Large-Area Deposition of MoS2by Pulsed Laser Deposition with In SituThickness Control

A scalable and catalyst-free method to deposit stoichiometric molybdenum disulfide (MoS2) films over large areas is reported, with the maximum area limited by the size of the substrate holder. The method allows deposition of MoS2layers on a wide range of substrates without any additional surface preparation, including single-crystal (sapphire and quartz), polycrystalline (HfO2), and amorphous (SiO2) substrates. The films are deposited using carefully designed MoS2targets fabricated with excess sulfur and variable MoS2and sulfur particle size. Uniform and layered MoS2films as thin as two monolayers, with an electrical resistivity of 1.54 × 104Ω cm–1, were achieved. The MoS2stoichiometry was confirmed by high-resolution Rutherford backscattering spectrometry. With the method reported here, in situgraded MoS2films ranging from ∼1 to 10 monolayers can be deposited.