abstract
Molybdenum disulfide (MoS2) is a transition metal dichalcogenide, which along with graphene, has a great potential to become a material of choice for the next generation of nanoelectronics. We report the synthesis of a large-area MoS2 obtained by sulfurization of MoO3 using chemical vapor deposition (CVD) at different Ar base pressures. The optimal pressure for the growth was found to be similar to 50 mbar (millibar). The evolution of MoS2 phase as a function of Ar gas pressure was monitored by confocal Raman spectroscopy. As synthesized MoS2 shows direct bandgap of 1.6 eV evaluated by UV-vis spectroscopy. We report for the first time the valence band spectra and the work function of MoS2 on SiO2/Si calculated by ultraviolet photoemission spectroscopy, which was found to be 4.67 eV. In-situ electrical measurements demonstrated expected semiconducting behavior of the grown triangular crystals. These studies show MoS2 crystallites growth by controlling the parameters in CVD process.
keywords
TRANSITION-METAL DICHALCOGENIDES; CHEMICAL-VAPOR-DEPOSITION; SINGLE-LAYER MOS2; MOLYBDENUM-DISULFIDE; MONOLAYER MOS2; ATOMIC LAYERS; THIN-LAYERS; RAMAN-SCATTERING; PHASE GROWTH; GRAPHENE
subject category
Materials Science
authors
Sharma, DK; Ramana, EV; Fateixa, S; Hortiguela, MJ; Otero-Irurueta, G; Nogueira, HIS; Kholkin, A
our authors
Andrei Kholkin
Principal Researcher
Dhananjay K. Sharma
Post-Doc Fellowship
Helena Isabel Seguro Nogueira
Assistant Professor with Aggregation
Sara Fateixa
Junior ResearcherGroups
G1 - Porous Materials and Nanosystems
G2 - Photonic, Electronic and Magnetic Materials
G3 - Electrochemical Materials, Interfaces and Coatings
acknowledgements
DKS thanks Svaagata Erasmus Mundus for financial support for via Ph.D. fellowship. EVR acknowledges the financial support from Fundacao para a Ciencia e Tecnologia (FCT), Portugal (SFRH/BPD/75582/2010). SF thanks FCT for the Grant SFRH/BPD/93547/2013. MJH acknowledges UID/EMS/00481/2013 project. G O-I thanks FCT for his investigator grant (IF/01054/2015). The work was developed within the scope of the project CICECO-Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT Ref. UID/CTM/50011/2013), financed by national funds through the FCT/MEC and, when appropriate, co-funded by FEDER under the PT2020 Partnership Agreement.