Thin film transistor substrate of horizontal electric field type liquid crystal display device and fabricating method thereof

A thin film transistor substrate of horizontal electric field type, comprising:

• a gate line and a first common line formed from a first conductive layer on a substrate to be in parallel to each other;
• a data line crossing the gate line and the first common line with a gate insulating film therebetween to define a pixel area, said data line being formed from a second conductive layer;
• a second common line formed from said second conductive layer and crossing the first common line having the gate insulating film therebetween;
• a thin film transistor connected to the gate line and the data line;
• a common electrode formed from said second conductive layer and extending from the second common line in said pixel area;
• a pixel electrode formed from said second conductive layer that is parallel to the common electrode and the second common line, the pixel electrode being connected to the thin film transistor;
• a protective film for covering the thin film transistor;
• a gate pad having a lower gate pad electrode connected to the gate line and an upper gate pad electrode connected to the lower gate pad electrode within a first contact hole, the lower gate pad electrode being formed form the first conductive layer and the upper gate pad electrode being formed form a third conductive layer;
• a common pad having a lower common pad electrode connected to the first common line and an upper common pad electrode connected to the lower common pad electrode within a second contact hole, the lower common pad electrode being formed from the first conductive layer and the upper common pad electrode being formed from the third conductive layer;
• and
• a data pad having a lower data pad electrode connected to the data line and an upper data pad electrode connected to the lower data pad electrode within a third contact hole, the lower data pad electrode being formed from the second conductive layer and the upper data pad electrode being formed form the third conductive layer.