Recent advances in halide perovskite material classes for field-effect transistors

This review examines the recent progress in thin-film field-effect transistors (FETs) that employ 2D halide perovskites as the active layer. Attention is concentrated on the molecular chemistry that affects lattice integrity and interface energetics. The incorporation of spacer cations with medium alkyl chains, π-conjugated bonds, diammonium linkers, or chiral centers has significantly improved the layered network, minimized vacancy formation, and restricted ion migration. Additional additives that supplied sulfur donors or extra metal halides improved crystal continuity and preserved the desired oxidation state of tin, resulting in films with smooth grains and low trap densities. Interlayers displaying significant dipole moments aligned the perovskite work function with gold (Au) electrodes, enabling close ohmic contact. Simultaneously, cross-linked polymer dielectrics and protective 2D caps significantly reduced leakage, prevented moisture ingress, and controlled ionic drift. The combination of chemical and process engineering resulted in transfer characteristics that demonstrate narrow hysteresis, stable threshold voltages, and improved mobility. The capacity to regulate gating via light and the reversible interaction with oxygen demonstrated additional adaptability; nonetheless, the intrinsic ionic flexibility underscored the need for strategies that guarantee enduring consistency. Recent results highlight 2D perovskites as among the most promising solution-processed semiconductors for flexible electronics.