Surface Dynamics of SiO2 -like Films on Polymers Grown by DBD Assisted CVD at Atmospheric Pressure

The development of the morphology and surface roughness of amorphous SiO2-like films, on various polymeric substrates was analyzed by atomic force microscopy. The inorganic oxide films were deposited from organo-silicon precursors with different reactive gases using dielectric barrier discharge assisted chemical vapor deposition (DBD-CVD) at atmospheric pressure in a roll-to-roll configuration. Detailed study on the roughness statistical parameters characterizing morphology shows that DBD-CVD films grow in a conformal and layer-by-layer like fashion on polymers very similar to films produced by atomic layer deposition process. Independent of substrate (planarised and non-planarised polyethylene-2,6-napthalate) and methodology used to build the thickness as stacks or single layers, the films were found to be smooth, both locally and globally, and show negligible development of roughness with thickness (≤350 nm). The scaling exponents observed, show that the film growth does not fall into any of the universality classes that have been reported so far.