Enhancing perovskite TFTs performance by optimizing the interface characteristics of metal/semiconductor contact

Abstract Organic–inorganic hybrid perovskite materials have recently attracted a great deal of research interest because of their outstanding properties. In this work, thin-film field-effect transistors (TFTs) based on organic–inorganic hybrid perovskite CH 3 NH 3 PbI 3 are proposed. The molybdenum oxide (MoO 3 ) is adopted as a buffer layer between metal electrodes and the active layer to improve the interface performance of these devices. As a result, TFTs field effect mobility increases from 1.06 to 3.88 cm 2 /V s and subthreshold slope decreases from 3.4 V/dec to 1.6 V/dec. It is demonstrated that the improved performance of the organic–inorganic hybrid perovskite TFTs with MoO 3 buffer layer can be attributed to the decrease of the hole injection barrier and the trap states density in the access region due to the doping effect. Moreover, we also suggest that the thin MoO 3 film can prevent the diffusion of the metal electrode atoms into CH 3 NH 3 PbI 3 channel layer, leading to the enhancement of the device performance.