Investigation on the effects of Cu diffusion barrier material on the back-channel etched InGaZnO thin film transistors for large area high resolution LCD

Abstract

In this research, effects of Cu diffusion barrier material on the InGaZnO (IGZO) back channel etched (BCE) thin film transistor (TFT) were investigated. Mo, MoAlTi, and MoTi were used as a Cu diffusion barrier material. Thin film characteristics such as diffusion barrier property were analyzed, and electrical characteristics of the device were investigated. Among various Cu diffusion barrier materials, IGZO BCE-TFT with MoTi showed the best transfer characteristics. This difference in TFT performance is attributed to the fact that molybdenum oxide residue does not remain for only MoTi due to the difference of standard reduction potential between molybdenum oxide and Ti. This research will suggest the direction for designing Cu diffusion barrier layer.