Large‐Area and High‐Quality 2D Transition Metal Telluride

• DOI: 10.1002/adma.201603471
• Publication Date: 2016-11-17T12:56:43Z
• Authors: Jiadong Zhou; Fucai Liu; Junhao Lin; Xiangwei Huang; Juan Xia; Bowei Zhang; Qingsheng Zeng; Hong Wang; Chao Zhu; Lin Niu; Xuewen Wang; Wei Fu; Peng Yu; Tay‐Rong Chang; Chuang‐Han Hsu; Di Wu; Horng‐Tay Jeng; Yizhong Huang; Hsin Lin; Zexiang Shen; Changli Yang; Li Lu; Kazu Suenaga; Wu Zhou; Sokrates T. Pante...; Guangtong Liu; Zheng Liu
• Keywords: Condensed Matter - Materials Science; Materials Science (cond-mat.mtrl-sci); FOS: Physical sciences; 02 engineering and technology; 2D materials; 01 natural sciences; 0104 chemical sciences; Chemical vapor deposition; 0210 nano-technology

Atomically thin transitional metal ditellurides like WTe2 and MoTe2 have triggered tremendous research interests because of their intrinsic nontrivial band structure. They are also predicted to be 2D topological insulators and type-II Weyl semimetals. However, most of the studies on ditelluride atomic layers so far rely on the low-yield and time-consuming mechanical exfoliation method. Direct synthesis of large-scale monolayer ditellurides has not yet been achieved. Here, using the chemical vapor deposition (CVD) method, we demonstrate controlled synthesis of high-quality and atom-thin tellurides with lateral size over 300 ��m. We found that the as-grown WTe2 maintains two different stacking sequences in the bilayer, where the atomic structure of the stacking boundary is revealed by scanning transmission electron microscope (STEM). The low-temperature transport measurements revealed a novel semimetal-to-insulator transition in WTe2 layers and an enhanced superconductivity in few-layer MoTe2. This work paves the way to the synthesis of atom-thin tellurides and also quantum spin Hall devices.