Hardness of Mn₂V₂O₇ thin films and its influential factors

Mn₂V₂O₇ thin films were deposited onto amorphous glass substrates using a chemical bath deposition method and different deposition time. X-ray diffraction (XRD) analysis was used to define the structure of the films. Their roughness, thickness, and surface properties were evaluated through atomic force microscopy (AFM). The hardness of the films was measured using a nanohardness tester. The film thickness, average grain size, and roughness were positively correlated with each other. These three parameters were observed to increase with the deposition time. The film thickness and average grain size were inversely correlated with the hardness and roughness. In addition, the number of crystallites per unit area and the dislocation density were observed to be positively correlated with the hardness and roughness. This study was designed to elucidate and formalize the underlying reasons for these relationships.