Quantum-Mechanical Analysis of Amorphous Oxide-Based Thin-Film Transistors

In this paper, we analyzed the electrical characteristics of amorphous oxide-based thin-film transistors (TFTs) with extremely thin active layers using a quantum-mechanical method (density gradient method) and a technology computer-aided design simulator. We observed that the evaluation of the TFT performance using the classical method resulted in errors, especially, when the interfacial-defect density of states was high. The electrical characteristics of the TFTs are influenced differently by the bulk and interfacial states when the quantum-mechanical effect is considered. Therefore, it is essential to apply the quantum effect to analyze the electrical characteristics of amorphous oxide-based TFTs with extremely thin active layers.