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Results of studies of the effect of the discharge current on the crystalline structure, surface morphology, and thickness of thin AlN coatings deposited by reactive dual magnetron sputtering on c-axis oriented sapphire wafers have been described. Using grazing incidence X-ray diffraction, it has been determined that the coatings have a wurtzite crystalline structure and at least two types of grains with different orientations of the (002) planes. Electron microscopy has revealed that the coatings are composed of vertically aligned columnar grains and a nucleation layer. The grains are uniformly distributed over the substrate surface; each of the grains consists of smaller crystallites. It has been found that the discharge current largely affects the concentration of grains of different orientations and has hardly any effect on the size of the nuclei.

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A metal–ceramic composite target for magnetron sputtering was fabricated for the first time by a robotic complex for the detonation spraying of coatings equipped with a multi-chamber detonation accelerator. A mixture of metal and ceramic NiCr/B4C powders was sprayed onto the copper base of the cylindrical composite target cathode. The study of the structure of a metal–ceramic composite coating target using scanning electron microscopy showed that the coating material is dense without visible pores; the elemental composition is evenly distributed in the material. The study of the cathode sputtering area after deposition in the DC mode showed that there are uniform traces of annular erosion on the target surface. The obtained cathode target with an NiCr-70B4C coating was used to deposit the NiB-Cr7C3 coating on flat specimens of 65G steel using equipment for magnetron sputtering UNICOAT 200. The coating was applied in the Direct Current mode. A dense NiB-Cr7C3 coating with a thickness of 2 μm was obtained. The NiB-Cr7C3 coating has a quasi-amorphous structure. The microstructures and concentration of oxygen and carbon impurities throughout the entire thickness of the coating were investigated by means of transmission electron microscopy. The results of the study show that the coatings have a nanocrystalline multi-phase structure. The microhardness of the NiB-Cr7C3 coating reached 10 GPa, and the adhesion fracture load exceeded 16 N. The results will open up new prospects for the further elaboration of technology for obtaining original composite cathodes for magnetron sputtering using detonation spraying of coatings.