Characteristics of two-dimensional MoS2 films deposited using a reactive thermal evaporation method

Abstract

In this study, we fabricated three- and four-molecule-thick two-dimensional (2-D) MoS2 films using a reactive thermal evaporation method. The number of layers was estimated using optical transmittance. The MoS2 films had a 1.89-eV direct band gap and 1.42 approximate to 1.45-eV indirect band gap. The band-gap energy was estimated using the optical absorbance curves. The direct band gap transition dominated the MoS2 films. The number of molecular layers in the 2-D MoS2 films could be controlled relatively easily. The development of thin-film transistors using reactive thermally evaporated MoS2 active layers is currently underway.