Liquid crystal display device having structure of color filter on TFT and using in plane switching mode

1. A liquid crystal display device, comprising:

gate lines crossing data lines on a first substrate defining a pixel region;

at least one common electrode formed in the pixel region;

at least one pixel electrode in the pixel region, the at least one pixel electrode corresponding to the common electrode;

a color filter layer formed within the pixel region excluding the gate line and the data line;

a black matrix having at least three layers, an inner layer of the at least three layers being an electrode material.

2. The device of claim 1 , wherein the pixel electrode and the black matrix have the same laminated layers.

3. The device of claim 1 , wherein the at least three layers of the black matrix include a first layer of conductive opaque layer, a second layer of electrode material, and a third layer of reflective shielding layer in a sequential order.

4. The device of claim 3 , wherein the first layer is a Cr layer, the second layer is an ITO layer and the third layer is a CrOx layer.

5. The device of claim 1 , wherein the at least one common electrode is formed in the same layer as the gate lines.

6. The device of claim 1 , further comprising a passivation layer formed on the color filter layer, wherein the black matrix and the at least one pixel electrode are formed on the passivation layer.

7. A liquid crystal display device, comprising:

gate lines crossing data lines on a first substrate defining a pixel region;

at least one common electrode formed in the pixel region;

at least one pixel electrode in the pixel region, the at least one pixel electrode having at least three layers, and the at least one pixel electrode corresponding to the common electrode;

a color filter layer formed within the pixel region excluding the gate line and the data line;

a black matrix having a same at least three layers as the at least one pixel electrode, an inner layer of the at least three layers being an electrode material.

8. The device of claim 7 , wherein the at least three layers of the at least one pixel electrode include a first layer of conductive opaque layer, a second layer of electrode material, and a third layer of reflective shielding layer in a sequential order.

9. The device of claim 8 , wherein the first layer is a Cr layer, the second layer is an ITO layer and the third layer is a CrOx layer.

10. The device of claim 7 , wherein the at least one common electrode is formed in the same layer as the gate lines.

11. The device of claim 7 , further comprising a passivation layer formed on the color filter layer, wherein the black matrix and the at least one pixel electrode are formed on the passivation layer.