Display panel and method of fabricating thin film transistor

1. A display panel, wherein the display panel comprises a thin film transistor layer, the thin film transistor layer comprising a plurality of driving thin film transistors and a plurality of data writing thin film transistors;

wherein each of the data writing thin film transistors comprises:

a substrate;

a light shielding metal layer, the light shielding metal layer is located on the substrate;

a buffer layer, the buffer layer covering the light shielding metal layer;

an active region, the active region is located on the buffer layer, the active region comprises a channel region and a source region and a drain region located on both sides of the channel;

a gate dielectric layer, the gate dielectric layer covering the channel region;

a gate metal layer, the gate metal layer covering the gate dielectric layer; and

each of the data writing thin film transistors further comprises a first via hole penetrating the gate dielectric layer and the buffer layer, and the gate metal layer is electrically connected to the light shielding metal layer through the first via hole;

an interlayer dielectric layer covering the gate metal layer and the active region;

a second via hole, the second via hole is located on the interlayer dielectric layer and exposing the source region and the drain region;

a source/drain metal layer, the source/drain metal layer located on the interlayer dielectric layer and electrically connected to the source region and the drain region through the second via hole;

wherein an area of the light shielding metal layer is larger than an area of the active region, and a projection of the light-shielding metal layer on the substrate completely covers a projection of the active region on the substrate.

2. The display panel according to claim 1 , wherein the first via hole is located on an extension line of the channel region in a channel width direction.

3. The display panel according to claim 2 , wherein a length of the gate metal layer is greater than a length of the channel region, and the gate metal layer extends toward the first via hole and covers the first via hole.

4. The display panel according to claim 3 , wherein the area of the light shielding metal layer is larger than an area of the gate metal layer, and the projection of the light-shielding metal layer on the substrate completely covers a projection of the gate metal layer on the substrate.

5. The display panel according to claim 1 , wherein the projection of the light-shielding metal layer on the substrate completely covers the projection of the active region on the substrate and a projection of the first via hole on the substrate.

6. A display panel, wherein the display panel comprises a thin film transistor layer, the thin film transistor layer comprising a plurality of driving thin film transistors and a plurality of data writing thin film transistors;

wherein each of the data writing thin film transistors comprises:

a substrate;

a light shielding metal layer, the light shielding metal layer is located on the substrate;

a buffer layer, the buffer layer covering the light shielding metal layer;

an active region, the active region is located on the buffer layer, the active region comprises a channel region and a source region and a drain region located on both sides of the channel;

a gate dielectric layer, the gate dielectric layer covering the channel region;

a gate metal layer, the gate metal layer covering the gate dielectric layer; and

each of the data writing thin film transistors further comprises a first via hole penetrating the gate dielectric layer and the buffer layer, and the gate metal layer is electrically connected to the light shielding metal layer through the first via hole;

wherein an area of the light shielding metal layer is larger than an area of the active region, and a projection of the light-shielding metal layer on the substrate completely covers a projection of the active region on the substrate.

7. The display panel according to claim 6 , wherein the first via hole is located on an extension line of the channel region in a channel width direction.

8. The display panel according to claim 7 , wherein a length of the gate metal layer is greater than a length of the channel region, and the gate metal layer extends toward the first via hole and covers the first via hole.

9. The display panel according to claim 8 , wherein the area of the light shielding metal layer is larger than an area of the gate metal layer, and the projection of the light-shielding metal layer on the substrate completely covers a projection of the gate metal layer on the substrate.

10. The display panel according to claim 6 , wherein the projection of the light-shielding metal layer on the substrate completely covers the projection of the active region on the substrate and a projection of the first via hole on the substrate.

11. The display panel according to claim 6 , wherein each of the data writing thin film transistors further comprises:

an interlayer dielectric layer covering the gate metal layer and the active region;

a second via hole, the second via hole is located on the interlayer dielectric layer and exposing the source region and the drain region;

a source/drain metal layer, the source/drain metal layer located on the interlayer dielectric layer and electrically connected to the source region and the drain region through the second via hole.

12. A method of fabricating a thin film transistor, wherein the method comprises:

providing a substrate;

forming a light shielding metal layer, the light shielding metal layer being located on the substrate;

forming a buffer layer, the buffer layer covering the light shielding metal layer;

forming an active region on the buffer layer, the active region comprising a channel region and a source region and a drain region on both sides of the channel region;

forming a gate dielectric layer, the gate dielectric layer covering the channel region;

forming a first via hole, the first via hole penetrating the gate dielectric layer and the buffer layer;

forming a gate metal layer covering the gate dielectric layer, and the gate metal layer is electrically connected to the light shielding metal layer through the first via hole;

wherein an area of the light shielding metal layer is larger than an area of the active region, and a projection of the light-shielding metal layer on the substrate completely covers a projection of the active region on the substrate.

13. The method of fabricating a thin film transistor according to claim 12 , wherein the first via hole is located on an extension line of the channel region along a channel width direction;

wherein a length of the gate metal layer is greater than a length of the channel region, and the gate metal layer extends toward the first via hole and covers the first via hole.

14. The method of fabricating a thin film transistor according to claim 12 , wherein the method further comprises:

forming an interlayer dielectric layer covering the gate metal layer and the active region;

forming a second via hole on the interlayer dielectric layer to expose the source region and the drain region;

forming a source/drain metal layer on the interlayer dielectric layer and electrically connecting the source region and drain region through the second via hole.