The optimization of organic-inorganic perovskite films by annealing atmosphere for applications in transistors.

We investigated the impact of annealing atmosphere on the properties of organic-inorganic perovskite films systematically, and the mechanism is elucidated in perspective of crystallization kinetics of perovskite. It is found that the kind of gas, the state of the gas and the existence of solvent during annealing can affect the crystallization process of perovskite films, which therefore influence the morphology of perovskite films. In addition, the perovskite-based thin-film field-effect transistors were fabricated in different heating environment. It was discovered that the effect of annealing atmosphere on the performance of transistors is consistent with that on the crystallization qualities of perovskite films, which further confirms the influence of annealing atmosphere on the electronic properties of perovskite films. We also found that the type of gas has impact on the electronic properties of perovskite thin films probably by influencing the defects in the surface of perovskite films. Furthermore, it is notable that we confirmed that perovskite based transistors, of which the active layer was completely fabricated in air, show better performance, which is beneficial for commercial production of perovskite based transistors with low cost. [ABSTRACT FROM AUTHOR]