Toward epitaxially grown two-dimensional crystal hetero-structures: Single and double MoS2/graphene hetero-structures by chemical vapor depositions

• Published in: Applied physics letters Vol. 105; no. 7
• Main Authors: Lin, Meng-Yu, Chang, Chung-En, Wang, Cheng-Hung, Su, Chen-Fung, Chen, Chi, Lee, Si-Chen, Lin, Shih-Yen
• Format: Journal Article
• Language: English
• Published: Melville American Institute of Physics 18.08.2014
• Subjects: Applied physics; Chemical vapor deposition; Controllability; Cross-sections; Crystal growth; Crystal structure; Epitaxial growth; Graphene; Image transmission; Molybdenum disulfide; Organic chemistry; Sapphire; Semiconductor devices; Substrates; Transistors; Transmission electron microscopy
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/1.4893448

Uniform large-size MoS2/graphene hetero-structures fabricated directly on sapphire substrates are demonstrated with layer-number controllability by chemical vapor deposition (CVD). The cross-sectional high-resolution transmission electron microscopy (HRTEM) images provide the direct evidences of layer numbers of MoS2/graphene hetero-structures. Photo-excited electron induced Fermi level shift of the graphene channel are observed on the single MoS2/graphene hetero-structure transistors. Furthermore, double hetero-structures of graphene/MoS2/graphene are achieved by CVD fabrication of graphene layers on top of the MoS2, as confirmed by the cross-sectional HRTEM. These results have paved the possibility of epitaxially grown multi-hetero-structures for practical applications.