Electrical and Structural Characterization of Self-Aligned InGaZnO Thin-film Transistors Fabricated by Excimer Laser Irradiation

We conducted electrical and structural characterization of a self-aligned InGaZnO (IGZO) thin-film transistor (TFT) fabricated by selectively reducing the resistance of the source and drain (S/D) regions by backside excimer laser irradiation. We present the influence of the resistance of the S/D regions on the transfer characteristics and discuss the applicability of our resistance reduction method to the self-aligned oxide TFT fabrication process. In our proposed method, since the low-resistance regions are formed directly by using the gate electrode as a mask, the positions of the S/D regions can be accurately set. We demonstrate this by analyzing the spreading resistance and height profiles for the IGZO film.