Charge Transport in All‐Inorganic CuInSe ₂ Nanocrystal Transistors: Linking Material Design and Device Performance

Solution‐processable semiconductor nanocrystals (NCs) offer a versatile, highly tunable platform for low‐cost, next‐generation electronics. However, their integration into field‐effect transistors (FETs) remains limited by the challenge of optimizing synthesis, surface chemistry, and charge transport. In this work, CuInSe 2 NCs are synthesized, and their organic, insulating ligand environment is exchanged with short inorganic ligands such as sulfides, to enable efficient interparticle coupling. The all‐inorganic dispersions are spin‐coated and top‐contacted to fabricate fully functioning FETs. Reference samples exhibit saturation mobilities of µ sat = 2.30 ± 0.76 × 10 −3 cm 2 V −1 s −1 and a current modulation R on/off = 10.4. Systematic variation of key parameters—including NC size, ligand chemistry, film thickness, and transistor geometry—provides a comprehensive understanding of the structure‐property relationships, enhancing the final FET performance up to µ sat = 12.93 ± 1.23 × 10 −3 cm 2 V −1 s −1 . This study presents a knowledge platform for advancing NC‐based electronics toward practical applications.