The active layer may include a source region including the first protrusion and implanted with the ions, a drain region including the second protrusion and implanted with the ions, and a channel region formed between the source region and the drain region and not implanted with the ions.

The channel region may overlap the gate electrode.

Forming the source contact hole and the drain contact hole may include removing the first protrusion and the second protrusion of the polysilicon pattern.

Forming the source contact hole and the drain contact hole may further include forming a first recess overlapping the source contact hole and a second recess overlapping the drain contact hole in the active layer.

In the method of manufacturing the display device according to the inventive concepts, the active layer in which the regions respectively overlapping the source contact hole and the drain contact hole are relatively thick may be formed, or the active layer including the protrusions respectively overlapping the source contact hole and the drain contact hole may be formed, so that the active layer may not be damaged in the process of forming the source contact hole and the drain contact hole. Accordingly, characteristics of the thin film transistor of the display device may be improved.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.