Solution-processed IGZO field-effect transistors with a three-step laser annealing process

In this paper, a three-step annealing process was employed to treat IGZO thin-film field-effect transistors (TFTs). We observed that TFTs prepared by an initial high-temperature thermal annealing exhibited a low threshold voltage. By employing a second-step low-temperature annealing, the threshold voltage of the TFT was positively shifted, demonstrating improved turn-off characteristics. However, after this process, a significant decrease in TFT mobility and a change in threshold voltage were observed. By introducing a third 633 nm laser annealing technique, we managed to control the threshold voltage and improve mobility. To investigate the mechanism of the changes in TFT performances up to different post-annealing processes, a series of characterization techniques were employed to explain the TFT performance changes.