Synthesis of MoS2 Thin Film

Tuesday, 7 October 2014: 16:40
Expo Center, 1st Floor, Universal 18 (Moon Palace Resort)
J. Mun (Sungkyunkwan University, Korea Research Institute of Standards and Science), D. Kim (Sungkyunkwan University), Y. Shin, J. Yun, S. Kang (Korea Research Institute of Standards and Science), and T. Kim (Sungkyunkwan University)
The two dimensional materials such as graphene, and thin films of transition metal dichalcogenides are became alternative and attracted for use in next generation nanoelectronic devices due to their planar nature and mechanical flexibility. Especially, graphene is promising and most widely studied two-dimensional material for use in flexible and transparent devices. Despite of all these excellent electrical properties, it is difficult to fabricate on/off and logic devices using grapheme because of zero band gap. In contrast, molybdenum disulfide (MoS2) has the band gap between 1.2 and 1.8 eV as a function of the number of layers (band gap of monolayer MoS2is 1.8eV) (K. F. Mak, et al., 2010).

Many researchers have been used various methods such as mechanical exfoliation (B. Radisavljevic, et al., 2011), sulfurization (Y. Zhan, et al., 2012), chemical vapor deposition (CVD)(Y. H. Lee, et al., 2012; Y. Shi, et al., 2012) to grow MoS2 thin film. In the case of mechanical exfoliation, excellent electrical properties were shown. However, there is limitation of mass production. CVD method is a typical method and there are many reports. However, the method for large area MoS2growth on dielectric substrate at the relatively low temperature is not reported.

In this work, we successfully have grown a few layer MoS2 thin film (Fig. 1) on a SiO2 substrate using molybdenum hexacarbonyl (Mo(CO)6) and hydrogen disulfide (H2S) by a CVD method. The large area MoS2 thin film was grown by optimization of the Mo and S precursor ratio and growth conditions such as process pressure and temperature. The properties of the films were analyzed using atomic force microscope (AFM), transmission electron microscope (TEM), and Raman spectroscopy.


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