METHOD OF FORMING POLY SILICON CRYSTALLIZATION AND METHOD OF MANUFACTURING THIN FILM TRANSISTOR USING THE METHOD

摘要

A method for forming a poly silicon crystal and a method for manufacturing a thin film transistor using the same are provided to manufacture the TFT(Thin Film Transistor) without using an amorphous silicon layer by using the poly silicon crystal, which is elongated in one direction, as an active layer of the TFT. A laser beam is irradiated on a scan line with a linewidth of a few micrometers on an amorphous silicon layer(30). First and second crystals are formed. The first crystal is grown along a linewidth direction. The second crystal is grown in an opposite direction with respect to the linewidth direction and forms a grain boundary with the first crystal. The laser beam is irradiated on the scan line, which is moved in the linewidth direction to include the grain boundary, such that a third crystal is formed. The third crystal is grown from a portion of the first crystal as a single grain in the linewidth direction.