Solution-Processed Heterojunction Oxide Thin-Film Transistors for Displays

In this study, we investigate the effect of channel layer thickness on the performance of InZnO/AlInZnO (IZO/AIZO) heterojunction thin-film transistors (TFTs) fabricated using a solution-based method. The conduction band offset at the heterointerface significantly influences the operating characteristics of TFTs, which can be modulated by adjusting the layer thickness, as confirmed through both experimental and computational analysis. Due to the formation of a quasi-two-dimensional electron gas system at the IZO/AIZO interface, optimized TFTs show a high mobility of ∼ 18cm²/Vs, a near-zero turn-on voltage and a current on/off ratio approaching 10⁸. The work offers valuable insights into the operating principles of oxide-based heterojunction TFTs and highlights their potential for next-generation printable displays.