Interface analysis of oxide free MoS₂ films fabricated by solution process

We report a solution-based approach for the synthesis of oxidation-free MoS₂ films, focusing on interface analysis. Through a sulfurization-free solution process and single-step annealing, the oxidation-free MoS₂ film is successfully prepared on Si₃N₄ surfaces, showing improved uniformity with a surface roughness below 0.5 nm and a thickness of 4 nm at a precursor solution concentration of 30 mM, annealed between 700 and 800ºC. The MoS₂ films exhibit a hexagonal lattice structure with crystallographic orientations of (1 1 0 0) and (1 2 1 0) with lattice spacings of 0.27 nm and 0.16 nm respectively. Interfacial analysis by X-ray photoelectron spectroscopy (XPS) on SiO₂ reveals migration of oxygen species as evidenced by a shift in the Si 2p spectrum at binding energies between 102.6 eV and 102.8 eV. MoS₂ films on Si₃N₄ show a complex Si 2p peak evolution at binding energies between 100.9 and 101.8 eV, providing valuable insights into the synthesis of oxide-free MoS₂ films for potential applications in advanced electronic devices.