Optical characterization of 2D heterostructure MoS2/WS2 using spectroscopic ellipsometry
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https://doi.org/10.54939/1859-1043.j.mst.101.2025.117-123Keywords:
Heterostructure MoS2/WS2; Spectroscopic ellipsometry; Tauc-Lorentz model; Optical properties.Abstract
TMDC materials like MoS2 and WS2 are well known for their unique monolayer properties, ideal for optoelectronic applications. Stacking these monolayers enhances the properties beneficial for light detection and harvesting devices. This study investigates the dielectric function and critical point (CP) energies of heterostructure MoS2/WS2 using spectroscopic ellipsometry (SE) within the spectral range of 1.5 to 6.0 eV at different angles. The SE method, employing the Tauc-Lorentz model for detailed analysis, confirms the formation of high-quality TMDC heterostructure and provides precise values for intrinsic properties. These results are crucial for optimizing TMDC-based optoelectronic devices for military and commercial applications.
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