This work reports on the main competing processes and their contribution to the properties of SiO2 layers on polymers in large area AP‐PE‐CVD from ArN2O2‐HMDSO mixtures. The detailed space resolved surface analysis on the statically deposited films showed smooth SiOx films in the vicinity of the gas injection, as deposited by HMDSO radicals. At the gas effluent, due to HMDSO depletion, non‐depositing species interact with the polymer and induce rough deposits with high carbon content. The competition of plasma–polymer surface interaction with HMDSO radicals deposition, is further confirmed from the analysis of films grown on polymers with a “protecting” layer and with reverse gas flow direction. Under web roll conditions, HMDSO radicals deposition is dominant, resulting in high quality SiOx layers along the whole electrode length.

Pathways of formation and temporal evolution of the diffuse dielectric barrier discharge at atmospheric pressure were experimentally studied in this work by means of optical (fast imaging camera) and electrical diagnostics. The chosen model system is relevant for applications of plasma-enhanced chemical vapor deposition of thin silica-like film on the polymeric substrate, from cost-efficient gas mixtures of Ar/N 2 /O 2 /hexamethyldisiloxane. It was found that the discharge can gradually experience the phases of homogeneous low current Townsend-like mode, local Townsend to glow transition and expanding high current density (∼0.7 A cm −2 ) glow-like mode. While the glow-like current spot occupies momentarily only a small part of the electrode area, its expanding behavior provides uniform treatment of the whole substrate surface. Alternatively, it was observed that a visually uniform discharge can be formed by the numerous microdischarges overlapping over the large electrode area.

Vanadium oxide (VO2) thin films were prepared by atomic layer deposition using TEMAV (tetrakis[ethylmethylamido]vanadium) precursor and ozone as the reactant gas. Study on the precursor as well as oxidizer doses and temperature dependence showed none of them exhibited the characteristics of ideal ALD. The VO2 phase formation pathways, its process window, and surface roughness are found to be sensitive to the anneal conditions applied and the substrate used. The VO2 morphology on Al2O3 was found to be island-like whereas on Si/SiO2 either a nano particle formation or a continuous film was obtained. GIXRD demonstrated the VO2 crystallization window to be very narrow on Al2O3 and thick SiO2 while a relatively broad window is obtained on 1 nm SiO2. A reversible change in sheet resistance was measured with more than three orders of magnitude for a 30 nm film.

The diffuse dielectric barrier discharge in atmospheric pressure air was applied for the thin film deposition on polymeric web in industrially relevant roll-to-roll configuration. The silica-like film deposition was performed using the admixture of hexamethyldisiloxane precursor to air flow. Fast discharge imaging at 2 μs exposure time confirms plasma uniformity in a single current pulse time scale. Morphology and composition analyses indicate that the process results in ultrasmooth films (roughness comparable to initial substrate roughness) and shows the possibility to synthesize carbon-free layers.