Layer-by-layer epitaxy growth of thickness-controllable two-dimensional tungsten disulfide  

作　　者：Jieyuan LIANG Zixing ZOU Junwu LIANG Di WANG Biao WANG Anshi CHU Jiali YI Cheng ZHANG Lizhen FANG Tian ZHANG Huawei LIU Xiaoli ZHU Dong LI Anlian PAN 

机构地区：[1]Key Laboratory for Micro-Nano Physics and Technology of Hunan Province,State Key Laboratory of Chemo/Biosensing and Chemometrics,Hunan Institute of Optoelectronic Integration,College of Materials Science and Engineering,School of Physics and Electronics,Hunan University,Changsha 410082,China [2]School of Physics and Electronics,Hunan Normal University,Changsha 410081,China [3]School of Electronic Information and Electrical Engineering,Changsha University,Changsha 410022,China [4]School of Physics and Telecommunication Engineering,Yulin Normal University,Yulin 537000,China [5]Units Semiconductor Technology Co.,Ltd.,Nanjing 210000,China

出　　处：《Science China(Information Sciences)》2024年第5期298-306,共9页中国科学（信息科学）（英文版）

基　　金：supported by National Key R&D Program of China(Grant Nos.2022YFA1402501,2022YFA-1204300);National Natural Science Foundation of China(Grant Nos.52372146,62375081,U22A20138,51972105,5222100162090035);Key Program of Science and Technology Department of Hunan Province(Grant Nos.2019XK20012020XK2001);Science and Technology Innovation Program of Hunan Province(Grant No.2021RC3061);Natural Science Foundation of Hunan Province(Grant No.2021JJ20016);Natural Science Foundation of Tianjin(Grant No.20JCYBJC00390);Open Project Program of Key Laboratory of Nanodevices and Applications,Suzhou Institute of Nano-Tech and Nano-Bionics,Chinese Academy of Sciences(Grant No.22ZS01).

摘　　要：Bilayer transition metal dichalcogenides(TMDs)balance the high mobility of single layers with the high state density of multilayers and therefore have promising application prospects in high-performance electronics.However,the layer-controlled growth of 2D materials is still confronted with challenges such as poor repeatability between different labs and a limited understanding of the growth mechanism at the atomic scale.Herein,we report a new carbon-assisted chemical vapor deposition process that can realize the growth of WS_(2) sheets with high yield,precise thickness controllability,and repeatability.We show that carbon can act as a reducing agent and catalyst that preferentially reacts with the WO3 precursor to form intermediate WO3−x products with low-valence state W.The resulting oxycarbide gas has a low surface adsorption energy when deposited on the surface of as-grown WS_(2),which provides nucleation sites for the subsequent layer of WS_(2) growth and leads to the vertical growth of WS_(2) sheets.The growth mechanism is thoroughly investigated.Electrical transport measurements show that the produced bilayer WS_(2) possesses a high carrier mobility(up to 58 cm^(2)·V^(−1)·s^(−1))and small subthreshold swing(estimated to be 148 mV/decade),which are among the best reported results for TMDs produced using CVD.

关 键 词：WS2 thickness-controlled growth chemical vapor deposition ADDITIVE carbon 

分 类 号：TQ136.13[化学工程—无机化工]