Development of annealing process for solution-derived high performance InGaZnO thin-film transistors

The influences of the annealing process on solution-derived InGaZnO thin-film transistors (TFTs) were investigated. Operation characteristics of IGZO TFTs were obtained from high temperature processes: rapid thermal annealing (RTA) at 600 °C and conventional thermal annealing (CTA) at 500 °C. It is found that the RTA increases the on-current and off-current of TFTs. The CTA decreases off-current and improves the interfacial property. Meanwhile, a two-step annealing process, comprising RTA and CTA, increases on-current and decreases off-current and is considered as the optimal annealing procedure. Another two-step annealing process, comprising CTA and RTA, increases on-current but increases off-current, simultaneously.