| 摘要 |
A method for manufacturing a polysilicon TFT(Thin Film Transistor) and a method for manufacturing an LCD(Liquid Crystal Display) device by using the same are provided to enable a metal layer to perform simultaneously a mask role for etching an amorphous silicon layer and a catalyst role for crystallizing the amorphous silicon layer in forming the metal layer in a predetermined of the upper part of the amorphous silicon layer, thereby simplifying the process. A method for manufacturing a polysilicon TFT comprises the following steps of: forming an amorphous silicon layer on a substrate(111); forming a first self alignment layer in a predetermined portion of the upper part of the amorphous silicon layer; forming a first metal layer on the amorphous silicon layer exposed between the first self alignment layer; removing the first self alignment layer; etching the amorphous silicon layer by using the first metal layer as a mask and forming a semiconductor layer(114a); crystallizing the amorphous silicon layer by using the first metal layer as a catalyst; forming separately source and drain electrodes(115a,115b) in both sides of the polysilicon layer; forming a gate insulating layer(113) in the front of the substrate including the source and drain electrodes; and forming a gate electrode(112a) on the gate insulating layer between the source and drain electrodes. |
