Uniform High-k Amorphous Native Oxide Synthesized by Oxygen Plasma for Top-Gated Transistors

The integration of high-k gate dielectrics with two-dimensional (2D) semiconducting channel materials is essential for high-performance and low- power electronics. However, the conformal deposition of a uniform high-k dielectric with sub-1 nm equivalent oxide thickness (EOT) and high interface quality on high-mobility 2D semiconductors is still challenging. Here, we report a facile approach to synthesize a uniform high-k (epsilon(r) similar to 22) amorphous native oxide Bi2SeOx on the high-mobility 2D semiconducting Bi2O2Se using O-2 plasma at room temperature. The conformal native oxide can directly serve as gate dielectrics with EOT of similar to 0.9 nm, while the original properties of underlying 2D Bi2O2Se is preserved. Furthermore, high-resolution area-selective oxidation of Bi2O2Se is achieved to fabricate discrete electronic components. This facile integration of a high-mobility 2D semiconductor and its high-k native oxide holds high promise for next-generation nanoelectronics.