Single-crystalline metal-oxide dielectrics for top-gate 2D transistors

Abstract Two-dimensional (2D) structures composed of atomically thin materials with high carrier mobility have been studied as candidates for future transistors 1–4 . However, owing to the unavailability of suitable high-quality dielectrics, 2D field-effect transistors (FETs) cannot attain the full theoretical potential and advantages despite their superior physical and electrical properties 3,5,6 . Here we demonstrate the fabrication of atomically thin single-crystalline Al 2 O 3 (c-Al 2 O 3 ) as a high-quality top-gate dielectric in 2D FETs. By using intercalative oxidation techniques, a stable, stoichiometric and atomically thin c-Al 2 O 3 layer with a thickness of 1.25 nm is formed on the…