The research group led by Professor Wang Haibo from the College of Materials Science and Engineering, Jilin University has achieved a breakthrough in the field of tin-based perovskite field-effect transistors (FETs). To address the issue of high background carrier concentration in tin-based perovskite transistors, this study clarifies that background carriers originate not only from tin oxidation and tin vacancies but also from the migration of organic cations. Via hydrogen bond suppression and thin-film quality optimization, the resulting field-effect transistors deliver high carrier mobility and outstanding operational stability.

Figure 1. (a) FASnI₃ FETs fabricated with different tin compensators. Hydrogen bonding between F⁻ and FA⁺ ions effectively suppresses organic cation migration, endowing devices with favorable field-effect characteristics. (b) Tin-based perovskite transistors prepared with fluorinated low-dimensional organic cations exhibit superior device performance and operational stability.

Although hybrid organic-inorganic perovskites possess exceptional semiconducting properties, their practical deployment in field-effect transistors (FETs) remains constrained. Ion migration constitutes a critical bottleneck for perovskite transistors, as it may induce screening of the applied gate electric field and severe hysteresis. This work investigates the influence of ion migration on the performance of tin-based perovskite FETs. By comparing the effects of various Sn compensators, the study verifies that FA⁺ ion migration in FASnI₃ FETs triggers pronounced hysteresis and poor operational instability. This finding reveals a new fundamental understanding of tin-based perovskite transistors: the high background carrier concentration in FASnI₃ FETs arises from three sources—oxidation of Sn²⁺, tin vacancies, and FA⁺ cation migration. Hydrogen bonding between FA⁺ and F⁻ ions efficiently restrains ion migration, which simultaneously reduces background carrier density and enhances transistor operational stability. The tin-based perovskite transistors fabricated with fluorinated low-dimensional organic cation additives achieve an effective carrier mobility of 30 cm² V⁻¹ s⁻¹ and an on/off current ratio of 10⁷, alongside remarkable cycling stability during repeated testing.

Yang Wenshu, a doctoral candidate from the College of Materials Science and Engineering, Jilin University, is the first author of this paper. Professor Wang Haibo (Jilin University) and Researcher Qin Chuanjiang (Changchun Institute of Applied Chemistry, Chinese Academy of Sciences) serve as the corresponding authors. The authors sincerely acknowledge Professor Zhang Lijun for his valuable assistance and support to this research. This work was funded by the National Natural Science Foundation of China and the Natural Science Foundation of Jilin Province.