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

Teng Tu; Yichi Zhang; Tianran Li; Jia Yu; Lingmei Liu; Jinxiong Wu; Congwei Tan; Jilin Tang; Yan Liang; Congcong Zhang; Yumin Dai; Yu Han; Keji Lai; Hailin Peng

doi:10.1021/acs.nanolett.0c02951

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

Nano Lett. 2020 Oct 14;20(10):7469-7475. doi: 10.1021/acs.nanolett.0c02951. Epub 2020 Sep 28.

Authors

Teng Tu¹, Yichi Zhang¹, Tianran Li¹, Jia Yu², Lingmei Liu³, Jinxiong Wu^{1

4}, Congwei Tan⁵, Jilin Tang⁵, Yan Liang¹, Congcong Zhang¹, Yumin Dai¹, Yu Han³, Keji Lai², Hailin Peng¹

Affiliations

¹ Center for Nanochemistry, Beijing Science and Engineering Center for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
² Department of Physics, University of Texas at Austin, Austin, Texas 78712, United States.
³ Advanced Membranes and Porous Materials (AMPM) Center, Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
⁴ Tianjin Key Lab for Rare Earth Materials and Applications, Center for Rare Earth and Inorganic Functional Materials, School of Materials Science and Engineering, National Institute for Advanced Materials, Nankai University, Tianjin 300350, China.
⁵ Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China.

PMID: 32881534
DOI: 10.1021/acs.nanolett.0c02951

Abstract

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 (ε_r ∼ 22) amorphous native oxide Bi₂SeO_x on the high-mobility 2D semiconducting Bi₂O₂Se using O₂ plasma at room temperature. The conformal native oxide can directly serve as gate dielectrics with EOT of ∼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.

Keywords: 2D materials; Bi2O2Se; high-k; native oxide; oxygen plasma; transistors.