Enhancing Stability and Performance in Tin‐Based Perovskite Field‐Effect Transistors Through Hydrogen Bond Suppression of Organic Cation Migration

Abstract Ion migration poses a substantial challenge in perovskite transistors, exerting detrimental effects on hysteresis and operational stability. This study focuses on elucidating the influence of ion migration on the performance of tin‐based perovskite field‐effect transistors (FETs). It is revealed that the high background carrier density in FASnI₃ FETs arises not only from the oxidation of Sn²⁺ but also from the migration of FA⁺ ions. The formation of hydrogen bonding between FA⁺ and F⁻ ions efficiently inhibits ion migration, leading to a reduction in background carrier density and an improvement in the operational stability of the transistors. The strategy of hydrogen bond is extended to fluorine‐substituted additives to improve device performance. The incorporation of 4‐fluorophenethylammonium iodide additives into FETs significantly minimizes the shift of turn‐on voltage during cyclic measurements. Notably, an effective mobility of up to 30 cm² V⁻¹ s⁻¹ with an I_on/off ratio of 10⁷ is achieved. These findings hold promising potential for advancing tin‐based perovskite technology in the field of electronics.