Performance Enhancement of Solution-Processed p-Type CsPbBr3 TFT by Ultraviolet-Ozone Treatment

As a pure inorganic perovskite material, CsPbBr3 exhibits the advantages of high optical gain, low nonradiation loss, and ambient preparation. In this work, the p-type CsPbBr3 perovskite thin film was prepared by solution process in the air, and the thin-film transistors (TFTs) based on CsPbBr3 were integrated. The effects of ultraviolet-ozone (UVO) treatment on the electrical and optical properties for the CsPbBr3 TFTs were investigated, and the residual oxygen and carbon-related impurities in CsPbBr3 thin film can be removed after UVO treatment. It is found that the CsPbBr3 TFT treated by UVO for 3 min demonstrates the highest electrical and optical performance, including the on/off current ratio of $10^{{5}}$ , hole mobility of 1.08 cm $^{{2}} \cdot \text {V}^{-{1}}\cdot \text {s}^{-{1}}$ , responsivity of 1.2 A/W, specific detectivity of $4.52\times 10^{{12}}$ Jones, and external quantum efficiency (EQE) of 266%. Meanwhile, the TFTs based on CsPbBr3 with UVO treatment exhibit high environmental stability after storage in air for 30 days. The UVO treatment is effective for surface passivation of the CsPbBr3 thin film, and the performance of the TFT can be optimized correspondingly. This work provides a promising approach for the development of all inorganic, low-cost, and high-performance perovskite TFTs and photodetectors in the future.