A Single‐Crystal Antimony Trioxide Dielectric for 2D Field‐Effect Transistors

Abstract The remarkable potential of two‐dimensional (2D) materials in sustaining Moore's law has sparked a research frenzy. Extensive efforts have been made in the research of utilizing 2D semiconductors as channel materials in field‐effect transistors. However, the next generation of integrated devices requires the integration of gate dielectrics with wider bandgaps and higher dielectric constants. Here, insulating α‐Sb ₂ O ₃ single‐crystal nanosheets are synthesized by one‐step chemical vapor deposition method. Importantly, the α‐Sb ₂ O ₃ single‐crystal dielectric exhibits a high dielectric constant of 11.8 and a wide bandgap of 3.78 eV. Besides, the atomically smooth interface between α‐Sb ₂ O ₃ and MoS ₂ enables the fabrication of dual‐gated field‐effect transistors with the top gate dielectric of α‐Sb ₂ O ₃ nanosheets. The field‐effect transistors exhibit a switching ratio of exceeding 10 ⁸ , which achieves the manipulation of field‐effect transistors by using 2D dielectric materials. These results hold significant implications for optimizing the performances of 2D devices and innovating microelectronics.