Threshold Voltage Control of In-Ga-Zn-O TFT without Thermal Annealing Process by Inductively Coupled Plasma Sputtering System

This report shows that an amorphous a-InGaZnO (IGZO) thin film transistor (TFT) can control the threshold voltage ( Vth) without thermal annealing process when depositing a-IGZO using an inductively coupled plasma (ICP) sputtering system. A two layer a-IGZO TFT with controlled oxygen concentrations was fabricated using the ICP sputtering system developed for high density thin film deposition. As a result of evaluation of TFT characteristics, a-IGZO TFTs with changed Vth could be fabricated without a thermal annealing process.