METHOD FOR FABRICATING THIN FILM TRANSISTOR INCLUDING CRYSTALLINE SILICON ACTIVE LAYER

摘要

PURPOSE: A method for fabricating a thin film transistor(TFT) including a crystalline silicon active layer is provided to prevent a substrate of the TFT from being deformed and damaged by a heat treatment process, by crystallizing the substrate at a temperature of 300-700 deg.C in which glass is transformed. CONSTITUTION: The substrate(20) is prepared. An amorphous silicon layer as an active layer which forms a source region(21S), a drain region(21D) and a channel region(21C) of the TFT is deposited on the substrate. A gate insulation layer(22) and a gate electrode(23) are formed on the substrate and the active layer. Dopants are injected into the source and drain regions of the active layer and a metal induced lateral crystallization(MILC) source metal is applied. A heat treatment process is performed on the substrate and the active layer to transform the amorphous silicon constituting the active layer into crystalline silicon. A contact insulation layer is formed on the substrate, the active layer and the gate electrode. A contact hole is formed in the contact insulation layer to expose a part of the source and drain regions. A contact electrode which electrically connects the source and drain regions to the exterior through the contact hole is formed. The MILC source metal is offset to the channel region by using a mask with no photoresist layer.