An Auger Electron Spectroscopic Study of Ion and Plasma Etching of Thin Films Obtained by Plasma Activation of the Microdroplet Products of Thermal Degradation of Solid Polypropylene

The matrix properties of films obtained by plasma-enhanced deposition of the microdroplet products of thermal degradation of solid propylene (PEPP) were studied. The sample thickness was 120 nm, and the volume fraction of the dense phase was 10%. The rates of ion sputtering and the rates and some features of etching of the PEPP films at various plasma parameters were determined from the concentration profiles of the basic film-forming element (carbon) as obtained by Auger electron spectroscopy (AES) in combination with layer-by-layer sputtering by argon ions. It was shown that the films were highly uniform over the entire film depth down to the substrate. The oxygen concentration on the sample surface and over the film depth were determined after the plasma etching of the film in the residual air (the depth of penetration and formation of oxygen-containing groups did not exceed 30 nm). The alternation of interference colors on the PEPP surface observed in scattered light during the plasma etching was described. Comparison of the results obtained with the data for initial polypropylene made it possible to conclude that the matrix forming the basis of the PEPP coatings (90%) can be treated as a polymer-like structure.