Spectroscopic ellipsometry (SE) characterization of layered transition metal dichalcogenide
(TMD) thin films grown by vapor phase sulfurization is reported. By developing an optical
dispersion model, the extinction coefficient and refractive index, as well as the thickness of
molybdenum disulfide (MoS 2) films, were extracted. In addition, the optical band gap was
obtained from SE and showed a clear dependence on the MoS 2 film thickness, with thinner
films having a larger band gap energy. These results are consistent with theory and …