Array substrate for liquid crystal display device and manufacturing method thereof

A method of fabricating a liquid crystal display device having an array substrate, comprising:

• forming a gate line on a substrate;
• forming a data line crossing the gate line and defining a pixel area;
• forming a thin film transistor connected to the gate line and the data line, the thin film transistor having a gate electrode connected to the gate line, a source electrode over the gate electrode and connected to the data line, a drain electrode spaced apart from the source electrode, and a semiconductor layer having an active layer over the gate electrode and a first extended portion completely covered with the drain electrode at a boundary between the active layer and the first extended portion, wherein the first extended portion is disposed over the gate electrode;
• and
• forming a pixel electrode in the pixel area, the pixel electrode electrically connected to the drain electrode.

A method of fabricating for a liquid crystal display device having an array substrate, comprising:

• forming a gate line and a gate electrode on a substrate;
• forming a gate insulating layer on the gate line and the gate electrode;
• forming a semiconductor layer on the gate insulating layer, the semiconductor layer having an active layer over the gate electrode and a first extended portion, wherein the first extended portion at a boundary with the active layer is disposed over the gate electrode;
• forming a data line, a source electrode, and a drain electrode on the semiconductor layer, the data line crossing the gate line and defining a pixel area, the source electrode disposed over the gate electrode and connected to the data line, the drain electrode spaced apart from the source electrode and completely covering the first extended portion of the semiconductor layer at a boundary between the first extended portion and the active layer;
• forming a passivation layer on the data line, the source electrode, and the drain electrode;
• and
• forming a pixel electrode in the pixel area on the passivation layer, the pixel electrode connected to the drain electrode.