Electrically Tunable Wafer-Sized Three-Dimensional Topological Insulator Thin Films Grown by Magnetron Sputtering

Qixun Guo; Yu Wu; Longxiang Xu; Yan Gong; Yunbo Ou; Yang Liu; Leilei Li; Jiao Teng; Yu Yan; Gang Han; Dongwei Wang; Lihua Wang; Shibing Long; Bowei Zhang; Xun Cao; Shanwu Yang; Xuemin Wang; Yizhong Huang; Tao Liu; Guanghua Yu; Ke He

doi:10.1088/0256-307x/37/5/057301

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arXiv · 1901.02611

Electrically Tunable Wafer-Sized Three-Dimensional Topological Insulator Thin Films Grown by Magnetron Sputtering

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Abstract

Three-dimensional (3D) topological insulators (TIs) are candidate materials for various electronic and spintronic devices due to their strong spin-orbit coupling and unique surface electronic structure. Rapid, low-cost preparation of large-area TI thin films compatible with conventional semiconductor technology is key to the practical applications of TIs. Here, we show that wafer-sized Bi2Te3 family TI and magnetic TI films with decent quality and well-controlled composition and properties can be prepared on amorphous SiO2/Si substrates by magnetron cosputtering. The SiO2/Si substrates enable us to electrically tune (Bi1-xSbx)2Te3 and Cr-doped (Bi1-xSbx)2Te3 TI films between p-type and n-type behavior and thus study the phenomena associated with topological surface states, such as the quantum anomalous Hall effect (QAHE). This work significantly facilitates the fabrication of TI-based devices for electronic and spintronic applications.

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Qixun Guo, Yu Wu, Longxiang Xu, Yan Gong, Yunbo Ou, Yang Liu, Leilei Li, Jiao Teng, Yu Yan, Gang Han, Dongwei Wang, Lihua Wang, Shibing Long, Bowei Zhang, Xun Cao, Shanwu Yang, Xuemin Wang, Yizhong Huang, Tao Liu, Guanghua Yu, Ke He. 2019-01-09. Electrically Tunable Wafer-Sized Three-Dimensional Topological Insulator Thin Films Grown by Magnetron Sputtering. https://doi.org/10.1088/0256-307x%2F37%2F5%2F057301

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