Jian Jiaying, Chang Honglong, Xu Tao
School of Mechanical Engineering, Northwestern Polytechnical University, Xi'an 710072, China.
School of Materials Science and Chemical Engineering, Xi'an Technological University, Xi'an 710021, China.
Materials (Basel). 2019 Jan 9;12(2):198. doi: 10.3390/ma12020198.
To meet the need for preparing high-performance nano-optoelectronic devices based on single-layer MoS₂, the effects of the heating method (one-step or two-step heating) and the temperature of the MoO₃ source on the morphology, size, structure, and layers of an MoS₂ crystal grown on a sapphire substrate using chemical vapor deposition are studied in this paper. The results show that MoS₂ prepared by two-step heating (the heating of the S source starts when the temperature of the MoO₃ source rises to 837 K) is superior over that of one-step heating (MoO₃ and S are heated at the same time). One-step heating tends to form a mixture of MoO₂ and MoS₂. Neither too low nor too high of a heating temperature of MoO₃ source is conducive to the formation of MoS₂. When the temperature of MoO₃ source is in the range of 1073 K to 1098 K, the size of MoS₂ increases with the rise in temperature. A uniform large-sized triangle with a side length of 100 μm is obtained when the heating temperature of MoO₃ is 1098 K. The triangular MoS₂ crystals grown by the two-step heating method have a single-layer structure.
为满足制备基于单层二硫化钼（MoS₂）的高性能纳米光电器件的需求，本文研究了加热方式（一步加热或两步加热）以及三氧化钼（MoO₃）源温度对采用化学气相沉积法在蓝宝石衬底上生长的MoS₂晶体的形貌、尺寸、结构和层数的影响。结果表明，两步加热法（当MoO₃源温度升至837 K时开始加热硫源）制备的MoS₂优于一步加热法（MoO₃和硫同时加热）。一步加热容易形成二氧化钼（MoO₂）和MoS₂的混合物。MoO₃源的加热温度过高或过低都不利于MoS₂的形成。当MoO₃源温度在1073 K至1098 K范围内时，MoS₂的尺寸随温度升高而增大。当MoO₃的加热温度为1098 K时，可获得边长为100μm的均匀大尺寸三角形。通过两步加热法生长的三角形MoS₂晶体具有单层结构。
