Selective phase growth and precise-layer control in MoTe2
Selective phase growth and precise-layer control in MoTe2
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DOI：
10.1038/s43246-020-00048-4
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发表时间：
2020-07-24
影响因子：
7.8
通讯作者：
Ganin, Alexey Y.
中科院分区：
文献类型：
--
作者：
Fraser, James P.;Masaityte, Liudvika;Ganin, Alexey Y.
过渡金属二硫属化物的微小结构变化可以对其电子性质产生显著影响。这使得对关键参数的追求，使2D MoTe 2系统中的竞争金属和半导体相之间的选择性选择引人注目。在此，我们报告的最佳条件下，在该初始种子层的选择决定的类型的晶体结构的原子级薄的MoTe 2薄膜生长的化学气相沉积（CVD）。当Mo金属用作种子层时，半导体2 H-MoTe 2是唯一的产物。相反，MoO 3导致金属1 T-MoTe 2的优先生长。对相生长的控制允许在一个CVD反应期间在单个衬底上同时沉积2 H-MoTe 2和1 T '-MoTe 2相。此外，罗丹明6 G染料可以使用低至5 nM浓度的少层1 T '-MoTe 2膜检测，表明表面增强拉曼光谱（Sers）具有比本体1 T'-MoTe 2高几个数量级的灵敏度。
Minor structural changes in transition metal dichalcogenides can have dramatic effects on their electronic properties. This makes the quest for key parameters that enable a selective choice between the competing metallic and semiconducting phases in the 2D MoTe2 system compelling. Herein, we report the optimal conditions at which the choice of the initial seed layer dictates the type of crystal structure of atomically-thin MoTe2 films grown by chemical vapour deposition (CVD). When Mo metal is used as a seed layer, semiconducting 2H-MoTe2 is the only product. Conversely, MoO3 leads to the preferential growth of metallic 1T-MoTe2. The control over phase growth allows for simultaneous deposition of both 2H-MoTe2 and 1T '-MoTe2 phases on a single substrate during one CVD reaction. Furthermore, Rhodamine 6G dye can be detected using few-layered 1T '-MoTe2 films down to 5 nM concentration, demonstrating surface enhanced Raman spectroscopy (SERS) with sensitivity several orders of magnitude higher than for bulk 1T '-MoTe2.