基于熔融玻璃的预沉积法生长毫米级单晶MoS2及WS2-MoS2异质结

MoS₂是一种具有优异光电性能和奇特物理性质的二维材料,在电子器件领域具有巨大的应用潜力.高效可控生长出大尺寸单晶MoS₂是该材料进入产业应用所必须克服的重大难关,而化学气相沉积技术被认为是工业化生产二维材料的最有效手段.本文介绍了一种利用磁控溅射预沉积钼源至熔融玻璃上,通过快速升温的化学气相沉积技术生长出尺寸达1 mm的单晶MoS₂的方法,并通过引入WO₃粉末生长出了二硫化钼与二硫化钨的横向异质结(WS₂-MoS₂).拉曼和荧光光谱仪测试表明所生长的样品具有较好的晶体质量.利用转移电极技术制备出了背栅器件样品并对其进行了电学测试,在室温常压下开关比可达10~5,迁移率可达4.53 cm~2/(V·s).这种低成本高质量的大尺寸材料生长方法为二维材料电子器件的大规模应用找到了出路.

Milimeter-level MoS2 monolayers and WS2-MoS2 heterojunctions grown on molten glass by pre-chemical vapor deposition

Molybdenum disulfide(MoS₂),as a kind of two-dimensional(2D)material with novel physical properties and excellent electrical performances,has great potential applications in electronic devices.Efficient and controllable growth of large-size single crystal MoS₂ is a major difficulty that must be overcome towards scalable production.Chemical vapor deposition(CVD)is considered as the most promising means for industrial production of 2D materials.Here in this work,the high-quality and millimeter-level single crystal MoS₂monolayer grows on molten glass by the pre-chemical vapor deposition,in which MoO₃ film deposited on the molten glass is used as Mo precursor instead of MoO₃ powder.In addition,by introducing WO₃ powder into such a CVD system,MoS₂-WS₂ lateral heterojunctions can also be obtained.Raman and PL measurements indicate that the as-grown MoS₂ monolayer samples possess high quality.The Back-gate FETs are fabricated on SiO₂/Si substrates by using transferring elelctrode methods to investigate the electrical properties of the as-grown MoS₂ crystals.At room temperature and atmosphere pressure,the on-off ratio can reach 10⁵ and the carrier mobility can arrive at 4.53 cm²/(V·s).The low-cost and high-quality large-size material growth method pave the way for the scalable production of such a 2D material based electronic devices.