A manufacturing method of a thin film transistor, comprising:
- stacking a buffer layer on a substrate;
- forming a semiconductor layer including a channel region, an input region, and an output region on the buffer layer;
- forming a control electrode overlapping the channel region of the semiconductor layer;
- and
- forming an input electrode connected to the input region and an output electrode connected to the output region,
- wherein the forming of the semiconductor layer includes
- stacking an amorphous silicon layer on the buffer layer, and
- applying the blue laser on the amorphous silicon layer to form a polysilicon layer, and
- wherein an angle between grain boundaries of the polysilicon layer and a longitudinal direction of the channel region is within 30 degrees.