摘要
Large-scale synthesis of high-quality two dimensional(2D)semiconductors,such as molybdenum disulfide(MoS_(2)),is a prerequisite for their lab-to-fab transition.It is crucial to systematically explore and understand the influence of key synthetic conditions on the nucleation,uniformity,and quality of MoS_(2) wafers.Here,we report the epitaxial growth of high-quality and uniform monolayer MoS_(2) films on 2-in c-plane sapphire by chemical vapor deposition(CVD)method under optimized growth conditions(0–1 mg NaCl,adequate S/Mo ratio,and the addition of 0–1 sccm O2).We systematically explore the influence of critical synthetic conditions on the nucleation,and stitching of MoS_(2) domains over the wafer scale,including the dosage of the alkali metal salt NaCl additive,the evaporation temperature of MoO_(3),the distance between MoO_(3) and the substrate,and the flow rate of O_(2).Among them,the dosage of NaCl and the S/Mo ratio have important influences on the quality and film coverage of MoS_(2),while the flow rate of O_(2) plays a key role in controlling the nucleation density and domain size.We further discovered that a-plane sapphire could easily guide the unidirectional growth of MoS_(2) without the need for other specific synthetic conditions compared with c-plane and m-plane sapphire.The field-effect transistors(FETs)fabricated from the full-coverage films show an average and the highest mobilities of 28.5 and around 45 cm^(2)·V−1·s^(-1),respectively.
基金
This work was granted by the National Key Research and Development Program of the of China(No.2022YFA1203801)
the National Natural Science Foundation of China(Nos.51991340,51991343,52221001,52102168,and 52372145)
Hunan Key Research and Development Program Project(No.2022GK2005)
the Natural Science Foundation of Hunan Province(No.2023JJ20009)
the Hunan Province“Huxiang Talents”Project(No.2023RC3092)
the Natural Science Foundation of Chongqing,China(No.cstc2021jcyj-msxmX0321)
the Doctoral Scientific Research Foundation of Hubei University of Automotive Technology(No.BK202486).
作者简介
Rong Song,contributed equally to this work;Dingyi Shen,contributed equally to this work;Address correspondence:Jia Li,jiali2@hnu.edu.cn;Address correspondence:Xidong Duan,xidongduan@hnu.edu.cn。
