Hybrid nanofilms (Ni@C) consisting of nickel particles encapsulated in a carbon shell are grown by the method of magnetron sputtering. Clustered nature of film formation is reached due to the specific conditions of deposition (low temperature, high pressure). Two groups of samples with different concentration ratios C:Ni are investigated. As determined, the clusters of the Ist group of samples (C:Ni = 60:40) are amorphous and form a crystal structure only at certain critical temperature, while the clusters of the IInd group (C:Ni = 30:70) form a crystal structure within the plasma. The nature of formation of nanocomposite films with different concentrations of carbon and substrate temperatures is considered.