Spectroscopic ellipsometry of large area monolayer WS2 and WSe2 films

In the present study, we report on dispersion function over a spectral range of 300 – 1700 nm (i.e. 0.73 – 4.13eV) for CVD-grown full area coverage monolayer WS2 and WSe2 films on SiO2/Si substrates. The result is obtained via the analysis of spectroscopic ellipsometry spectra by virtue of Tauc-Lorentz oscillators, which takes into account that absorption of these materials are attributed to the formation of the excitons.