Physics-based modelling of MoS₂: The layered structure concept

Recently, continuum-based technology computer aided design (TCAD) device models have been used to investigate the advantages and limitations of transition metal dichalcogenides (TMDs), as one of the promising families of 2D semicoductors. Nevertheless, a complete physics-based model is still missing. In this work, TCAD methodology is advanced for MoS₂ devices, as the material system is modelled considering a structure formed by layers of MoS₂ and Van-der Waals gaps, as opposed to a continuous semiconductor, The structure is benchmarked against previous experimental data and the behavior of thin and multilayer MoS₂ is studied. Then, the model is used to evaluate the electron distribution and current density in a MoS₂-based field effect transistor (FET). The analysis of the layered-structure provides additional understanding of the electrostatics and carrier transport in 2D semiconductors.