A Novel TFT with Organic-Inorganic Hybrid Perovskite Channel Layer

Thin-film field-effect transistors (TFTs) are an essential part of a variety of modern electronics. Interestingly, organic-inorganic hybrid perovskite (OHP) material combines the excellent carrier mobility of inorganic semiconductors and the fabricability of organic materials. Herein a thin-film field-effect transistor using CH3NH3PbI3 as the semiconducting channel was demonstrated. A feasible strategy was presented by modifying the gold electrode with 4-fluorobenzenethiol to eliminate the hole injection barrier between the electrode and CH3NH3PbI3. In addition, we also improved the interfacial characteristics between the gold electrode and the perovskite film by using molybdenum oxide (MoO3) buffer layer. Finally, high-k alumina (Al2O3) was utilized to substitute silicon oxide (SiO2) as the dielectric layer to reach low operating voltage in OHP TFTs. The representative TFT showed superior performance with the subthreshold swing (SS), on/off current ratio and linear field-effect mobility (μFE) values of 0.49 V/dec, 104 and 21.41 cm2/V, respectively. Simple low-temperature processing technology and prominent device performance made this OHP TFT have broad prospects for low-cost, large-area, and flexible applications. The device performance is supposed to be further enhanced through molecular engineering in the organic and inorganic components of the hybrid perovskite to fulfil high speed applications.