Silicon-compatible low resistance S/D technologies for high-performance top-gate self-aligned InGaZnO TFTs with UTBB (ultra-thin body and BOX) structures

Abstract

We have fabricated high-performance self-aligned top-gate InGaZnO TFTs with novel silicon-like source and drain (S/D) parasitic resistance (RSD) reduction processes. Ar ion implantation (Ar I/I) formed S/D extension layers and reduced RSD by inducing high-density carriers. First demonstration of self-aligned S/D metallization processes on InGaZnO surface (In-Ti alloy formation), just like silicidation, realized further RSD reduction. In addition, threshold voltage (Vth) controllability by back-gate bias was enhanced by adopting thin InGaZnO body and BOX. Successful applications of these booster technologies developed for Si LSIs enable us to fabricate high-performance top-gate scaled InGaZnO TFT in 3D LSI.