includes a forming material of the first layer and the second target region includes a forming material of the second layer, and

the second target region is disposed at an outmost side of the sputtering target.

16. The manufacturing method of claim 15 , wherein

the forming of the oxide semiconductor layer includes sequentially moving the substrate to the first target region and the second target region.

17. The manufacturing method of claim 12 , wherein

the second layer comprises the oxide semiconductor including at least one of indium, gallium, zinc, and tin mixed with silicon.

18. The manufacturing method of claim 17 , wherein

the first layer is the oxide semiconductor including at least one of indium, gallium, zinc, and tin.

19. The manufacturing method of claim 18 , wherein

the material having the lower standard electrode potential (SEP) than the gallium (Ga) is silicon.

20. The manufacturing method of claim 19 , wherein

the insulating layer includes a silicon-based oxide or nitride.