Antistatic device of display device and method of manufacturing the same

1. An antistatic device for a display device, the antistatic device comprising:

a first switching thin film transistor (TFT) in which an active layer is formed of oxide;

a second switching TFT in which an active layer is formed of oxide; and

an equalizer TFT in which an active layer is formed of amorphous silicon.

2. The antistatic device of claim 1 , wherein a thickness of a gate insulating layer of each of the first and second switching TFTs differs from a thickness of a gate insulating layer of the equalizer TFT.

3. The antistatic device of claim 1 , wherein a switching speed of each of the first and second switching TFTs differs from a switching speed of the equalizer TFT.

4. The antistatic device of claim 1 , wherein the equalizer TFT comprises:

a light shield formed of amorphous silicon, and used as an active layer;

a first gate insulating layer formed on the light shield;

a source connected to one side of the light shield; and

a drain connected to the another side of the light shield.

5. The antistatic device of claim 1 , wherein each of the first and second switching TFTs comprises:

an active layer formed of oxide;

a second gate insulating layer formed on the active layer;

a source connected to one side of the active layer; and

a drain connected to another side of the active layer.

6. The antistatic device of claim 1 , wherein,

a gate and a source of each of the first and second switching TFTs are connected to each other, and each of the first and second switching TFTs operates as a diode,

drains of the first and second switching TFTs are connected to a gate of the equalizer TFT,

a source of the equalizer TFT is connected to the source of the first switching TFT, and

a drain of the equalizer TFT is connected to the source of the second switching TFT.

7. A display device comprising:

a display panel configured to display images and including a plurality of gate lines, a plurality of data lines and a plurality of pixels; and

the antistatic device of claim 1 , connected to an input end of at least one of the data lines and to an input end of at least one of the gate lines.

8. A method of manufacturing an antistatic device including a plurality of switching thin film transistors (TFTs) and an equalizer TFT, the method comprising:

forming a light shield with amorphous silicon, on a buffer layer which is formed on a substrate;

forming a first gate insulating layer to cover the light shield;

forming an active layer with oxide, in a switching TFT area on the first gate insulating layer;

forming a second gate insulating layer to cover the active layer;

forming a gate of each of the plurality of switching TFTs on the second gate insulating layer, and forming a gate of the equalizer TFT in an equalizer TFT area on the first gate insulating layer;

forming an interlayer dielectric to cover the gate of each of the plurality of switching TFTs and the gate of the equalizer TFT;

etching a portion of the interlayer dielectric to form a plurality of contact holes which expose a top of the active layer and a top of the light shield;

forming a source and a drain of each of the plurality of switching TFTs to be connected to the active layer, and forming a source and a drain of the equalizer TFT to be connected to the light shield; and

forming a passivation layer to cover the plurality of switching TFTs and the equalizer TFT.

9. The method of claim 8 , wherein the light shield is formed as an active layer of the equalizer TFT.

10. The method of claim 8 , wherein a thickness of the first gate insulating layer differs from a thickness of the second gate insulating layer.

11. The method of claim 8 , wherein the second gate insulating layer of each of the plurality of switching TFTs is thinner in thickness than a gate insulating layer of a TFT which is formed in an active area of a display panel.