Abstract: A method for fabricating a thin film transistor (TFT), including the steps of forming a semiconductor layer on a substrate; forming an insulating oxide layer on the semiconductor layer; forming a polysilicon layer on the insulating layer; etching the polysilicon layer to form a gate electrode having tapered sides; carrying out an oxidation process on exposed surfaces of the gate electrode and the polysilicon layer surrounding the gate electrode resulting in the oxide layer thereby formed being thicker below the bottom edges of the tapered sides of the gate electrode than on other portions of the gate electrode and the surrounding polysilicon layer; and forming impurity regions in the semiconductor layer on opposite sides of the gate electrode to thereby form a transistor. The TFT thereby formed has a tapered gate and reduced OFF current.