Atomic force microscopic investigations of MoS₂ thin films produced by low pressure sulfurization

Molybdenum disulfide (MoS₂) thin films were produced on Si/SiO₂ substrate by low pressure sulfurization of molybdenum (Mo) film. Mo films are treated with sulfur vapor at different temperatures to investigate the effect of growth temperature on the structural and morphological features of MoS₂ films. Raman measurements confirmed the existence of multilayer MoS₂. Atomic force microscopy (AFM) measures film thickness and examines surface topography. The statistical analysis of variance (ANOVA) technique is applied to assess temperature effects and validate AFM findings. The growth temperature affects film thickness, surface roughness and grain size. Thickness increases with an increase in temperature while the roughness decreases. The least roughness is obtained when MoS₂ is produced at 800 °C. Interestingly, the grain size initially increases with increasing temperature and then drops. The largest grain size is found for sulfurization at 750 °C. These findings will help adjust MoS₂ thin film morphology and crystalline quality.