Method for fabricating polysilicon liquid crystal display device

1. A method for fabricating a polysilicon liquid crystal display device, comprising:

forming a first amorphous silicon layer on a substrate;

forming a photoresist pattern on the first amorphous silicon layer;

forming a second amorphous silicon layer over the photoresist pattern and the first amorphous silicon layer;

defining a channel region on the first amorphous silicon layer;

crystallizing the first and second silicon layers;

forming an active layer by patterning the crystallized silicon layers;

forming a first insulating layer on the active layer;

forming a gate electrode on the first insulating layer;

forming source and drain electrodes electrically connected to the active layer; and

forming a pixel electrode electrically connected to the drain electrode.

2. The method of claim 1 , wherein the forming the second amorphous silicon layer includes:

adding high density impurity ions to a plasma for depositing the amorphous silicon.

3. The method of claim 2 , wherein the high density impurity ions includes Group III or Group V type ions.

4. The method of claim 1 , wherein the defining the channel region on the first amorphous silicon layer is performed by lifting off the photoresist pattern and a portion of the second amorphous silicon layer on the photoresist pattern.

5. The method of claim 2 , wherein the impurity ions added in the second amorphous silicon layer are activated while crystallizing the first and second amorphous silicon layers.

6. The method of claim 2 , wherein the adding high density impurity ions to the amorphous silicon includes:

introducing the high density impurity ions into a process chamber while the amorphous silicon is deposited.

7. A method for fabricating a liquid crystal display device, comprising:

forming a first amorphous silicon layer on a substrate;

forming an organic layer pattern on the first amorphous silicon layer;

forming a second amorphous silicon having high density impurity ions on the organic layer pattern; and

removing the organic layer pattern and a portion of the second amorphous silicon layer on the organic layer at the same time.

8. The method of claim 7 , wherein removing the organic layer pattern and the second amorphous silicon layer on the organic layer pattern at the same time is performed by a lift-off process.

9. The method of claim 7 , wherein the organic layer pattern includes a photoresist organic layer.

10. The method of claim 7 , further comprising:

crystallizing the first amorphous silicon layer and remaining second amorphous silicon layer.

11. The method of claim 7 , wherein a channel region is defined by removing the organic layer pattern and a portion of the second amorphous silicon layer on the organic layer at the same time.

12. The method of claim 10 , wherein the first and second amorphous silicon layers are activated during crystallization.