Chapter 2: Controlled Growth of WS 2 Quantum dots by liquid exfoliation and Monolayer
2.5. Conclusion
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optimum growth. Finally, we have shown a simple salt-assisted approach to growing high- quality, large-area continuous monolayer WS2 film on different substrates by CVD. The influence of the change in the growth temperature (800-940 °C) was investigated to understand the effect on WS2 growth. We have systematically studied the Raman and PL properties of the as-grown WS2 on different substrates. We have briefly addressed the substrate-dependent built- in strain and doping effects. Thus, it is found that the growth substrates significantly affect the PL emission characteristics of the 1L-WS2. Our results indicate that the large-area monolayer WS2 grown on sapphire substrate contains fewer defects than that of the other substrates. The controlled synthesis procedures of these WS2 QDs and monolayer films could further open avenues for investigations into the fundamentals of light-matter interactions in these 2D systems and thus, pave way for the development of various optoelectronic devices.
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