Toward roll-to-roll deposition of high quality moisture barrier films on polymers by atomospheric pressure plasma assisted process

An atmospheric pressure dielectric barrier discharge (DBD) was applied for the deposition of silica-like moisture barrier films on polyethylene 2,6 naphthalate foil. The diffuse plasma was sustained between two cylindrical drum electrodes in N2/O2/Ar gas flow with the addition of tetraethyl orthosilicate. The chemical composition, morphology and water vapour transmission rate of the moisture permeation barrier layers were studied as a function of the dynamic deposition rate and substrate temperature. It was demonstrated that dense silica-like layers of 100¿nm thick with a good permeation barrier of ˜1.8¿×¿10-3¿g¿·¿m-2¿·¿day (at 40¿°C, 90% RH), corresponding to three orders of magnitude barrier improvement with respect to the pristine polymer, can be deposited in an atmospheric pressure process