Influence of annealing temperature on the optoelectronic properties of ITZO thin films

In this work, the electrical conductivity and optical transparency of the In-Sn-Zn-O (ITZO) films annealed at different temperatures were investigated. The results show that the ITZO films transformed from amorphous phase to crystalline phase after annealed in the air. The transmittance of the films improves significantly and all exceed 88%. Meanwhile, the annealed ITZO films exhibit a significant enhancement in conductivity. In particular, ITZO film annealed at 650 °C has high electrical conductivity (∼4.94 × 102S cm-1) and an excellent figure of merit (∼5.94 × 10-4Ω-1). Moreover, ITZO thin film transistors were prepared and their performance was tested. After annealing, the high electrical properties of the active layer make the gate regulation ability of the thin film transistors degrade. The annealed films with excellent optoelectronic properties can be applied to transparent electrodes.