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

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-Sb₂O₃ single-crystal nanosheets are synthesized by one-step chemical vapor deposition method. Importantly, the α-Sb₂O₃ 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-Sb₂O₃ and MoS₂ enables the fabrication of dual-gated field-effect transistors with the top gate dielectric of α-Sb₂O₃ nanosheets. The field-effect transistors exhibit a switching ratio of exceeding 10⁸, 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.