Fabrication of MoS₂ thin film transistors via selective-area solution deposition methods

We report a simple and selective solution method to prepare Molybdenum Disulfide (MoS₂) thin films for functional thin film transistors (TFTs). The selective area solution-processed MoS₂ grows on top and around the gold (Au) source and drain electrodes and in the channel area of the TFT. MoS₂ thicknesses in the channel area are in the order of 11 nm. A mechanism for the selective growth is also proposed. The Au electrodes act not only as contact, but also as a catalytic surface for the hydrazine hydrate used in the reaction, which induces the selective growth of MoS₂ on the Au surface and into the channel region. This one step process demonstrates functional TFTs with a carrier mobility of ∼0.4 cm² V^-1 s^-1.