Thin film transistor, method of fabricating the same, organic light emitting diode display device including the same and method of fabricating the same

An organic light emitting diode (OLED) display device, comprising:

• a substrate;
• a semiconductor layer disposed on the substrate, including a channel region and source and drain regions, and crystallized using a metal catalyst;
• a gate electrode disposed to correspond to the channel region of the semiconductor layer;
• a gate insulating layer disposed between the gate electrode and the semiconductor layer to insulate the semiconductor layer from the gate electrode;
• source and drain electrodes electrically connected to the source and drain regions of the semiconductor layer, respectively;
• a first electrode electrically connected to one of the source and drain electrodes;
• an organic layer including a light emitting layer disposed on the first electrode;
• and
• a second electrode disposed on the organic layer,
• wherein the metal catalyst is present in the channel region of the semiconductor layer at a concentration exceeding 0 and not exceeding 6.5×E17 atoms per cm3 within 150 Å in a vertical direction,
• wherein the vertical direction starts from a surface of the semiconductor layer that is on an opposite side of the substrate and extends towards the substrate, and
• wherein the metal catalyst is present in the channel region at a concentration exceeding 6.5×E17 atoms per cm3, at a depth exceeding 150 Å in the vertical direction.