Liquid crystal display device and fabricating method thereof

1. A method of fabricating a liquid crystal display device, comprising:

forming a poly-crystalline silicon layer on a substrate;

forming a photoresist pattern on the poly-crystalline silicon layer;

simultaneously dry-etching the poly-crystalline silicon layer and ashing the photoresist pattern using hydrogen bromide gas, chlorine gas, sulfur hexafluoride gas, Br 2 , and oxygen gas to form a semiconductor layer, wherein an edge portion of the semiconductor layer has a side surface of a substantially tapered shape;

forming a gate insulating layer covering the semiconductor layer;

forming a gate electrode on the gate insulating layer;

forming a channel portion and ohmic contact portions in the semiconductor layer, the ohmic contact portions being disposed at both sides of the channel portion;

forming source and drain electrodes contacting the semiconductor layer; and

forming a pixel electrode contacting the drain electrode.

2. The method according to claim 1 , wherein the side surface has an angle θ 2 of about 30 to about 60 degrees with respect to a plane of the substrate.

3. The method according to claim 1 , wherein forming the ohmic contact portions includes doping the semiconductor layer with n+ or p+-ions using the gate electrode as a doping mask after forming the side surface of the tapered shape.

4. The method according to claim 1 , wherein the gate insulating layer has substantially a uniform thickness.

5. The method according to claim 1 , wherein forming the semiconductor layer includes forming lightly doped drain portions substantially between the channel portion and the ohmic contact portions.