The effect of obtaining conditions on the structure and composition of Cu-MoS2 coatings upon magnetron sputtering of composite targets

The surface morphology and phase composition of the coatings obtained by magnetron sputtering of Cu-MoS2 composite targets have been studied by X-ray diffraction, scanning electron microscopy and X-ray spectral microanalysis. X-ray diffraction studies of coatings show presence of two crystalline phases, namely Cu with face-centered cubic lattice and CuMo6S8 with a rhombohedral lattice. Studies of the surface morphology in Cu-CuMo6S8 coatings revealed two types of structures. One of the structures is realized in the form of globular formations, while the second is similar to the structure that had single-component Cu coating. X-ray spectral microanalysis showed that globular formations have higher Mo and S contents in comparison with other type of surface structure. The ratio between these elements is close to that in CuMo6S8. However, the Cu content is many times higher than the calculated amount for this compound. This suggests that globular formations are heterostructural where only one of the phases is CuMo6S8. Other possible phases in globular formations should be based on copper. The total area of globular formations in the coating increases with an increase in the proportion of MoS2 in the composition of the Cu-MoS2 sputtered composite target and strongly depends on the substrate potential.