Electrical Properties of Structures Based on Two-Dimensional Molybdenum Disulfide

The electrical characteristics of molybdenum disulfide films synthesized by CVD from powder precursors MoO3 and S were studied. Silver contacts were used to measure the current–voltage characteristics of MoS2 films deposited on SiO2/Si substrates. The dependence of the properties of the Ag/MoS2 contact on the number of MoS2 film layers was discovered. For multilayer molybdenum disulfide films, an ohmic contact is formed between silver and MoS2, while for few-layer films, a Schottky barrier is formed. From the temperature dependences of the current–voltage characteristics, the activation energies of conductivity were calculated to be 0.26 and 0.22 eV for two-layer and three-layer MoS2 films, respectively. For single-layer MoS2 films, the current–voltage characteristics showed the presence of a resistive switching effect. Using the deep-level charge spectroscopy (Q-DLTS) method, a level of 0.20 eV below the conduction band was found in MoS2 films. Based on the vertical van der Waals heterostructure of graphene/MoS2/Si, a solar cell was created that can generate a voltage of 0.48 V when illuminated by a halogen lamp.