Transformation of metal-oxide nanostructures in the process of afteroxidation of iron reactively evaporated in oxygen atmosphere

The methods of atomic force microscopy combined with the digital processing of images were used to study the change in the morphology of nanostructured metal-oxide coatings obtained by reactive evaporation at 10⁻⁶ torr in the atmosphere of oxygen and further low-temperature iron afteroxidation in an air atmosphere at different temperatures. It is shown that a nanostructured layer with a unimodal distribution according to the size and degree of nonsphericity of the particle is formed in the case of sputtering. Using the sample detection methods, it is shown that a unimodal distribution is transformed into a bimodal distribution at an increase in the reoxidation temperature from 50 to 200°C, after which it becomes a trimodal distribution, which proves that the building blocks of a nanostructured layer are nanoparticles and four- and 16-particle surface nanoparticle conglomerates. This structure can explain the functional properties of these coatings, which are of practical importance.