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Title: CVD Growth of Monolayer MoS2 on Sapphire Substrates by using MoO3 Thin Films as a Precursor for Co-Evaporation
ABSTRACT Scalable synthesis of two-dimensional molybdenum disulfide (MoS 2 ) via chemical vapor deposition (CVD) is of considerable interests for many applications in electronics and optoelectronics. Here, we investigate the CVD growth of MoS 2 single crystals on sapphire substrates by using thermally evaporated molybdenum trioxide (MoO 3 ) thin films as molybdenum (Mo) source instead of conventionally used MoO 3 powder for co-evaporation synthesis. The MoO 3 thin film source provides uniform Mo vapor pressure in the growth chamber resulting in clean and reproducible MoS 2 triangles without any oxide or oxysulfide species. Scanning electron microscopy, Raman spectroscopy, photoluminescence spectroscopy and atomic force microscopy characterization were performed to characterize the growth results. Very high photoluminescence (PL) response was observed at 1.85 eV which is a good implication of high optical quality of these crystals directly grown on sapphire substrate.  more » « less
Award ID(s):
1728309
PAR ID:
10107189
Author(s) / Creator(s):
;
Date Published:
Journal Name:
MRS Advances
Volume:
4
Issue:
10
ISSN:
2059-8521
Page Range / eLocation ID:
587 to 592
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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