Abstract
This article illustrates the problem ensuring homogeneity and uniformity of nanoscale coatings obtained in vacuum by carbon vapor deposition. Carbon vapors are obtained by heating in a vacuum with one or more electron beams from a water-cooled crucible, which is covered with a molten layer of refractory metal. Due to the peculiarities of the trajectory of the movement of carbon vapors from the crucible to the substrate, a situation may arise with the formation of a "visor" type defect on the coating, which prevents the uniformity of the coating.