Tellurization Velocity-Dependent Metallic-Semiconducting-Metallic Phase Evolution in Chemical Vapor Deposition Growth of Large-Area, Few-Layer MoTe2.
Phase engineering of two-dimensional (2D) transition metal dichalcogenides (TMDs) such as MoTe2offers tremendous opportunities in various device applications. However, most of the existing methods so far only address the small-area local phase change or the growth of certain kinds of phases of MoTe2film by laser irradiation, mechanical strain, or procursor type. Obtaining facile, tunable, reversible, and continuous-phase transition and evolution between different phases in direct growth of large-area, few-layer MoTe2still remains challenging. Here, we develop a facile method to achieve phase control and transition and report a highly tunable, tellurization velocity-dependent metallic-semiconducting-metallic phase evolution in chemical vapor deposition (CVD) growth of large-area, few-layer MoTe2. We found four different phase stages, including two different types of coexistence phases of both 2H and 1 T' phases, 100% 2H phase, and 100% 1T' phase, would emerge, relying on the adopted tellurization velocity. Importantly, the tellurization velocity should be extremely controlled to obtain 100% 2H phase MoTe2, while 100% 1T' phase requires a fast tellurization velocity. We further found that such metallic-semiconducting-metallic phase evolution took place with a homogeneous spatial distribution and differs from previous reports in which obvious phase separations are usually found during the phase transition. The resulting MoTe2shows high quality with room-temperature mobility comparable with mechanically exfoliated materials. The results might impact large-scale phase engineering of TMDs and other 2D materials for Weyl semimetal topological physics and potential 2D semiconductor device applications.
Center for Joining and Electronic Packaging, State Key Laboratory of Material Processing and Die & Mold Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology , Wuhan 430074, P.R. China.
Li
L
Yang
Center for Joining and Electronic Packaging, State Key Laboratory of Material Processing and Die & Mold Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology , Wuhan 430074, P.R. China.
Wenfeng
0000-0001-9487-9375
W
Zhang
Center for Joining and Electronic Packaging, State Key Laboratory of Material Processing and Die & Mold Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology , Wuhan 430074, P.R. China.
Jie
J
Li
Center for Joining and Electronic Packaging, State Key Laboratory of Material Processing and Die & Mold Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology , Wuhan 430074, P.R. China.
Shuai
S
Cheng
Center for Joining and Electronic Packaging, State Key Laboratory of Material Processing and Die & Mold Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology , Wuhan 430074, P.R. China.
Zijian
Z
Xie
Center for Joining and Electronic Packaging, State Key Laboratory of Material Processing and Die & Mold Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology , Wuhan 430074, P.R. China.
Haixin
0000-0001-9621-4457
H
Chang
large-area synthesis; metallic−semiconducting−metallic phase transition; phase engineering; two-dimensional materials