Liquid crystal display device and method of fabricating the same
View Patent ↗A poly-silicon liquid crystal display device with an improved aperture ratio and a simplified method of fabricating the same are disclosed. A liquid crystal display device according to the present invention includes first and second substrates; a gate line on the first substrate; a data line crossing the gate line to define a pixel region; a thin film transistor (TFT) near the crossing of the gate and data lines, the TFT having a gate electrode, a source electrode and a drain electrode; a pixel electrode in the pixel region, the pixel electrode having a double-layer structure in which a metal layer is formed on a transparent conductive layer; a black matrix on the second substrate, the black matrix having an aperture portion partially overlapping the pixel electrode and the drain electrode; and a liquid crystal layer between the first and second substrates.
1. A method of fabricating a liquid crystal display device, comprising:
providing first and second substrates;
forming a buffer layer on the first substrate;
forming first and second active layers on the buffer layer;
forming a first insulating film on the first and second active layers;
forming a first conductive pattern including a gate electrode, a gate line, a storage line, and a pixel electrode, the first conductive pattern having a double-layer structure in which a metal layer is formed on a transparent conductive layer;
forming a second insulating film on the first conductive pattern;
forming source and drain contact holes exposing source and drain areas of the first active layer, and forming a transmission hole exposing the transparent conductive layer of the pixel electrode;
forming a data line, a source electrode, and a drain electrode on the second insulating film; and
forming a black matrix on the second substrate, the black matrix having an aperture portion partially overlapping the pixel electrode and the drain electrode.
2. The method of claim 1 , wherein the gate electrode connected to the gate line crosses the first active layer.
3. The method of claim 1 , wherein the storage line overlaps with the second active layer.
4. The method of claim 1 , wherein the pixel electrode is formed between the gate line and the storage line.
5. The method of claim 1 , wherein the drain electrode is connected to the drain area and the pixel electrode across the storage line.
6. The method of claim 1 , further comprising forming an alignment film on the data line and the source and drain electrodes.
7. The method of claim 1 , wherein forming the transmission hole includes:
patterning the second insulating film to define the transmission hole; and
exposing the transparent conductive layer by etching the metal layer of the pixel electrode through the transmission hole.
8. The method of claim 1 , wherein the metal layer of the pixel electrode surrounds the transparent conductive layer of the pixel electrode.
9. The method of claim 1 , wherein the drain electrode is formed along the storage line, and is adjacent to both sides of the data line.
10. The method of claim 1 , wherein the drain electrode surrounds one portion of the pixel electrode adjacent to the storage line.
11. The method of claim 1 , further comprising forming a bridge crossing the aperture portion.
12. The method of claim 11 , wherein the bridge covers a step portion of the drain electrode.
13. The method of claim 12 , wherein the bridge prevents a light leakage at the step portion of the drain electrode.
14. The method of claim 1 , wherein the aperture portion of the black matrix is formed in an outer portion of a first boundary of the pixel electrode and in an inner portion of a second boundary of the pixel electrode.
15. The method of claim 1 , further comprising forming a liquid crystal layer between the first and second substrates.