化学气相沉积法较低温度下制备层状硫化钼薄膜的研究

Study on Layered MoS2 Films Grown by Chemical Vapor Deposition at Relatively Low Temperatures

二硫化钼具有类似石墨烯的层状结构,是一种被广泛研究的过渡金属硫族化合物。层状二硫化钼是一种具有较高带隙的半导体,其具有好的光致发光特性以及光电子学特性,在晶体管、光伏、传感器件以及光催化分解水制备氢气等领域具有潜在的应用价值。目前,较高质量的二硫化钼层状薄膜主要是通过高温化学气相沉积法制备,一般制备温度较高,在850~1000℃。本实验利用化学气相沉积法分别在650℃、675℃、700℃、725℃和750℃条件下制备层状二硫化钼薄膜。通过对不同温度下制备的样品进行光学形貌测试及拉曼光谱分析,得出在较低温度下温度对制备二硫化钼薄膜的形貌和单个片层的尺寸具有显著的影响,其中在725℃时制备的层状薄膜形貌和尺寸都较好。本工作为在较低温度下制备出高质量层状MoS2薄膜打下了较好的基础。

MoS 2 is 2D layered transition metal dichalcogenides(TMDs),which has a layered structure similar to graphene,has been widely investigated.MoS 2 will turn to a direct band gap semiconductor with a bandgap as high as 1.9 eV when reduced to a single-layered structure,and it also has a strongly enhanced photoluminescence effect and excellent nano-and opto-electronic properties,this makes single layer MoS 2 a promising material for the next generation of nanoelectronics and optoelectronics and also a potential material for highly efficient photo catalytic H 2 generation.As for preparation,chemical vapor deposition has been the most commonly used method for layered MoS 2 growth.However,it is usually performed under a high temperature ranged around 850-1 000℃,which is very energy consumed.Here we explored the relatively low temperature situation,and have grown layered MoS 2 films by chemical vapor deposition under the temperature under 650℃,675℃,700℃,725℃and 750℃.The as prepared samples were characterized with optical microscope(OM)and Raman spectroscopy.The results show that MoS 2 can be grown under a temperature even low as 650℃,and the MoS 2 triangles grown under 725℃have the largest average area and the best morphology.The results of this experiment show that it is possible to grow MoS 2 few layered films under a relatively low temperature,which would save more energy and be economic.