Molecular Interlayer for High‐Performance and Stable 2D Tin Halide Perovskite Transistor

Abstract Tin (Sn) halide perovskites present considerable potential for the advancement of high‐performance p‐channel field‐effect transistors (FETs), attributable to their low hole effective mass and reduced carrier scattering. However, their intrinsic instability has impeded their ability to achieve the anticipated performance benchmarks. In this study, molecular interlayers are designed that not only passivate surface defects in Sn perovskites through their functional groups, leading to improved film formation and consequently enhanced performance and stability but also reduce the energy barrier at the source and drain interfaces through their strong dipole moments, thereby enhancing carrier transport. These synergistic effects result in FET devices exhibiting remarkable performance metrics, including effective mobility exceeding 11 cm ² V ⁻¹ s ⁻¹ and an on/off ratio greater than 1.3 × 10 ⁷ while securing exceptional durability and reproducibility. Furthermore, the hydrophobic characteristics of the surface interlayer confer superior storage stability.